El e c t r o n i c Ex h i b i t s

Ro o m 312, Le v e l 3

Hours:

Sunday, April 26: ...... 1:00 pm - 7:00 pm

Monday-Wednesday, April 27-29: ...... 7:00. am - 10:00 pm

Thursday, April 30: ...... 7:00. am - 4:15 pm

Exhibit Topics:

Breast Imaging...... pages 175-185

Cardiopulmonary Imaging ...... pages 185-207

Efficacy, Education, Administration and PACS...... pages 207-213

General and Emergency ...... pages 213-222

Gastrointestinal/Liver/Biliary/Pancreas Imaging...... pages 223-258

Genitourinary/OB/GYN Imaging...... pages 259-275

Musculoskeletal Imaging...... pages 275-309

Neuroradiology/Head and Neck ...... pages 309-332

Nuclear Medicine/...... pages 333-339

Pediatric Imaging...... pages 339-344

Vascular and Interventional Radiology...... pages 345-356

173

El e c t r o n i c Ex h i b i t s :

E002. Nonincidental and Incidental Disorders of the Breast: Br e a s t CT Diagnosis Katz, D.1; Rausch, D.2; Ring, B.3; Levin, G.4; Bergstrom, R.5; E001. 64-Slice MDCT and 3D Image Postprocessing to Depict Kranz, A.1; Fuchs, S.1 1. Winthrop-University Hospital, Mineola, Deep Inferior Epigastric Artery Perforators for the NY; 2. Mount Sinai Medical Center, New York, NY; 3. Memorial Preoperative Planning of Breast Reconstructive Sloan Kettering Center, New York, NY; 4. Beth Israel (CME Credit Available) Medical Center, New York, NY; 5. Palo Alto Medical Foundation, Mitsumori, L.; Warren, B.; Dighe, M.; Kolokythas, O.; Cuevas, Palo Alto, CA C.; Shuman, W.; Dubinsky, T. University of Washington, Seattle, WA Address correspondence to D. Katz ([email protected]) Address correspondence to L. Mitsumori ([email protected]. edu) Background Information: The purpose of this exhibit is to review our experience with the identification of nonincidental Background Information: Recently, MDCT has and incidental breast pathology at several institutions over the been applied for the preoperative planning of abdominal perfora- past decade, on CT examinations of the chest and/or abdomen . tor flap surgery . The newer generations of CT platforms that can achieve near-isotropic voxel acquisitions Educational Goals/Teaching Points: We have diagnosed a now permit the use of numerous 3D image postprocessing tech- wide variety of benign and to a much lesser extent malignant niques to these data sets to best define the number and distribu- incidental breast pathology on CT of the abdomen and/or tion of rectus perforating arteries . This information facilitates the chest . Representative examples of incidental and non-incidental selection and resection of the best rectus flap, thereby reducing breast pathology will be shown, including calcifications, , operative time (average saving 100 minutes), and decreasing masses, , asymmetric tissue, infection, implants, postsurgical complications . The purpose of this abstract is to trauma, lesions, and postsurgical/postradiation describe our MDCT protocol for a 64-slice scanner; and illus- change . Regionally advanced will also be trate the use of different 3D image postprocessing techniques to shown . Selected cases of PET-CT will also be demonstrated depict the small perforating vessels for the surgeon . where incidental or nonincidental breast pathology was identi- fied . Educational Goals/Teaching Points: All exams are done on a 64-slice scanner . Images are acquired from 4 cm above the Key Anatomic/Physiologic Issues and Imaging Findings/ umbilicus to the lesser trochanters of the femurs . Studies are Techniques: CT cases will be demonstrated, along with mammo- acquired at 120 kVp, with auto-smart mA . Image timing is graphic correlation if appropriate . The relevant literature will be achieved with a timing bolus monitored in the right external iliac briefly reviewed . Similarly, selected examples of incidental and artery . Scan acquisition at timing bolus peak + 10 seconds . The non-incidental breast pathology as demonstrated on PET-CT will 0 .625 mm axial images are sent to an independent 3D worksta- also be shown, with a brief review of the literature . The approach tion and a second axial image set is reconstructed at 2 5. mm for to incidental breast pathology on CT will also be reviewed . viewing the abdominal/pelvic viscera and bones . For these exams, a postprocessing protocol was defined that consists of: Conclusion: A wide variety of disorders of the breast may be axial and sagittal oblique maximum intensity projection recon- identified on CT of the chest and/or abdomen, whether inten- struction (MIP) images to define the course and measure the tionally or not, especially with MDCT and thin sections used for size of the proximal superficial inferior epigastric arteries; axial routine imaging . Such findings can be missed if the radiologist and sagittal oblique MIP images of the three dominant deep does not include the in her/his search pattern . We have inferior epigastric rectus perforating (DIEP) arteries on the right seen numerous such cases and call this to the attention of all and then left sides, and a volume rendered view of the skin sur- radiologists interpreting body CT examinations . Less commonly, face of the anterior abdominal wall to depict the location of the CT may be specifically performed for breast evaluation . Similarly, origins of each DIEP arteries in relation to the umbilicus . such findings may also be seen on PET-CT examinations per- formed intentionally for staging breast cancer or for other rea- Key Anatomic/Physiologic Issues and Imaging Findings/ sons . Techniques: A 64-slice MDCT protocol is used to generate near- isotropic imaging data sets to allow 3D image postprocessing . Image postprocessing permits creation of volume rendered, mul- E003. Radiologic, Cytologic and Histologic Correlation of tiplanar reformations, and MIP reconstructions to depict the vari- -Guided Fine Needle Aspiration Biopsies of the ability in the size, number and distribution of DIEP arteries . Breast: Analysis of Discordant Cases (CME Credit Available) Durand, A.1; Flowers, C.1; Ljung, B.1; Jensen, K.2; Wolverton, D.1; Conclusion: Near-isotropic MDCT data sets are used with 3D Brenner, R.2 1. University of California, San Francisco, San image postprocessing to create rendered images of the small Francisco, CA; 2. No Institutional Affiliation abdominal perforating arteries . This preoperative imaging short- Address correspondence to A. Durand ([email protected]) ens the operative time and reduces the number of complications of this type of breast reconstructive surgery . Objective: Increased use of mammographic screening has result- ed in improved detection of nonpalpable breast lesions, many of which are initially sampled under ultrasound guidance . Using cytological analysis, imaging and clinical findings (the “triple test”), accurate diagnoses can be made provided concordance is present between the diagnostic modalities . The purpose of this study was to examine concordance rates between ultrasound classification, cytologic rapid review, cytologic final diagnosis and 175 El e c t r o n i c Ex h i b i t s : Breast histologic diagnosis on ultrasound-guided fine needle aspiration mation slightly increased using stereotactic guidance with an (US FNA) from a large cancer center with on-site cytology sup- automated 14 gauge needle compared with an 11 gauge vacu- port, and to critically review all discordant cases . um-assisted device [18/74 (24%), vs . 1/7 (14%), p=0 .86] and when =<6 samples were obtained compared with >6 samples Materials and Methods: Consecutive US FNAs with histologic [24/85 (28%) vs . 6/29 (21%), p=0 43]. . The likelihood of DCIS follow-up from January, 1999 to June, 2006 were identified from underestimation markedly increased using ultrasound guidance the radiology procedure log and the pathology database at the with an automated 14 gauge needle, however there was no dif- University of California-San Francisco (UCSF) Comprehensive ference between lesions yielding DCIS (11/27, 41%) vs . DCIS Cancer Center (total of 298 cases) . Imaging and pathology with “possible invasion” (4/10, 40%) . Among the 114 lesions reports were reviewed, summarized and entered into a database that yielded pure DCIS, 49 (37%) yielded high grade DCIS, 50 for analysis . FNA and histologic slide material was examined (38%) yielded intermediate grade DCIS, 12 (9%) yielded low when necessary, and for all discordant cases . grade DCIS and in three (2%) lesions DCIS grading was not known . Underestimation occurred in 37% (18/49) for high grade Results: Concordance rates for rapid review (on-site immediate DCIS, 22% (11/50) for intermediate grade DCIS and 25% (3/12) evaluation) to final cytologic diagnosis and for cytologic to histo- for low grade DCIS . logic diagnosis were very high (90% or greater) Concordance. rates between ultrasound impression and cytologic diagnosis Conclusion: DCIS with “possible invasion” at percutaneous were highest for atypical and malignant lesions . is a stronger predictor of invasive disease at surgery than the diagnosis of DCIS only . Given the higher risk of underes- Conclusion: Ultrasound-guided fine needle aspirations with on-site timation a sentinel node biopsy should be considered in this immediate cytologic evaluation show high concordance rates subset of patients . between cytologic and histologic diagnoses . With expert on-site immediate cytologic evaluation, initially non-diagnostic or discord- ant cases can be converted to core biopsy during the same proce- E005. Imaging Evaluation of Breast Implants: Complications dure (22% of cases in this series) to avoid a delay in diagnosis . Use and Implant-Associated Pathology (CME Credit Available) of the “triple test” algorithm allows for accurate, rapid diagnosis . Tyler, E.; March, D.; Hansen, A.; Miller, V. Baystate Medical Center, Springfield, MA Address correspondence to E. Tyler ([email protected]) E004. Underestimation of Ductal – Is “Possible Invasion” More Predictive of Invasive Carcinoma Background Information: Breast augmentation has been in Than Pure Ductal Carcinoma In Situ? practice since the late 19th century . The first such procedure in Arazi-Kleinman, T.1,2; Causer, P.2; Nofech Mozes, S.2; Jong, R.2 1. 1895 involved the autologous transplant of a lipoma . Subsequent Sourasky Medical Center, Tel Aviv, Israel; 2. Sunnybrook Health techniques have included free injection of paraffin and silicone . Science Centre, Toronto, Canada Silicone gel implants were first used in 1962 . Since then, an esti- Address correspondence to T. Arazi-Kleinman (t_arazikleinman@ mated 1-2 million women have undergone silicone breast aug- yahoo.com) mentation both for cosmesis and for reconstruction following . Saline implants gained popularity in 1992 when the Objective: The objective was to compare the likelihood of FDA temporarily restricted the use of silicone implants . Patients underestimation of ductal carcinoma in situ (DCIS) vs . DCIS with with implants can provide a challenge in screening and diagnos- “possible invasion” at percutaneous breast biopsy . tic due to implant related complications as well as unrelated, concomitant . Implant complications Materials and Methods: Of 3,836 consecutive lesions that include rupture, capsular contracture, and herniation through the underwent percutaneous biopsy, 132 lesions revealed DCIS with- fibrous capsule, migration, and peri-implant fluid collections . In out frank invasion . Subsequent resection pathology results were addition, implants may be affected by benign and malignant neo- retrospectively compared with needle biopsy results according to plasms . Hematologic and inflammatory conditions may also a diagnosis of DCIS or DCIS with “possible invasion” on needle involve breast implants and affect their imaging appearance . biopsy and presence of invasive carcinoma on resection patholo- gy . Fisher’s exact test was used to determine differences between Educational Goals/Teaching Points: The goals are to review the groups . the imaging appearance of different types of implants and their potential complications; review the imaging appearance of other Results: Of 132 lesions, 114 were DCIS vs . 18 DCIS with “possi- pathologic entities that may affect breast implants; and describe ble invasion” at percutaneous biopsy . Thirty-nine of 132 lesions how the use of different imaging modalities may narrow the dif- (29 .5%) revealed invasive cancer at subsequent resection pathol- ferential diagnosis of implant-related breast pathology and con- ogy [32/114 (28%) DCIS and 7/18 (39%) DCIS with possible tribute to patient management . invasion, p=0 .5] . The likelihood of underestimation was higher when DCIS with possible invasion was diagnosed compared with Key Anatomic/Physiologic Issues and Imaging Findings/ DCIS when stereotactic biopsy using an automated 14 gauge Techniques: Imaging modalities will include , needle was performed [3/6 (50%) vs . 18/74 (24%), p=0 .37] and sonography, and MRI . The different types of implants will be dis- when <=6 samples were obtained [7/15 (47%) vs . 26/85 (31%), cussed and examples provided . The imaging findings of intra- p=0 .26] . The likelihood of underestimation was also higher in and extracapsular implant rupture and other complications, along clinically vs . screen detected lesions [3/6 (50%) vs . 5/14 (35%) with potential diagnostic pitfalls will be reviewed . Pathologic enti- respectively, p=0 55]. for lesions yielding DCIS with “possible ties that can affect breast implants, other than those related to invasion” on biopsy pathology . The likelihood of DCIS underesti- implant complications, will also be reviewed and discussed .

176 El e c t r o n i c Ex h i b i t s : Breast

Examples will be provided of both benign and malignant breast artifact is of little consequence or representative of a major prob- lesions . Strategies for imaging these patients will be provided . lem that may require input from service and/or engineering staff .

Conclusion: Familiarity with the imaging appearance of breast Key Anatomic/Physiologic Issues and Imaging Findings/ implants, their associated complications, and the appearance of Techniques: In this exhibit, artifacts will be classified as due to concurrent breast disease are important elements of breast imag- patient factors, gantry factors, and/or detector factors, including ing, and will aid in accurate diagnosis . lag, ghosting, pixel drop out, excessive noise, and gray scale inversion . Examples of common artifacts will be presented along with descriptions of the artifacts, their causes, and their remedies . E006. Spectrum of Disease in the Male Breast (CME Credit Available) Conclusion: Artifacts identified on selenium-based digital mam- Iuanow, E.1; Fein-Zachary, V.1; Mehta, T.1; Kettler, M.2; Slanetz, mography may be due to patient factors, gantry factors, and/or P.1 1. Beth Israel Deaconess Medical Center, Boston, MA; 2. detector factors . Understanding artifacts is an important compo- Oregon Health and Science University, Portland, OR nent of maintaining high image quality . Address correspondence to P. Slanetz ([email protected])

Background Information: Although pathology within the male E008. Relationship Between the Age, Breast Density on breast is less commonly encountered compared to the female Digital Mammography and the Risk of Breast Cancer and breast, an understanding of various conditions affecting the male Benign Lesions in Chinese Women breast remains essential to the practice of breast imaging . Using Du, T.; Wang, Y.; Zhang, C.; Yu, S.; Yan, Y.; Wang, X.; Zhang, W.; mammography, ultrasound, and/or magnetic resonance imaging, Zhang, Y. Fuxing Hospital Affiliated to Capital University of the imaging findings of various diseases and conditions affecting Medical Sciences, Beijing, China the male breast will be reviewed . These conditions will include Address correspondence to T. Du ([email protected]) breast cancer, gynecomastia, epidermoid inclusion cysts, meta- static disease, and other rare benign tumors such as glomus Objective: The purpose of this study was to establish whether a tumors, inflammatory pseudotumor, and rhabdomyosarcoma . correlation exists between the factors including age, the percent- The pathophysiology and management of these conditions will age of mammographic density and the risk of breast and also be discussed . benign lesions in Chinese women .

Educational Goals/Teaching Points: The purpose of this exhibit Materials and Methods: The mammographic images of 1,621 is to review the anatomy of the male breast; and describe imag- subjects were independently interpreted by two experienced ing findings of a variety of diseases that affect the male breast . radiologists . Sixty-two patients with breast cancer among the total group were proved by surgical histopathology and 192 Key Anatomic/Physiologic Issues and Imaging Findings/ cases with benign breast lesion have the evidence of pathology Techniques: This exhibit will review mammographic, ultrasono- or other imaging methods including MR and ultrasound (US) . graphic, and MRI of male breast disease and correlate it with According to their age, all subjects were divided into five groups, pathophysiology . including <30, 31-40, 41-50, 51-60 and >61 years . All mammo- grams were measured using the semiquantitative planimetry by Conclusion: Radiologists will better understand the imaging find- drawing regions of interest to obtain the percentage of fibroglan- ings and the underlying pathophysiology of various diseases and dular tissue occupying the total area of the breast . According to conditions affecting the male breast . the percentage of mammographic density, they were divided into four groups, including <25%, 25-50%, 51-75% and >75% .

E007. Digital Mammography Artifacts: What the Radiologist Results: A statistically significant difference was seen in mammo- Needs to Know (CME Credit Available) graphic density among various age groups . Mammographic den- Geiser, W.; Stephens, T.; Santiago, L.; Haygood, T.; Whitman, G. sity decreased with increasing age . The difference of breast densi- The University of Texas M. D. Anderson Cancer Center, Houston, TX ty between the two groups of 41-50 years and 51-60 years was Address correspondence to G. Whitman (gwhitman@mdander- most significant (Z=-11 7,. p<0 .001) . The detection rate of 62 son.org) breast cancers in the five age groups from youngest to oldest was 2 1%,. 1 1%,. 3 .3%, 4 .3% and 10 9%,. respectively . In 62 Background Information: The purpose of this educational breast cancers the proportion of patients in four mammographic exhibit is to demonstrate common artifacts encountered in sele- density groups from low to high density was 17 7%,. 16 1%,. 21% nium-based digital mammography . As the number of digital and 45 .2% respectively . Multinomial logistic regressive analysis mammography units continues to increase, it is important that displayed that the detection rate of breast cancer trends increase radiologists be able to recognize common artifacts and under- with age (Wald chi-square value=40 9,. p<0 .001) and breast den- stand the causes of the artifacts . sity (Wald chi-square value=17 6,. p<0 001). . The detection rate of breast cancer was three times more in the older age group com- Educational Goals/Teaching Points: The educational goals of pared with the younger age group (OR value=3) and 1 9. times this exhibit are to categorize digital mammographic artifacts as more in the higher breast density group compared with the patient-related, gantry-related, and/or detector-related . The radi- lower density group (OR value=1 9). . The detection rate of breast ologist should become familiar with the causes of common digit- benign lesions increased with increasing age, but the mammo- al mammography artifacts . In addition, the radiologist should graphic density had no correlation with the detection rate of gain familiarity in troubleshooting and understand whether the benign breast lesions .

177 El e c t r o n i c Ex h i b i t s : Breast

Conclusion: Age and mammographic density are important risk E010. Percutaneously Diagnosed Benign Papillary Lesions of factors of breast cancer in Chinese women . The effect of age on the Breast: Pathological Upgrade Frequency at Subsequent risk of breast cancer is more significant than that of breast densi- Surgical Excision (CME Credit Available) ty . The relationship between the mammographic density and the Chetlen, A.; Schetter, S.; Van Hook, D.; Han, B. Penn State Milton risk of breast cancer is more predominant in postmenopausal S. Hershey Medical Center, Hershey, PA older women . Address correspondence to A. Chetlen ([email protected])

Objective: The purpose of this research was to evaluate the E009. Does Isolated Flat Epithelial Atypia on Vacuum- pathologic upgrade frequency of benign papillary lesions of the Assisted Breast Core Biopsy Require Surgical Excision? breast discovered on stereotactic or ultrasound-guided core biop- (CME Credit Available) sy that proceeded to excisional biopsy and to evaluate the clini- Dialani, V.; Venkataraman, S.; Fein-Zachary, V.; Littlehale, cal stability of nonexcised lesions with long-term radiological fol- N.; Mehta, T. Beth Israel Deaconess Hospital, Brookline, MA low-up . Address correspondence to V. Dialani ([email protected]. edu) Materials and Methods: A retrospective review was undertaken of 37 ultrasound-guided large core breast biopsies or stereotactic Objective: The objective was to determine if surgical excision is core breast biopsies performed in the last nine years (September, warranted when flat epithelial atypia is diagnosed in isolation of 1999-September, 2008) at our institution which yielded a diag- other atypia on breast core biopsy . nosis of intraductal papilloma or papillomatosis . Surgical patho- logic follow-up was available in 28 cases and at least 24 months Materials and Methods: Using an IRB approved protocol, a ret- mammographic follow-up was available in the remaining nine rospective analysis was performed on all patients referred to our cases . Office notes, radiologic imaging studies, and histologic department for a breast stereotactic core biopsy from January, results were reviewed . 2005 through December, 2007 . All biopsies performed were for calcifications . An 11 or eight gauge vacuum-assisted device was Results: The 28 cases of either intraductal papilloma or papillo- used . Pathology reports were reviewed and only patients with matosis which proceeded to excisional biopsy or mastectomy isolated flat epithelial atypia on core biopsy were included in our revealed a benign diagnosis in 24 (85 7%). cases, atypical ductal study population . Any cases with associated ductal carcinoma in hyperplasia in three cases (10 .7%), and ductal carcinoma in situ/ situ, atypical ductal or lobular hyperplasia, or lobular carcinoma atypical ductal hyperplasia/lobular carcinoma in situ in one case in situ on core biopsy were excluded . Surgical pathology of the (3 6%). . No invasive carcinoma was found . The remaining nine study population was reviewed when available, to assess for cases with initial diagnosis of intraductal papilloma or papilloma- association with worse pathology on excision . tosis which had a minimum of 24 months mammographic fol- low-up were assigned BIRADS category I or II on all subsequent Results: There were 264 stereotactic core biopsies performed mammograms . during our study period . Of these, 16 (6%) had isolated flat epi- thelial atypia on pathology . Pathology from surgical excision was Conclusion: In our study of percutaneously diagnosed intraduct- available for 12 of the 16 (12/16; 75%) . None of the 12 (0/12; al papillomas or papillomatosis, surgery revealed associated high 0%) had change in diagnosis to carcinoma . A change in diagno- risk lesions in 14% of cases and no invasive carcinomas . Our sis to atypia was noted in three patients (3/12; 25%; one atypi- patients without surgical excision who underwent only mammo- cal ductal hyperplasia and two atypical lobular hyperplasia), who graphic follow-up remained asymptomatic and had subsequent also had a change in management and were started on hormo- BIRADS category I or II mammograms . However, due to the asso- nal therapy . Of the remaining nine, six (6/12; 75 %) had calcifi- ciation with high risk lesions, surgical excision of benign papillary cations associated with benign breast tissue and three had more lesions may be warranted . flat epithelial atypia on excision . Of the four patients without available surgical excision pathology, two were lost to follow up and two declined surgery and had stable mammographic find- E011. Effectiveness of Screening Women at High Risk for ings on follow up (one for six months and one for 18 months) . Breast Cancer with Alternating Mammography and MRI (CME Credit Available) Conclusion: Data from our small series suggests that if isolated Le-Petross, H.; Atchley, D.; Whitman, G.; Hortobagyi, G.; Arun, B. flat epithelial atypia is found on core biopsy, surgical excision University of Texas M.D. Anderson Cancer Center, Houston, TX should be performed, since management changes . Though none Address correspondence to H. Le-Petross (huong.le-petross@di. of our cases were upgraded to carcinoma, 25% (3/12) had a mdacc.tmc.edu) change in diagnosis to atypia with change in management . In a small subset if hormonal therapy is not contemplated or con- Objective: MRI has been found to be more sensitive than mam- traindicated a close mammographic follow-up could be consid- mography (M) in the detection of breast cancer (BC), and has ered . been introduced as an adjunct to an annual screening mammo- gram and clinical examination (CE) in women at high risk for developing BC . We investigated the efficacy of alternating screen- ing M with MRI every six months in women at high risk for devel- oping BC .

Materials and Methods: A retrospective chart review was per- formed on 334 patients from the high risk clinic at one institu-

178 El e c t r o n i c Ex h i b i t s : Breast tion, from 1997 to 2007 . Patients with increased risk for BC and disorders which increase lifetime risk of breast cancer . There is had an MRI were included in this study . Women with hereditary insufficient evidence currently regarding screening in women with breast and ovarian cancer syndrome, personal breast cancer his- heterogeneously dense or very dense breasts . Here we present a tory, a biopsy of atypia or lobular carcinoma in situ (LCIS), or a series of cases where mammographically occult malignancies 20% or higher lifetime risk of developing BC by the Gail model were discovered only through breast MR imaging . We will review were included . M, ultrasound (US), MRI findings, and biopsy the indications for breast MRI and the kinetic curves and mor- results were reviewed . phology of malignant vs . benign breast masses found on MRI .

Results: Eighty-six of 334 (26 %) patients underwent annual Educational Goals/Teaching Points: The teaching points will screening M and MRI, with M and MRI alternating every six include: indications for breast MRI as indicated by the recent liter- months . The remaining 248 patients underwent prophylactic ature; kinetic curves of malignant vs . benign breast masses on or were treated with chemoprevention . CE was MRI, and morphologic appearance of suspicious enhancing performed every six months . A total of 47% of 86 patients com- lesions on MRI . pleted the first round of MRI surveillance, 32% completed the second round, 15% completed the third round, and 6% complet- Key Anatomic/Physiologic Issues and Imaging Findings/ ed the fourth round . Of 86 patients who underwent MRI screen- Techniques: The exhibit will cover strengths and weaknesses of ing, 70 had BRCA mutations, and 16 had a history of BC, a biopsy mammography vs . breast MRI; indication for breast MRI imaging, of atypia or LCIS, or a 20% or higher lifetime risk of developing and enhancement kinetics and morphology of breast malignancies . BC . The median follow-up period was two years (range, one to four years) . Nine cancers (six invasive ductal, one invasive lobular, Conclusion: Detecting breast cancer on mammography may be and two ductal carcinoma in situ [DCIS]) were detected in seven difficult in certain cases . MRI as an adjunct to mammography has of 86 (8 1%). . Two women had bilateral cancers . Among the nine been shown to be valuable in the evaluation of breast cancer, as cancers, four (44%) were identified by MRI but not by M, four some breast malignancies are only detected on MR imaging . (44%) were identified by both M and MRI, and one (11%) was Understanding current indications for breast MRI, characteristics not identified by M or MRI . No cancer was seen by M only . Of the of suspicious lesions on MRI, and the limitations of imaging with nine tumors, eight cancers were detected by MRI (sensitivity of breast MRI are vital for cancer detection . 89%) . One cancer was identified by mastectomy only (1 mm focus of DCIS) . In four of the eight MRI detected-cancers, M per- formed six months earlier was normal or demonstrated benign E013. Mammary Fibromatosis (CME Credit Available) findings . The mean size of the cancers was 10 .4 mm (range, 1 to Conners, A.; Glazebrook, K.; Reynolds, C.; Boughey, J. Mayo Clinic, 25 mm) . Metastatic ipsilateral axillary adenopathy was seen Rochester, MN in three of the nine cancer cases . Address correspondence to K. Glazebrook (glazebrook.katrina@ mayo.edu) Conclusion: In women at high risk for developing BC, alternating M and MRI at six month intervals demonstrated that no cancers Background Information: Mammary fibromatosis is a rare, were detected by M only . Future prospective studies should be benign stromal tumor of the breast, comprising less than 0 2%. of performed to evaluate screening with annual M and MRI, alter- all breast tumors . Although benign, this tumor is locally aggres- nating at six month intervals, vs . annual MRI alone . sive and may recur in up to 29% of cases . It presents clinically as a palpable mass, suspicious for malignancy . Dimpling or retrac- tion of the skin may be present and the mass may be adherent E012. MRI Detected Breast Cancers with False Negative to the chest wall . Mammary fibromatosis may occur sporadically Mammograms but also may occur after trauma or a previous surgical procedure, Merchant, K.; Masuda, E.; Fundaro, G.; Beydoun, N. Henry Ford such as or breast augmentation with saline or Hospital, Detroit, MI silicone implants . It is may also be associated with familial ade- Address correspondence to E. Masuda ([email protected]) nomatosis polyposis syndrome . This exhibit illustrates the imag- ing findings and the clinical presentation, with pathologic correla- Background Information: Mammography is the standard of tion, of mammary fibromatosis . care for detecting breast cancer with annual screening beginning in women at age 40 . However, 10% of malignancies are mam- Educational Goals/Teaching Points: The educational goal of mographically occult and are only found clinically . Evaluation for this exhibit is to describe the imaging findings and clinical pres- breast cancer on mammography, in particular, is limited by the entation, with pathologic correlation, of mammary fibromatosis . density of the fibroglandular tissue . Contrast-enhanced MRI has been shown to have high sensitivity for detecting breast cancer Key Anatomic/Physiologic Issues and Imaging Findings/ with its excellent soft tissue contrast, as well as uptake and wash- Techniques: Mammographically, mammary fibromatosis may out characteristics with gadolinium contrast-enhanced breast MRI . present as a spiculated mass that is suspicious for malignancy Mammographically occult lesions seen by MRI have been report- BIRADS 5 . On sonography, fibromatosis appears as a solid, spicu- ed in 27 to 37% of patients . Sensitivity for MRI for breast cancer lated, irregular hypoechoic mass that is highly suspicious for ranges from 88 to 95% in larger single center studies . There are malignancy (BIRADS 5) . Involvement of the pectoralis muscle or various indications for breast MRI including evaluation of known intercostal muscles may be identified . MRI is the best imaging breast cancer, and as screening for patients with a BRCA gene technique for evaluating tumor extent and, in particular, chest mutation, a 20 to 25% or greater lifetime risk of breast cancer as wall involvement . The masses are typically irregular and are isoin- defined by the BRCAPRO or BOADICEA model, history of chest tense to muscle on T1-weighted images and of variable high-sig- irradiation between ages 10 to 30 years, and certain hereditary nal intensity on T2-weighted images . After treatment, areas of

179 El e c t r o n i c Ex h i b i t s : Breast decreased T1 and T2 signal intensity develop, suggesting Educational Goals/Teaching Points: This exhibit will review the decreased cellularity and increased dense fibrosis . The enhance- MRI features that lead to the classification of a lesion as “proba- ment pattern is generally one of a benign progressive enhance- bly benign”, and review how frequently this classification is uti- ment, as opposed to the typical wash-out kinetics of breast carci- lized . In the literature, the frequency of “probably benign” inter- noma . pretations range from 6 .6 to 24% of MR exams receiving at least one recommendation for a six-month follow-up MR . It will also Conclusion: Mammary fibromatosis is a rare, benign, nonmetas- review follow-up recommendations and patient compliance tasizing stromal tumor . It is locally aggressive with infiltrative mar- rates . Follow-up recommendations include MR in six months or gins and has a high recurrence rate . Clinically and on imaging, it mammography or targeted ultrasound with short-term follow-up mimics malignancy . MRI is helpful for determining tumor extent MR if the lesion is sonographically occult . Compliance is variable, and chest wall invasion . The histopathologic differential diagnosis ranging from 63 to 86% of patients returning for follow-up MR . It is broad and ranges from reactive processes to malignant ones . will review outcome of follow-up imaging, including review if the Complete surgical excision is the treatment of choice . findings were downgraded to a BIRADS 1 or 2 based on resolu- tion or stability of MR findings, unchanged as BIRADS 3 or upgraded to a BIRADS 4 with biopsy recommended, and it will E014. Pearls and Pitfalls in MRI-Guided Breast Biopsy identify the cancer yield in lesions initially assessed as BIRADS Ojeda-Fournier, H.; Comstock, C.; Middleton, M. University of 3 The. cancer yield exhibits ranges from 0 6-10%,. with the highest California, San Diego, San Diego, CA cancer yield in high-risk women . The pathology of these cancers Address correspondence to H. Ojeda-Fournier (ojeda-lowy@ includes ductal carcinoma in situ (DCIS) and infiltrating ductal sbcglobal.net) carcinoma .

Background Information: Contrast-enhanced breast MRI finds Key Anatomic/Physiologic Issues and Imaging Findings/ lesions not visible by other modalities . The ability to perform MR Techniques: This exhibit will review the literature to determine intervention is essential for any facility that performs high quality the morphologic and kinetic features of lesions that were classi- contrast-enhanced breast MR . In summary, the technique, proce- fied as “probably benign” . Specific features include: solitary vs . dure, pitfalls and pearls are illustrated in this educational exhibit . multiple lesions, mass vs . non-mass lesions, margin characteris- tics, internal enhancement patterns, and time-signal intensity Educational Goals/Teaching Points: This exhibit will discuss curves . It will identify which features were most frequently seen the indications for MR guided interventional procedures; illustrate with true benign lesions and those associated with a malignancy . how to perform MR-guided intervention with photographs, dia- grams and short cine clips and review pearls and pitfalls associat- Conclusion: A “probably benign” interpretation is assigned to 6 .6 ed with MR-guided breast intervention . to 24% of breast MR exams with 63 to 86% of patients returning for follow-up MR . The cancer yield ranges from 0 .6-10% . Key Anatomic/Physiologic Issues and Imaging Findings/ Evidenced-based criteria for “probably benign” lesions on breast Techniques: The exhibit will describe MRI-guided vacuum-assist- MRI needs to be established to decrease the chance of a false- ed core biopsy and needle localization techniques of lesions negative lesion being assigned a MR BIRADS 3 classification . found at contrast-enhanced dynamic MRI of the breast, and not seen by mammography, ultrasound, or clinical evident . E016. MRI-Guided Breast Procedures in Less than 45 Conclusion: Contrast-enhanced breast MRI finds lesions not visi- Minutes: Practical Tips and Tools for Troubleshooting ble by other modalities . The ability to perform MR intervention is (CME Credit Available) essential for any facility that performs high quality contrast-en- Chhor, C.; Chang, B.; Tso, H.; Proctor, E.; Hylton, N.; Joe, B. hanced breast MR . In summary, the technique, procedure, pitfalls University of California, San Francisco, San Francisco, CA and pearls are illustrated in this educational exhibit . Address correspondence to B. Chang ([email protected])

Background Information: Increasing numbers of breast MRI E015. Review of Probably Benign Lesions Detected at Breast studies are being performed for screening of high risk women MRI (CME Credit Available) and pre-operative evaluation of extent of disease . Given the limit- Mango, V.; Mercado, C.; Lee, J.; Toth, H.; Moy, L. New York ed specificity of breast MRI, this has led to an increased number University, New York, NY of breast procedures, which include wire-localization and biop- Address correspondence to V. Mango (victoria.mango@gmail. sies . Efficient, safe, and accurate methods of performing MRI- com) guided breast procedures of lesions not visible by mammography or second-look ultrasound are needed . The purpose of this Background Information: BIRADS 3 “probably benign” imaging exhibit is to describe efficient techniques for performing MRI- characteristics for mammography are well defined and reflect an guided breast procedures, particularly when there are multiple expected cancer yield of < 2% . Specific imaging features for MRI sites or bilateral breasts are involved . Practical tips for trouble- detected lesions placed in this category are not clearly defined . shooting problems with imaging or biopsy equipment will be The ACR describes MR BIRADS 3 lesions as having a “very high presented with case examples . probability of being benign” and states most approaches to this category are currently “intuitive” . Our objectives are to identify Educational Goals/Teaching Points: We will review indications lesions classified as “probably benign” on MRI, review the follow- for MRI-guided breast procedures and how to perform MRI- up compliance and frequency of subsequent malignancy . guided breast procedures utilizing various methods, needle devices, and targeting software . In addition we will suggested

180 El e c t r o n i c Ex h i b i t s : Breast workflow for a safe, efficient, and successful procedure; and how sequences included pre- and postcontrast-enhanced (0 1. mmol to troubleshoot common imaging pitfalls including: a) fat-satura- gadobenate dimeglumine/kg) 3D axial gradient-recalled echo tion problems with water-saturation of breast tissue; b) what to dynamic examinations . do when your targeting software fails, when grid obstructs nee- dle placement, and if lesion is outside of grid; and c) how to Results: Serum progesterone concentration of < 1 .5 ng/mL was sequence procedures involving different means of guidance, such used to define the follicular phase of the and as MRI, mammographic, and ultrasound, required in the same appropriately time the breast MRI examination for all 11 premen- patient . opausal women without cyclical menses . None of the women required a repeat examination because of disproportionate Key Anatomic/Physiologic Issues and Imaging Findings/ enhancement of normal glandular tissue . Techniques: We will illustrate safe, efficient, and accurate tech- niques for performing MRI-guided breast procedures with the fol- Conclusion: Serum concentrations of progesterone correspond- lowing case examples: 1) biopsy at three different sites in the ing to the follicular phase of a normal menstrual cycle can aid in same breast (performed under 60 minutes); 2) positioning tricks optimal scheduling of breast MRI examinations for premenopau- to reach far posterior breast lesions; 3) wire localization of sal women who do not have a normal menstrual cycle . lesions outside of the grid; 4) fat-saturation failure with water- saturation of breast tissue (presentation of troubleshooting tips and resultant improved images); 5) targeting lesions when soft- E018. Preoperative Breast MRI for Prediction of Occult ware fails; and 6) sequencing of procedures when MRI, US and Invasive Disease (CME Credit Available) mammographic guidance is required in the same patient . Jakubowski Wisner, D.; Chang, B.; Flowers, C.; Joe, B.; Lessing, J.; Gibbs, J.; Itakura, K.; Hwang, S.; Hylton, N. University of California, Conclusion: MRI-guided breast procedures are an important San Francisco, San Francisco, CA adjunct to the diagnosis and management of breast cancer . They Address correspondence to D. Jakubowski Wisner (dorota.wisn- can be performed efficiently, safely, and accurately using tech- [email protected]) niques presented here . Objective: The objective was to assess utility of preoperative MRI for evaluation of occult invasive disease in women with an initial E017. Optimal Timing of Breast MRI Examinations for core-biopsy diagnosis of ductal carcinoma in situ (DCIS) . Premenopausal Women Who Do Not Have a Normal Menstrual Cycle Materials and Methods: A comprehensive search of University Ellis, R. Gundersen Lutheran Medical Center, La Crosse, WI of California-San Francisco pathology and radiology archives Address correspondence to R. Ellis ([email protected]) spanning 2000-2007 was performed in order to identify all women with a core biopsy revealing pure DCIS, who also Objective: The purpose of the study was to determine whether obtained preoperative MRI prior to surgery at UCSF . Neoadjuvant our practice of using serum progesterone concentrations corre- therapies were excluded . Patients with a biopsy diagnosis of sponding to the follicular phase of the menstrual cycle to time microinvasive disease, history of ipsilateral invasive cancer in the breast MRI examinations in premenopausal women without past two years, or recent (within six months) ipsilateral breast cyclical menses reduced the number of nondiagnostic and false- surgery were also excluded . In order to avoid the possibility of positive results . Delille et al . found that performing scans during disease progression, inclusion required that final surgery occur the follicular phase of the menstrual cycle (days 3-14 of a normal within six months of the core biopsy . A breast MRI-trained radiol- 28-day menstrual cycle) minimized uptake of gadolinium in nor- ogist blinded to the surgical results was given the location of the mal breast tissue that can render dynamic breast MRI examina- primary lesion as marked by biopsy clip or estimated biopsy loca- tions difficult to interpret, resulting in significant numbers of tion, and asked to categorize the lesion . Radiologist prediction of false-positive results or in nondiagnostic examinations . Women invasive disease was compared to surgical pathology . lacking a normal cyclical menses upon which to base optimal timing of MRI examinations include, (a) premenopausal women Results: To date, 36 MRI studies have been evaluated . In this who have undergone a hysterectomy but retain normally func- study group, 58% (21) proceeded to and 42% (15) tioning ovaries; (b) premenopausal women with induced irregu- proceeded to mastectomy . Of the original 36 cases initially diag- lar menstrual cycle due to oral or injectable contraceptives; (c) nosed as DCIS, nine (25%) were found to have invasive disease premenopausal women undergoing chemotherapy with induced and three patients (8%) had no remaining disease at surgery . In perimenopausal status; and (d) perimenopausal women with the remaining 24 cases, 13 (36% of total population) were found irregular menstrual cycles . to have intermediate-high or high grade DCIS and 11 (31% of the total population) had low to intermediate grade DCIS . When Materials and Methods: We conducted a retrospective, single- asked to rate probability of invasive disease on the preoperative institution review of our center for breast care database to identi- MRI, the reader categorized 17 cases (47%) as “no invasive can- fy all patients who had breast MRI scans between February 5, cer,” 16 of which were accurately categorized and one of which 2006 (the date we first used progesterone concentrations to time contained a 2 mm invasive ductal carcinoma . All other cases of breast MRI scans in premenopausal women without cyclical invasive disease were captured within “possible” (five) or “proba- menses) and July 16, 2008 . We further identified those patients ble” (three) categories . Radiologist sensitivity for invasive disease for whom serum progesterone concentrations had been obtained was 89% (CI: 52-100%), specificity 59% (38-78%), positive pre- and used to time the breast MRI examination . All the breast MRI dictive value 42% (20-66%), and negative predictive value 94% examinations were performed using a 1 5T. scanner and software (71-100%) . (Siemens Medical Solutions, Erlangen, Germany) Scanning

181 El e c t r o n i c Ex h i b i t s : Breast

Conclusion: Initial results suggest radiologist prediction is sensi- E020. Ultrasound of the Pregnant and Immediate tive for presence of occult invasive disease, although specificity is Postpregnant Breast: Frequent and Less Common poor . As negative predictive value is high (94%), a negative pre- Conditions (CME Credit Available) operative MRI may be very helpful for stratifying patients into low Majewski, S.; O’Connell, A. University of Rochester Medical Center, and high risk groups for occult invasive disease, ultimately assist- Rochester, NY ing the decision of whether to proceed to sentinel lymph node Address correspondence to S. Majewski (Sara_Majewski@urmc. biopsy . rochester.edu)

Background Information: Normal breast findings in E019. Fat Suppression for Breast MRI Improves by Fast 3D and postpregnancy are secondary to hormonal stimulation . The Dual Echo Dixon Technique (CME Credit Available) majority of entities affecting the breasts at these times are similar Le-Petross, H.; Kundra, V.; Szklaruk, J.; Wei, W.; Andreopoulou, E.; to those in the nonpregnant state . Several findings are only seen Ma, J. University of Texas M.D. Anderson Cancer Center, Houston, in the pregnant, postpregnant and lactating states . Ultrasound is TX the best modality for evaluating the breast in pregnancy and Address correspondence to H. Le-Petross (huong.le-petross@di. postpregnancy . mdacc.tmc.edu) Educational Goals/Teaching Points: The exhibit will describe Objective: MRI is becoming an important imaging modality in ultrasound findings exclusive to pregnant and postpregnant the detection and diagnosis of breast diseases . The fat suppres- patients, including , cellulitis, , abscess and lac- sion quality of the imaging sequences used in a breast MRI exam tating adenoma; describe ultrasound findings of other abnormali- (bMRI) is essential to allow differentiation of enhancing lesions ties common in pregnancy such as fibroadenoma, pseudoangi- from the background fatty tissue . The purpose of our study is to omatous stromal hyperplasia (PASH) and diabetic mastopathy, compare the images of the contrast-enhanced dual echo Dixon and emphasize the awareness of carcinoma which, although rare, (cDixon) technique with the standard 3D spoiled gradient echo is the most devastating diagnosis to be made in pregnancy . technique or volume imaging for breast assessment (VIBRANT), commonly used for breast MRI . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The viewer of the exhibit will be learn the normal Materials and Methods: The institutional review board anatomy of the breast, be able to describe the physiologic chang- approved this Health Insurance Portability and Accountability Act- es occurring in the pregnant and postpregnant breast and learn compliant study . Informed consent was obtained from all advantages and disadvantages of ultrasound in imaging the preg- patients . The VIBRANT and the cDixon techniques were per- nant and postpregnant breast compared to other modalities . formed of both breasts, after IV gadolinium-enhanced dynamic series of a standard bMRI exam . Three radiologists independently Conclusion: The pregnant and postpregnant breast presents with reviewed the deidentified images . The radiologists rated the both unique findings, as well as common entities seen in all image quality in five categories (scale: 1 poor, 2 fair, 3 good, 4 women, which are best imaged by ultrasound . excellent): quality of the fat saturation, the uniformity of fat satu- ration, the visibility of the index lesion, the margin clarity of the index lesion, and the visibility of the axillary region . For quantita- E021. Mixed Echogenicity Breast Masses: A Pictorial Review tive assessment, the signal-to-noise ratio (SNR), contrast-to-noise of Imaging Findings with Pathologic Correlation (CME ratio (CNR) of lesion to breast, SNR efficiency (SNReff), and CNR Credit Available) efficiency (CNReff) were calculated . Guelfguat, M.; Hazany, S.; Wrzolek, M.; Buchbinder , S. Staten Island University Hospital, Staten Island, NY Results: Nineteen patients agreed to participate in this study; Address correspondence to S. Hazany ([email protected]) 13/19 patients had a primary breast malignancy (11 invasive car- cinoma and two ductal carcinoma in situ) and 6/19 patients had Background Information: Ultrasound is an established modality benign lesions or negative exams . The Dixon images were rated employed for characterization of breast masses . higher in four of the five qualitative categories: quality of fat satu- ration, uniformity of fat saturation, margin clarity of index lesion, Educational Goals/Teaching Points: In this educational exhibit and visibility of the axilla (p<0 .0001) . The cDixon images yielded we hope to: 1 . illustrate sonographic features of different benign significant higher SNR (43 8). and CNR (40 1),. compared to the and malignant mixed echogenicity breast lesions; 2 . review imag- VIBRANT images (SNR=34 .8, CNR=25 .3), p<0 .05 . The SNR and ing features and histopathologic correlation of several common CNR efficiency for the cDixon (SNR=36 .3, CNR=33 .79) were also and rare mixed echogenicity breast masses, and 3 . emphasize higher than the VIBRANT (SNR eff=25 .7, CNR eff=19 .1), p<0 05. . diagnostic difficulties, potential pitfalls, and differential diagnoses Furthermore, the Dixon technique required shorter scan time to of these entities . achieve these improvements . Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: The images of the Dixon technique were superior to Techniques: Sonographic features of mixed echogenicity breast the standard VIBRANT technique in both qualitative and quantita- lesions will be reviewed and correlated with mammographic tive assessment of 19 breast MRI cases . The Dixon technique appearance and pathologic characteristics of various cancers, such could replace the standard VIBRANT technique, for improved as metaplastic carcinoma, tubular carcinoma, metastatic cancer to contrast-enhanced breast MRI, in future studies with larger sam- the breast, phylloides tumor, granular cell tumor, tubular adeno- ple size . ma, nodular lobular hyperplasia, complex sclerosing papillary lesion, lipoma, epidermal inclusion , sclerosing adenosis, fibro-

182 El e c t r o n i c Ex h i b i t s : Breast sis, , proteinaceous cyst, pseudoangiomatous stromal Conclusion: Our goal is to demonstrate a decrease in the hyperplasia (PASH), epidermal inclusion cyst, fibroadenoma . number of sentinel node biopsies due to preoperative axillary ultrasound evaluation and biopsy and to assess the sensitivity Conclusion: The main teaching point of this exhibit is to provide of ultrasound-guided biopsy in preoperative staging across a a pictorial review of diverse pathologic entities, benign and range of tumor sizes . malignant, appearing as mixed echogenicity breast lesions . The exhibit will discuss specific imaging and pathologic characteristics of several rare and common mixed echogenicity breast masses . E023. 3D and 4D Ultrasound of the Breast: What Kind of Familiarity with mixed echogenicity breast lesions aids in the for- Additional Information Can it Provide Over Conventional 2D mulation of complete differential diagnosis . Appropriate biopsy Ultrasound in the Diagnosis and Intervention of Breast strategies will be discussed . Lesions? Lee K.1; Woo O.1; Cho K.2; Seo B.3; Yong H.1; Kim A.1; Kang E.1 1. Korea University Guro Hospital, Seoul, South Korea; 2. Korea E022. Preoperative Axillary Ultrasound and Biopsy in the University Anam Hospital, Seoul, Korea; 3. Korea University Ansan Evaluation of Women Diagnosed with Breast Cancer Hospital, Seoul, Korea Larsen, L.1; Kuo, J.1; Bickell, K.1; Soetaert, A.1; Fraley, J.1; Address correspondence to O. Woo ([email protected]) Andrews-Tang, D.2; Yamashita, M.1; 1. University of Southern California School of Medicine, La Canada, CA; 2. Olive View- Background Information: 3D and 4D ultrasound may provide University of California-Los Angeles Medical Center, Sylmar, CA new perspectives in the field of . Consequently, Address correspondence to L. Larsen ([email protected]) we look forward to offering new diagnostic information and potentially improved characterization of breast lesions . Background Information: Axillary lymph node status is the sin- gle most important prognostic factor in women with invasive Educational Goals/Teaching Points: The goals are to present breast cancer . Currently, the standard of reference for evaluating variable techniques and differences in 3D and 4D ultrasound of the axilla is axillary lymph node dissection (ALND) . However, the breast; demonstrate various breast lesions with pathologic since this procedure can cause many postoperative problems, correlation, and to evaluate the diagnostic accuracy of 3D and 4D ALND has largely been replaced by sentinel lymph node biopsy ultrasound in comparison with 2D ultrasound . (SNB) in clinically-determined node-negative women . More recently, ultrasound (US) has been used as a noninvasive meth- Key Anatomic/Physiologic Issues and Imaging Findings/ od for evaluating the axilla and has been successful in predicting Techniques: This exhibit will focus on 3D and 4D ultrasound, nodal status . Ultrasound-guided biopsy (UGB) is often performed and techniques and differences and 3D and 4D ultrasound imag- when a suspicious lymph node is identified . Women who have a es related normal anatomy . It will provide an overview of 3D positive UGB will directly undergo an ALND without SNB, avoid- and 4D breast ultrasound imaging, including information on ing the additional cost and time of SNB . : morphology, volume calculation; papillary neo- plasm: in association with adjacent duct and malignant tumor: This study is a retrospective review of 270 women diagnosed morphology, extent including adjacent duct involvement, staging . with invasive breast cancer at our centers from January, 2006 Additional information will be provided over 2D ultrasound that to October, 2008 . Our goal is to assess the accuracy of ultra- aids in the diagnosis and intervention of breast lesions sound in predicting nodal status in these women in order to improve detection and decrease the number of operative proce- Conclusion: Major advantages of 3D and 4D ultrasound of the dures required for staging . Each woman had a preoperative axil- breast is its capability to generate multisectional planes and pro- lary ultrasound and biopsy if the lymph node was suspicious . The vide volumetric data of the lesion . Furthermore, the coronal nodal status assessed by ultrasound with or without biopsy is plane provides additional information that assists in differentiat- compared with final pathology results . Sonographic parameters ing benign and malignant tumors and in 3D targeting, it can pro- for each lymph node being evaluated include shape, hilar and vide precise location of biopsy needles in all planes thus provid- cortical morphology, vascularity, and dimensions (longitudinal, ing reassurance to the radiologist . transverse, and hilar diameters) . We will determine the sono- graphic features that best correlate with metastatic lymph nodes and describe the percutaneous biopsy techniques most accurate E025. Value of Ultrasound-Guided Aspiration of Complicated for diagnosis . Breast Cysts in Identifying Malignant Lesions: Retrospective Review (CME Credit Available) Educational Goals/Teaching Points: In this educational exhibit, Ansari, F.; Kaplan, S. Mount Sinai Medical Center, Miami Beach, we will compare the results of preoperative axillary ultrasound FL and biopsy with final pathology in women diagnosed with breast Address correspondence to F. Ansari ([email protected]) cancer . The sonographic features of benign and malignant axillary lymph nodes will be described . We will discuss the different Objective: The objective was to retrospectively review ultra- biopsy techniques used for staging the axilla . sound-guided aspiration of complicated breast cysts to determine the percentage that are solid masses upon aspiration, and to Key Anatomic/Physiologic Issues and Imaging Findings/ determine incidence of malignancy . Techniques: We will correlate the preoperative axillary ultra- sound findings with the pathology results in women with breast Materials and Methods: The breast imaging database at our cancer . We will determine which sonographic paraments corre- institution was reviewed . A total of 449 ultrasound-guided cyst late best with metastatic axillary lymph nodes . aspiration procedures were performed during a one-year period

183 El e c t r o n i c Ex h i b i t s : Breast between September 1, 2007 and August 31, 2008 . The number node margins 5 2,. hilar replacement 4 3. . Results of univariate of aspirations that led to ultrasound-guided core needle biopsy logistic regression predictive a positive pathology . was determined retrospectively . The pathology database was then reviewed to identify the number of benign, high risk, and Variable Sensitivity Specificity Odds P-value malignant entities resulting from the ultrasound-guided core Ratio biopsies . Matting 51 6%. 83 6%. 5 .4 <0 .001 Results: Of the 449 ultrasound guided cyst aspiration proce- dures, 35 led to ultrasound-guided needle biopsies of the pre- Perinodal 34 .4% 86 6%. 3 4. 0 .006 sumed complicated cysts . Twenty-nine of these apparent compli- Unclear 64 .1% 74 .6% 5 2. <0 .001 cated cysts were benign, four proved to be malignant, and two Margins revealed high-risk atypical findings on pathology . The incidence of malignancy of a complicated breast cyst unresolved with ultra- Fatty Hilar 71 .4% 42 .3% 4 .3 0 .004 Replacement sound-guided cyst aspiration in our study is 11 .5% . Fatty Hilar 74 .4% 59 5%. 1 .8 0 20. Conclusion: The risk of malignancy for apparent complicated Effacement cysts that do not resolve upon aspiration attempt is 11 .5% in this retrospective review . Ultrasound-guided cyst aspiration should be Conclusion: The sonographic features of unclear lymph node performed for masses that appear cystic and do not meet the margins, matting, perinodal edema, and hilar replacement have a sonographic criteria for a simple cyst . statistically significant association with ENE . The sonographic fea- tures of unclear node margins, lymph node matting, and perin- odal edema are predictors of ENE with high specificity (75%, E026. Sonographic Features of Extranodal Extension in 84%, 87%) . Axillary Lymph Nodes (CME Credit Available) Misselt, P.; Glazebrook, K.; Reynolds, C.; Degnim, A.; Morton, M. Mayo Clinic, Rochester, MN E027. The Efficacy of Follow-Up Ultrasound in Asymptomatic Address correspondence to K. Glazebrook (glazebrook.katrina@ Patients with Mastectomy mayo.edu) Bae, J.; Kim, H.; Choi, J.; Ryeom, H. Kyungpook national university hospital, Daegu, Korea Objective: The objective was to assess the diagnostic accuracy of Address correspondence to H. Kim ([email protected]) several sonographic features in the prediction of extranodal extension (ENE) in axillary lymph nodes of patients with biopsy- Objective: The objective was to evaluate the efficacy of ultra- proven breast cancer . sonographic (US) follow-up in detecting locoregional recurrences in asymptomatic patients who had mastectomy for breast cancer Materials and Methods: A query of our institutional surgical and to evaluate US findings and clinical variables associated with and pathologic database was performed looking for breast can- a recurrence . cer patients with axillary node sampling between January, 2003 and September, 2007 . Patients without sonographic imaging or Materials and Methods: Between February, 2004 and surgical follow-up were excluded . We also excluded patients December, 2006, we reviewed 1,855 breast US examinations of whose surgical nodal biopsies revealed only isolated tumor cells 899 asymptomatic patients, who showed no clinical evidence of or micrometastases (N0(i)) . The remaining patients (n=131) recurrence after mastectomy for breast cancer in our hospital . were separated into two groups based on the pathology-proven US-guided intervention or excision was taken to confirm the sus- presence or absence of extranodal extension (ENE) . A blinded, picious lesions on US . The US findings of lesions on mastectomy fellowship trained breast imager then reviewed the sonographic site and the clinical variables were correlated with pathologic or images of the axillary lymph nodes with specific attention to the follow-up results . The overall survival for asymptomatic vs . symp- following imaging features: lymph node margins, matting, perin- tomatic recurrent patients was estimated using Kaplan-Meier sur- odal edema, and hilar effacement or replacement . The sensitivity vival analysis . and specificity of predicting a positive pathology for ENE were calculated for each imaging feature . Univariate and multivariable Results: US found 124 lesions (65 masses and 59 lymph nodes) association between these imaging features and ENE were on mastectomy site in 118 patients . Among them, 44 lesions in assessed using logistic regression, reporting the results as odds 43 patients showed suspicious US findings . Pathologic results ratios . revealed 19 malignant lesions (43 .2%) in 18 patients and 25 benign lesions (56 .8%) in 25 patients . The US detection rate of Results: Our search yielded 131 patients, 64 patients with occult recurrence was 2%, (18 of 899 patients) and the overall extranodal extension and 67 patients without extension . The sen- recurrence rate was 2 6%. (23 of 899 patients), including five sitivity and specificity estimates for each sonographic feature as a false negative cases . The not circumscribed margin and thick halo predictor of positive ENE on pathology are as follows: matting of the mass, the larger size, irregular shape, not circumscribed 52% and 84%, perinodal edema 34% and 87%, unclear node margin, calcifications, increased vascularity of the lymph node, margins 64% and 75%, hilar replacement 71% and 42%, and and the number of positive lymph nodes at the time of surgery hilar effacement 74% and 60% . Univariate analysis revealed a were significantly associated with recurrence (p<0 05). . There statistically significant association between each sonographic fea- was significant difference in the overall survival between asymp- ture and pathologically proven extranodal extension with odds tomatic and symptomatic recurrent groups by Kaplan-Meier sur- ratios (OR) as follows: matting 5 .4, perinodal edema 3 4,. unclear vival analysis (p=0 .049) .

184 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Conclusion: Regular US follow-up in asymptomatic patients who had mastectomy for breast cancer is helpful for the early detec- Cardiopulmonary tion of recurrence and this may lead to better prognosis . E029. Use of 3D Imaging Algorithms to Demonstrate the Congenital Abnormalities of the Coronary Arteries E028. Nodal Mapping for Radiation Planning in Primary Oliveira, G.; Branch , K.; Dubinsky, T.; Shuman, W.; Warren, B. Breast Cancer Using Cross Modality Fusion University of Washington, Seattle, WA Islam, T.1; MacDonald, S.2; Oliveira, G.2; Wolfgang, J.2; Taghian, Address correspondence to G. Oliveira ([email protected]. A.2; Harisinghani, M.1 1. Center for Molecular Imaging Research/ edu) Massachusetts General Hospital, Boston, MA; 2. Massachusetts General Hospital, Boston, MA Background Information: The purpose of this exhibit is to dem- Address correspondence to T. Islam ([email protected]. onstrate the congenital abnormalities of the coronary arteries edu) using detailed anatomic illustrations with corresponding recon- structed 3D MR and CT images . Background Information: The purpose of this exhibit is to dem- onstrate the use of cross modality registration techniques to Educational Goals/Teaching Points: Anomalous origins of the develop radiation planning maps for lymph nodes in patients coronary arteries may be clinically benign but may cause arrhyth- with primary breast cancer . mias or myocardial ischemia and result in sudden death, particu- larly in young athletes . Understanding the clinical implications of Educational Goals/Teaching Points: There is currently a lack of the normal anatomy and variants and anomalous origins of coro- robust guidelines and consensus among radiation oncologists nary arteries is very important for the radiologist and clinicians to about anatomical distribution of regional nodes in primary breast understand . The use of 2D and 3D reconstructions and real time cancer . This exhibit demonstrates the use of pooled MRI data movies of the coronary arteries provides a clearer understanding from multiple patients who had undergone lymphotropic nano- of this important anatomy . particle-enhanced MRI with ferumoxtran-10 (AMAG Pharmaceutical, Inc ., Lexington, MA) for nodal staging for devel- Key Anatomic/Physiologic Issues and Imaging Findings/ oping a comprehensive nodal map and subsequently fusing this Techniques: In this exhibit, we will show how 3D reconstruc- to conventional CT for radiation planning purposes . tions in different anatomic planes with associated diagrams and movies can provide a noninvasive demonstration of anatomy that Key Anatomic/Physiologic Issues and Imaging Findings/ can be easily correlated with cross-sectional images . Techniques: Nodal staging is important for prognosis and thera- py in patients with primary breast cancer . Evolving technologies Conclusion: After reviewing this exhibit the observer will have a such as lymphotropic nanoparticle-enhanced MRI with ferumox- clear understanding of how state-of-the-art 3D imaging tech- tran-10 (AMAG Pharmaceutical, Inc ., Lexington, MA) allow us to niques are beneficial in the study of cross-sectional anatomy of improve the accuracy in distinguishing benign from malignant congenital abnormalities of the coronary arteries . lymph nodes .

Conclusion: After reading this exhibit the viewer will understand E030. Coronary Artery Noninvasive Imaging in Adult the nodal drainage sites for primary breast cancer and how this Kawasaki Disease (CME Credit Available) information can be useful for accurate radiation therapy planning . Cantin, L.1; Chartrand-Lefebvre, C.1; Marcotte, F.2; Pressacco, J.2; Ducharme, A.2; Lapierre, C.3 1. University of Montreal Medical Center, Montreal, Canada; 2. Montreal Heart Institute, Montreal, Canada; 3. Sainte-Justine hospital, Montreal, Canada Address correspondence to C. Chartrand-Lefebvre (chartrandlef@ videotron.ca)

Background Information: Coronary artery aneurysms, stenoses and thromboses are significant complications of Kawasaki dis- ease (KD) . While appearing in childhood, coronary complications are often left unrecognized until early and mid-adulthood . Along with the increasing capacity of noninvasive coronary artery imaging modalities, especially CT and MRI, radiologists are more likely to face the diagnosis of KD in adults .

Educational Goals/Teaching Points: The goal is to review the clinical aspects of KD for radiologists, and to compare coronary imaging modalities in the diagnosis of KD .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: (US) is particularly useful in young patients with KD, since aneurysms usually occur in prox- imal coronary arteries, which is an accessible region in children . Abnormal findings include an artery diameter > 3 mm, lack of normal tapering and perivascular bright echoes . Chest X-ray in 185 El e c t r o n i c Ex h i b i t s : Cardiopulmonary the acute phase can demonstrate cardiomegaly consistent with Conclusion: Coronary artery imaging will become even more pericardial effusion, and calcification of coronary artery aneur- important as we move beyond 64-slice CT to near real time ysms during follow-up . MR angiography allows a safe evaluation acquisition . The techniques described in this exhibit will be of proximal coronary arteries, reducing radiation dose in very important regardless of the advances in data acquisition and an young patients . MR evaluation of coronary artery aneurysms in understanding of them is critical for clinical practice . patients with KD is good, but is less adequate in the evaluation of stenosis or thrombosis . 64-slice MDCT coronary angiography can depict complex abnormal morphology of the coronary tree, E032. Coronary Plaque Quantification by Voxel Analysis as well as stenoses, occlusions and calcifications . It is especially Using MDCTA: Validation with useful for visualization of the distal coronary tree, an often blind Khosa, F.; Sarwar, S.; Brodoefel, H.; Sabir, A.; Yam, C.; Clouse, M. area for US and MR . CT seems superior to MR for aneurysm Beth Israel Deaconess Medical Center, Brookline, MA visualisation, and especially for stenosis and thrombosis detec- Address correspondence to F. Khosa ([email protected]) tion . Imaging protocols using ECG-dose modulation or prospect- ive ECG-gating, along with beta-blockade, should reduce radia- Objective: The objective was to evaluate a voxel based analysis tion dose . Catheter angiography can be reserved for complicated technique for quantification of non-calcified coronary plaque, or inconclusive cases or for interventions . using intravascular ultrasound (IVUS) as a standard of reference .

Conclusion: In the childhood acute phase, US is the modality of Materials and Methods: IVUS and dual-source MDCTA were choice for coronary artery imaging in KD . After childhood, CT and prospectively performed in 12 patients, resulting in identification MRI should be used . MR angiography allows a safe evaluation of of 20 segments containing noncalcified plaque . Four of these proximal coronary arteries, reducing radiation dose in very young segments were used to establish reference measurements of 0 .6 patients with KD . CT seems superior to MR for aneurysm mm proximal wall thickness using a 0 HU cut-off between epi- visualisation, and especially stenosis and thrombosis detection . cardial fat and outer wall; and an individually adjusted threshold Reducing radiation dose is a primary concern and imaging proto- for the interface between wall and lumen . Using these data, con- cols using ECG-dose modulation or prospective ECG-gating, along secutive circular layers of outer wall were subtracted from a 3D with beta-blockade, should be considered . Catheter coronary volume to determine the plaque plus media and the actual artery angiography can usually be reserved for complicated cases, plaque volume in the remaining 16 segments . Accuracy of the or when interventions are planned . voxel technique was assessed by comparing the results with IVUS . This study was IRB approved and patients provided written consent . E031. Evaluation of Coronary Artery CT Angiograms: A Practical Approach (CME Credit Available) Results: Both the plaque plus media layer and the actual plaque Fishman, E. Johns Hopkins Hospital, Owings Mills, MD volume showed good concordance to IVUS (49 6. ± 20 mm3 vs . Address correspondence to E. Fishman ([email protected]) 56 .7 ± 23 .6 mm3, p=0 .076; 26 .5 ± 14 .8 mm3 vs . 30 .9 ± 15 .3 mm3, p=0 09). . Corresponding correlation coefficients were Background Information: The evaluation of the coronary arter- r=0 76. and r=0 .79 . The method offered good reproducibility with ies with CTA is one of the hottest topics in radiology today . The intraclass-correlation-coefficients being 0 93. for total plaque bur- literature provides a success rate of nearly a 99% negative pre- den and 0 .90 for the genuine plaque volume . dictive value and an 89-92% positive predictive value . Some of the criticism of this data is small study series and a lack of robust Conclusion: Voxel analysis provides accurate and reproducible criteria for data analysis . To date there is no clear published con- quantification not only for plaque plus media volume but also for sensus on how to evaluate the studies and authors use tech- true plaque volume . niques ranging from axial imaging to multiplanar reconstruction to curved planar reconstruction to sliding MIPs, to volume ren- dering to analyze the data . In this exhibit we will review each of E033. Prevalence and Clinical Significance of Noncoronary the options and define the advantage and disadvantage of each Ancillary Findings on Coronary Artery Calcium Scoring CT technique . Select case studies will be provided to illustrate each (CME Credit Available) of the points made and a scheme for a logical approach to these Akhtar, N.; Aktay, R.; Ciancibello, L.; Orringer, C.; Sachs, P.; datasets will be provided . Gilkeson, R. University Hospitals–Case Medical Center, Lakewood, OH Educational Goals/Teaching Points: The viewer of the exhibit Address correspondence to N. Akhtar ([email protected]) will learn the advantages and disadvantages of axial imaging, multiplanar reconstruction, curved planar reconstruction, sliding Objective: The objective was to estimate the prevalence and MIPs and volume rendering for imaging the coronary arteries and clinical significance of noncoronary ancillary findings on coronary be able to develop a logical scheme for the analysis of coronary artery calcium scoring CT . artery datasets . Materials and Methods: A retrospective review was made of Key Anatomic/Physiologic Issues and Imaging Findings/ 1,000 consecutive patients who underwent coronary artery calci- Techniques: Key issues include analysis of coronary anomalies; um scoring CT between October, 2007 and July, 2008 in our analysis of coronary artery stenosis; the role of axial imaging, multi- institutional-wide screening initiative, “EDUCATE” (Early Detection planar reconstruction , curved planar reconstruction, sliding MIPs Using Calcium Scoring for Treatment and Elimination of Coronary and volume rendering for imaging the coronary arteries and how to Heart Disease) . Studies were performed on dual source CT or develop a logical approach to the analysis of the coronary arteries . 16-slice or 64-slice MDCT scanners and interpreted by one of

186 El e c t r o n i c Ex h i b i t s : Cardiopulmonary three radiologists . Noncoronary ancillary findings and correspond- defects will be explained with images . Useful techniques for ing imaging and clinical recommendations and follow-up were identifying and compensating for these artifacts include verifica- reviewed . tion of anatomic distribution and relation to coronary supply, slice reconstruction thickness, appropriate window/level settings, Results: A total of 775 of 1,000 (77 .5%) patients had one or image reconstruction technique, multiphase assessment for per- more noncoronary findings . A total of 311 of 775 (40 1%). sistence of a defect throughout the cardiac cycle, wall motion patients received one or more recommendations for follow up analysis, and knowledge of common artifact locations . Future imaging and/or clinical correlation . There were a total of 315 directions for novel imaging reconstruction algorithms and possi- diagnostic imaging recommendations; 178 of 315 (56 5%). were ble changes to scan technique will be discussed as well . pulmonary imaging recommendations, including 156 recommen- dations for pulmonary nodules; 68 of 315 (21 .6%) were gas- Conclusion: Perfusion artifacts can complicate the interpretation trointestinal imaging recommendations, including 41 recommen- of perfusion CT scans, and can lead to false-positive identification dations for hepatic lesions and 27 recommendations for esopha- of perfusion defects if not recognized appropriately . Correctly geal thickening or dilatation . Sixty-two of 315 (19 .7%) were car- identifying these artifacts will allow the radiologist to increase diovascular imaging recommendations, including 57 for aortic sensitivity and specificity, and will lead to improvements in scan aneurysm . Seven of 315 (2 .2%) were other imaging recommen- protocols . dations . Twenty follow up imaging studies have been performed to date . Follow up pulmonary imaging includes two of three PET- CT scans positive for primary lung cancer, one chest x-ray for E035. Gender Normalized Reference Values of Heart and pneumothorax, and four CT exams documenting stability of pul- Great Vessel Dimensions in Cardiac CT (CME Credit monary nodules . Follow up cardiovascular imaging includes four Available) CT exams for aortic aneurysm and four transthoracic echocardio- Nevsky, G.; Jacobs, J.; Kim, D.; Chandarana, H.; Donnino, R.; Lim, grams evaluating aortic valvular calcification or left ventricular R.; Srichai, M. New York University School of Medicine, Sunnyside, bulge . Follow up gastrointestinal imaging includes one ultra- NY sound and three MRI studies diagnostic for hepatic cysts and/or Address correspondence to G. Nevsky ([email protected]) hemangiomas . Objective: The objective was to establish gender-normalized Conclusion: At the early stage of this program, determining the ranges of cardiac chamber size, wall thickness, ejection fraction true disease prevalence and clinical significance for our entire (EF) and thoracic aorta and pulmonary artery (PA) diameter on patient population is limited by the small number of follow up electrocardiographic (ECG)-gated cardiac CT angiography (CCTA) . studies . It is clear, however, that the prevalence of noncoronary ancillary findings on coronary artery calcium scoring CT is high . Materials and Methods: Seventy-six consecutive patients [41 The significance of ancillary findings can be substantial in cases females (mean age 52 7. ± 10 3. years) and 36 males (mean age such as a newly diagnosed lung cancer . The prevalence and 41 .2 ± 10 .3 years)] who underwent CCTA on a 64-slice CT sys- diversity of the findings support continued meticulous interpreta- tem between 2005 and 2008, without known history of diabetes, tion by radiologists . hypertension, smoking, or CCTA evidence of structural heart, vas- cular, or coronary artery disease were studied retrospectively . End-systolic left and right atrial size, left ventricular (LV) volumes E034. Analysis of Artifacts in Myocardial Perfusion CT: A and EF was measured using cardiac postprocessing software . Preliminary Experience (CME Credit Available) Thoracic aorta and PA were measured biorthogonally on a 3D Ghoshhajra, B.1; Blankstein, R.1; Rocha-Filho, J.1; Shturman, L.1; workstation . Measurements were normalized to body surface Pien, H.1; Rogers, I.1; Okada, D.1; Brady, T.1; Cury, R.1,2 1. area . Massachusetts General Hospital, Boston, MA; 2. Baptist Cardiac and Vascular Institute, Miami, FL Results: Normalized values for men (values/m2): left atrial size Address correspondence to B. Ghoshhajra (ghoshhajra@gmail. 10 .5 ± 2 .1 cm2; right atrial size 10 .1 ± 1 .7 cm2; LV end-diastolic com) volume 71 .4 ± 15 .6 ml; LV end-systolic volume 23 .8 ± 8 .8 ml; LV EF 67 .5 ± 8%; LV basal wall thickness 4 .2 ± 0 4. mm; LV mid wall Objective: Perfusion CT scanning is a new technique which can thickness 3 5. ± 0 7. mm; LV apex wall thickness 3 2. ± 0 6. mm; allow the detection of myocardial perfusion defects . Several arti- aortic annulus 1 .4 ± 0 .2 cm; aortic sinus 1 .6 ± 0 2. cm; aortic facts cause potential pitfalls for the radiologist . The exhibit will sinotubular junction 1 4. ± 0 2. cm; ascending aorta at level of review and explain artifacts seen when performing myocardial right PA 1 4. ± 0 2. cm; descending aorta at level of left PA 1 1. ± perfusion CT . 0 .1 cm; aorta diaphragm level 1 .0 ± 0 .1 cm; main PA 1 3. ± 0 .1 cm; right PA 1 0. ± 0 .1 cm; left PA 1 .0 ± 0 1. cm . Normalized val- Materials and Methods: Twenty-seven perfusion CT exams ues for women (values/m2): left atrial size 12 .3 ± 2 .1 cm2; right were performed as part of in IRB-approved study . A variety of atrial size 10 .7 ± 1 .7 cm2; LV end-diastolic volume 60 .9 ± 13 .3 scan artifacts have been encountered . These will be demonstrat- ml; LV end-systolic volume 17 .6 ± 6 .7 ml; LV EF 71 ± 8 .1%; LV ed with images, and the underlying CT physics will be explained . basal wall thickness 4 2. ± 0 6. mm; LV mid wall thickness 3 7. ± 0 .6 mm; LV apex wall thickness 3 .1 ± 0 .6 mm; aortic annulus 1 .4 Results: Artifacts will be classified based on the underlying etiol- ± 0 .2 cm; aortic sinus 1 .7 ± 0 .2 cm; aortic sinotubular junction ogy (attenuation/beam hardening-related, motion-related, gating 1 5. ± 0 2. cm; ascending aorta at level of right PA 1 6. ± 0 2. cm; misregistration-related, temporal slab artifacts, and image noise- descending aorta at level of left PA 1 2. ± 0 1. cm; aorta diaphragm related) . Examples will be provided of each . Various processing level 1 1. ± 0 1. cm; main PA 1 4. ± 0 1. cm; right PA 1 1. ± 0 2. cm; techniques to differentiate these artifacts from true perfusion left PA 1 .1 ± 0 2. cm . There were statistically significant differences

187 El e c t r o n i c Ex h i b i t s : Cardiopulmonary between normalized reference values for males and females for E037. Imaging Features of Cardiac Assist Devices left atrial size, LV end-systolic and end-diastolic volumes, aortic Ginat, D.; Bhatt, S.; Singh, M.; Dogra, V. University of Rochester, diameters at all measured levels and left PA diameter . Rochester, NY Address correspondence to D. Ginat ([email protected]) Conclusion: Gender-normalized reference measurements for car- diac chambers, aorta and pulmonary arteries are determined Background Information: The purpose of this exhibit is to with CCTA in subjects free of cardiac risk factors or CCTA- review the types of commercially available cardiac assist devices; detectible cardiac disease . review the physiologic consequences of the cardiac assist devic- es; illustrate the normal imaging appearance of the variety of assist devices, and discuss potential complications associated E036. Transthoracic Echocardiography Provided with these devices . Underestimation of Left Ventricular Outflow Tract Area and Aortic Valve Area Compared to Measured by Planimetry in Educational Goals/Teaching Points: The major teaching points Cardiac CT and Transesophageal Echocardiography of this exhibit are: 1 Various. cardiac assist devices are used in the Puntawangkoon, C.; Entrikin, D.; Ntim, W.; Chen, M.; Johnson, T.; management of heart failure . Therefore, it is important to recog- Carr, J. Wake Forest University, Winston Salem, NC nize the normal configuration and functional implications of Address correspondence to C. Puntawangkoon (jirapa2801@ these devices . 2 . X-ray and CT are well-suited for assessing their yahoo.com) positioning . 3 . Main complications include malpositioning, hem- orrhage and infection . Objective: The objective is to assess the geometry and area of the left ventricular outflow tract (LVOT) in stenotic and nonsten- Key Anatomic/Physiologic Issues and Imaging Findings/ otic aortic valves and to determine the aortic valve area by cardi- Techniques: This exhibit will describe the design and physiologic ac CT (CCT) using a planimetry compared with transthoracic echo impact of the various cardiac assist devices, including intra-aortic (TTE) using continuity equation and transesophageal echo (TEE) balloon pumps and ventricular assist devices; illustrate the nor- using a planimetry . mal appearance of cardiac assist devices, and discuss the poten- tial complications associated with cardiac assist devices and their Materials and Methods: Forty-six patients, ages 20-81 years, imaging features . had CCT and echocardiography (either TTE or TEE) within one week of another . Cardiac CT was performed using a 64-slice Conclusion: The radiologist must be familiar with the normal scanner (GE Healthcare, Waukesha, WI) . Aortic valve area (AVA) imaging appearances of the various types of cardiac assist devic- was assessed by planimetry using TEE in 19 cases (used as refer- es and be able to recognize associated complications . ence standard), using CCT in 46 cases and by continuity equation using TTE in 40 cases . LVOT area was determined by planimetry from CCT and by calculating a circular area using the LVOT diam- E038. Cardiac MDCT in Adult Patients with Congenital Heart eter from the three-chamber view in echocardiography . To quan- Disease: Challenging Protocols and Common Pitfalls tify the deviation from a perfect circle, eccentricity index (EI) was Torres, F.; Nguyen, E.; Doyle, D.; Ayyappan, A.; Abadi, S.; Provost, calculated using the formula: 1-(minor LVOT diameter/major LVOT Y.; Crean, A.; Paul, N. Toronto General Hospital, University of diameter) . Toronto, Toronto, Canada Address correspondence to F. Torres ([email protected]) Results: The LVOT area based on the LVOT diameter derived from three-chamber TTE was significantly underestimated compared to Background Information: Increasing numbers of patients with planimetry by CCT (3 .48 ± 0 .88 cm2 vs . 5 .09 ± 1 .20 cm2, congenital heart disease (CHD) are surviving into adulthood due p<0 .001; mean difference -1 .6 ± 0 .85 cm2 and percent of the to improvements in surgical techniques and clinical care . Several different LVOT area by TTE and CCT=31 ± 13%) . The median EI imaging modalities play a critical role in the diagnosis and follow- was 0 19. (0 01-0. 30),. indicating that half the subjects had at least up of these patients . The introduction of CT units with 64 rows of 19% difference between the major and minor diameters . An detectors, submillimeter and subsecond isotropic imaging has elliptic LVOT morphology has been established by CCT planimetry made cardiac-gated CT an excellent alternative for patients with in most patients, which potentially contributed to AVA underesti- contraindications to MRI . However, the unique anatomy and mation provided by the circular assumption formula via TTE . physiology of CHD patients poses challenges for optimal contrast Planimetric AVA ranged from 0 .9 to 4 .3 cm2 (2 .91 ±1 cm2) by opacification in structures of interest . This review highlights the TEE . AVA calculated by TTE technique was smaller than that fundamental principles governing targeted CT protocols using measured by TEE (p=0 .01) with the mean difference 0 .69 ± 0 94. clinical examples from a spectrum of CHD and illustrates the cm2, whereas AVA by CCT correlated well with TEE planimetry imaging appearances of common pitfalls when the technique is (p=0 13). with good agreement (correlation coefficient, r=0 91;. suboptimal . the mean difference 0 .16 ± 0 .42 cm2) . Educational Goals/Teaching Points: The goals are to identify Conclusion: Calculation of LVOT area from LVOT diameter results subgroups of adult CHD and surgical corrections that benefit in underestimation of LVOT area compared to area measured by from cardiac CT; describe the potential pitfalls and common mis- planimetry from CCT because of an elliptic morphology of LVOT . takes when evaluating these patients with MDCT, and discuss the This ultimately results in underestimation of AVA by continuity modifications to MDCT protocols required to adequately assess equation . each condition .

188 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: Infective endocarditis remains an important clinical Techniques: This exhibit demonstrates the anatomic and hemo- problem associated with significant morbidity and mortality . dynamic aspects of specific common adult congenital heart dis- Recognizing the spectrum of imaging findings of cardiac and ext- eases that require detailed attention when designing MDCT con- racardiac complications of infective endocarditis is important for trast protocols . A variety of conditions including congenital and diagnostic and optimal patient care management . surgical shunts, baffles and conduits that require specialized MDCT contrast protocols designed to assess the pulmonary veins, atrial anatomy and biventricular function will be discussed . E040. Multidetector and Dual Source CT of Congenital Heart Common pitfalls and the resultant imaging appearances will also Disease in Adults (CME Credit Available) be illustrated . Wiant, A.1; Gilkeson, R.1; Nyberg, E.1; Siwik, E.1,2; Zahka, K.1,2 1. University Hospitals–Case Medical Center, Cleveland, OH; 2. Conclusion: The supervising radiologist must be aware of the Rainbow Babies and Children’s Hospital, Cleveland, OH complex anatomy and altered physiology in adult patients with Address correspondence to A. Wiant ([email protected]) CHD to plan the most appropriate MDCT protocol to successfully image these patients . Background Information: Advances in surgical and medical therapies have enabled increasing numbers of children with pre- viously diagnosed and treated congenital heart disease (CHD) E039. Infective Endocarditis: Pathophysiology, Cardiac and survive into adulthood . Additionally, a growing number of Extra-Cardiac Imaging Manifestations (CME Credit patients with significant congenital heart disease are first diag- Available) nosed in adulthood . Multidetector and dual-source CT are emerg- Murillo, H.1; Lane, M.2; Palacio, F. 1; Marmol-Velez, J.1; Nagar, V. ing technologies that have several advantages over multislice CT, 1; Reddick, R.1; Restrepo, C.1 1. University of Texas Health including decreased radiation dose and improvements in ECG Science Center–San Antonio, San Antonio, TX; 2. South Texas gating capabilities . These factors make multidetector and dual- Radiology Imaging Centers, San Antonio, TX source CT an ideal means to detect and characterize known and Address correspondence to H. Murillo (horacio.murillo@gmail. suspected CHD in the adult . com) Educational Goals/Teaching Points: Overarching goals are to Background Information: Infective endocarditis remains an review the technical and clinical aspects of multidetector and important clinical problem associated with high morbidity and dual-source CT imaging; to improve radiologists’ skills in inter- mortality . Common conditions complicated by infective endocar- preting CT studies of adults with known CHD; and to improve the ditis include intravenous drug abuse, degenerative valve disease sensitivity and recognition of CHD in the previously undiagnosed in the elderly, valve replacement and aortic root repair, vascular adult . After having reviewed this educational exhibit, the reader instrumentations, and placement of intracardiac devices and cen- should be able to do the following: understand the principle and tral lines . Transesophageal or transthoracic echocardiography has technique of multidetector and dual-source CT; understand the been instrumental in the imaging of valvular vegetations and the epidemiology, characteristics, and diagnostic challenges associat- identification of structural complications of endocarditis . ed with adults with CHD; and appreciate the spectrum of MDCT However, CT and MRI have become powerful tools for imaging of characteristics of CHD presenting in adulthood . Participants will infective endocarditis even in conditions where metallic, calcific, also be able to recognize important features of the postoperative and graft material are in or around an infectious nidus limiting appearances of lesions in adults with corrected CHD . echocardiographic imaging . Additional CT and MR advantages include 3D anatomic delineation of structures and complications . Key Anatomic/Physiologic Issues and Imaging Findings/ Moreover, extracardiac manifestations of infective endocarditis Techniques: We review the unique features of multidetector and can be imaged simultaneously including thoracic, nervous sys- dual-source CT that make these imaging options optimal for eval- tem, musculoskeletal, and abdominal organs . uating cardiopulmonary complaints and detecting unsuspected CHD in the adult patient . Briefly, we compare these modalities to Educational Goals/Teaching Points: The goals are to review other techniques, e .g . echocardiography and MRI, which have tra- the spectrum of imaging findings of infective endocarditis by CT, ditionally been used to follow adults with CHD . We also review MR, and echocardiography; to better understand the strengths congenital lesions most likely to be encountered in the adult and limitations of various imaging modalities and when use of with known CHD and the patient with unsuspected CHD . one modality is advantageous, and to recognize typical extracar- diac imaging manifestations of infective endocarditis . Conclusion: Multidetector and dual-source CT are evolving tech- nologies that have particular application in the imaging of adults Key Anatomic/Physiologic Issues and Imaging Findings/ with known and previously undiagnosed CHD . Techniques: The image spectrum of cardiac and extracardiac infective endocarditis manifestations, including thoracic, , musculoskeletal, and abdominal organs; diagnostic imag- ing of direct invasion and embolic complications of infective endocarditis and pathologic correlations, and advantages, disad- vantages, and limitations of echocardiography, CT, and MR imag- ing methods will be outlined .

189 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

E041. Don’t Get Lost in LA: An Electrophysiologists Road using prospective EKG gating and 109 consecutive CTCA studies Map to the Left Atrium (CME Credit Available) (62 male, 47 female) mean age 59 years (24-84), mean BMI Seaman, D.; Meyer, C.; Strunk, R.; Attari, M. University of 27 .8 kg/m2 (16 2-51. 5). performed on 64-row MDCT (Toshiba Cincinnati Medical Center, Cincinnati, OH Medical Systems, Tochigi-ken, Japan) from March 1, 2007 to April Address correspondence to D. Seaman (seaman.danielle@gmail. 30, 2007, all using retrospective EKG gating . All patients were com) clinical cardiology referrals for exclusion of native CAD . Patients received oral ± intravenous metoprolol (50-150 mg) to achieve a Background Information: This exhibit will discuss normal and target heart rate (HR) of =65 bpm . The actual HR prior to CTCA variant left atrial anatomy at MDCT with emphasis on relevance on 320 row MDCT determined the phase of the cardiac cycle to the electrophysiology lab . used for image reconstruction as follows: HR (bpm) (phase %- next R wave) <60 (70%-R), 60-65 (60%-R), >65 (40%-R) . The Educational Goals/Teaching Points: The left atrium (LA) is EDE (mSv) for each study was calculated from the dose length divided into four components: the septum, the vestibule, the product (mGy, cm, CT console) and a thorax conversion factor appendage and the venous portion . This exhibit will emphasize (k=0 .017) and presented as mean (range) . the important normal and variant vascular supply . Results: For 320-row MDCT patients mean EDE=8 .9mSv . Key Anatomic/Physiologic Issues and Imaging Findings/ Subgroup analysis: for one heart beat acquisition 157(91 8%). Techniques: The septum provides access to the LA and relevant patients, there were three groups; phase of R-R cycle used vascular and conducting system will be demonstrated . Common (number of patients, %), mean EDE mSv (range mSv): Group septal abnormalities encountered at cardiac CT angiography one, 70%-R (83, 48 .5%), 7 .7 (4 .7-10 5);. Group two, 60%-R (61, include patent foramen ovale, atrial septal defects and septal 35 .7%), 8 .3 ( 5 1-12. .0), and Group three, 40%-R (13, 7 .7%), 9 .3 aneurysms . The vestibule is the thinnest portion of the left atri- (6 .3-12 .7) . There were 14 patients (8 2%). requiring acquisition um; it surrounds the mitral valve orifice and abuts the coronary during =two heart beats, with corresponding mean EDE of 18 4. sinus posteriorly . The potential for perforation is high in this loca- mSv (13 8-. 22 2). . For 64 row MDCT patients mean tion and is critical in the placement of a mitral isthmus line for EDE=24 7mSv. . Sub-group analysis: Group four, in which EKG atrial flutter . Normal and variant appendage anatomy and criteria tube current modulation was used (n=20, 17 .2%), mean for distinguishing atrial thrombus from delayed enhancement will EDE=15 .3 mSv (10 .6-22 .8), and Group five, no EKG current mod- be discussed . Accessory appendages and their importance on the ulation (n= 89, 81 .7%), mean EDE=26 5. mSv (11 .9-38) . effectiveness of atrial roof line ablations will be considered along with a commonly associated left to right atrial muscular bridge Conclusion: Prospectively EKG gated acquisitions on 320-row (the Bachman’s Bundle) . A brief review of pulmonary venous MDCT with a short X-ray exposure in patients with a slow (<60 anatomy and common venous variants will be illustrated . bpm), steady heart rate achieves a reduction in EDE of 69% Common congenital anomalies such as left superior vena cava compared to a retrospective gated EKG acquisition performed on and partial anomalous pulmonary venous return will be reviewed 64-row MDCT . and the potential impact on electrophysiology planning . Left atri- al access, common ablation techniques and deployable mechani- cal devices are discussed in the context of the described anatomy E043. Evaluation of a Specific Variant of the Left Atrial and variants . The important concept of atrial transport will be Appendage on 64-Slice Coronary Computed Tomographic introduced . Angiography Bailey, J.; Warren, P.; Ghosh, S.; Benson, R.; King, M. The Ohio Conclusion: Evaluation of left atrial anatomy by MDCT prior to State University College of Medicine and Public Health, left atrial catheter interventions results in decreased Columbus, OH times and improve clinical outcomes by decreasing complication Address correspondence to M. King ([email protected]) rates when the relevant atrial anatomy is recognized . Objective: The objective was to evaluate the prevalence and morphology of a specific variant of the left atrial appendage E042. Dose Stratification in CT Coronary Angiography: A (LAA) seen on 64-slice coronary computed tomographic angiog- Comparison of 320-Row with 64-Row MDCT (CME Credit raphy (CTA) . Available) Torres, F.; Ray, C.; Ayyappan, A.; Abadi, S.; Doyle, D.; Nguyen, E.; Materials and Methods: Two independent reviewers retrospec- Crean, A.; Menezes, R.; Paul, N. Toronto General Hospital, tively evaluated 200 consecutive coronary CTA performed at our University of Toronto, Toronto, Canada institution from April to September, 2008 for a specific variant of Address correspondence to F. Torres ([email protected]) the LAA . This was defined as a contrast outlined projection off the LAA which curved superior to the left atrium and medially Objective: The purpose of this study is to document the effective toward the aortic root . These were categorized based on the dose equivalent (EDE) for CT coronary angiography (CTCA) per- presence or absence of pectinate muscles . Those with pectinate formed with 320-row and 64-row MDCT in order to provide muscles were further subclassified based on their size . Any appropriate risk stratification and informed patient consent . thrombus within the left atrial appendage was also noted . Differences were resolved by consensus . Materials and Methods: We retrospectively reviewed 171 con- secutive CTCA studies (106 males, 65 females) mean age 58 Results: Seven of 200 cases were nondiagnostic and excluded years (27-83), mean body mass index (BMI) 27 .5 kg/m2(18 .5- from analysis (3 5%). . Of the remaining 193 cases there were 112 58 .6) performed on 320-row MDCT (Toshiba Medical Systems, males and 81 females with a mean age of 51 9. years . Twenty-six Tochigi-ken, Japan) from March 1, 2007 to June 30, 2007, all of 193 cases demonstrated the variant LAA anatomy (13 4%). . Of 190 El e c t r o n i c Ex h i b i t s : Cardiopulmonary the 26 positive cases, eight were devoid of pectinate muscles monary regurgitant fraction are the key CMR measurements to (30 7%). and 18 contained pectinate muscles (69 2%). . Of those obtain . with pectinate muscles; four, eight and six cases were catego- rized as being small, moderate and large (22 .2%, 44 .4% and 33 .3%), respectively . Of the 193 cases analyzed, thrombus was E045. Review of Delayed Enhancement Cardiovascular MR identified in two (1 0%),. of which one was in a LAA variant Imaging of Ischemic and Nonischemic Cardiomyopathies devoid of pectinate muscles . Brown, M.1; Khalaf, O.1; Jeudy, J.2; Legasto, A.1 1. Beth Israel Medical Center-Manhattan, New York, NY; 2. University of Conclusion: To our knowledge this variant of LAA anatomy has Maryland Medical Center, Baltimore, MD not been previously reported in the CT literature . It is important Address correspondence to M. Brown (brownm32003@yahoo. for radiologists to be aware of this variant to avoid misinterpreta- com) tion as a mass or some other pathologic condition, and to under- stand its relationship to the left atrium in case of thrombus for- Background Information: Delayed enhancement cardiovascular mation . MRI (DE-CMRI) plays an important role in the assessment of car- diomyopathy and thus directly influences patient treatment and survival . The purpose of this exhibit is to discuss the underlying E044. Cardiac MR Evaluation of Repaired Tetralogy of Fallot: relationship between hyperenhancement and myocardial patho- Techniques, Findings, and Prognosis physiology and to review the imaging findings on cardiovascular Paes, F.; Thota, S.; Kardon , R.; Ghersin , E.; Siegel, Y.; Fishman, J. MRI in ischemic and several nonischemic cardiomyopathies . University of Miami, Miami, FL Address correspondence to F. Paes ([email protected]) Educational Goals/Teaching Points: There is a significant rela- tionship between hyperenhancement and myocardial pathophys- Background Information: Tetralogy of Fallot is a common form iology which is based on gadolinium molecules in the extracellu- of cyanotic heart disease . Correction in infancy offers good long- lar space . Ischemic and nonischemic cardiomyopathies (includ- term results . However, residual pulmonary regurgitation or steno- ing sarcoid, hypertrophic cardiomyopathy and viral myocardi- sis, or both, is often present after total correction . For patients tis) have typical patterns of hyperenhancement on DE-CMRI and with a dilated right ventricle (RV) caused by significant pulmo- thus allow for etiologic differentiation when the diagnosis is nary valve regurgitation, pulmonary valve replacement (PVR) has uncertain . proved to be beneficial with respect to reverse remodeling of the RV, decrease in QRS duration, and prevention of chronic right Key Anatomic/Physiologic Issues and Imaging Findings/ heart failure . Cardiac magnetic resonance (CMR) allows precise Techniques: Subendocardial or transmural hyperenhancement and reliable volumetric and flow analysis in addition to providing on DE-CMRI is consistent with the presence of coronary artery a 3D geometry of the heart, and has therefore emerged as a disease (CAD) and ischemic cardiomyopathy (ICM) is the most modality of choice in the decision-making process for evaluation likely diagnosis . If the pattern of enhancement is not subendocar- of right ventricular and pulmonary valve pathology and timing of dial, nonischemic cardiomyopathy is likely present and patterns pulmonary valve replacement . of enhancement may be used to differentiate several etiologies .

Educational Goals/Teaching Points: Our educational goals Conclusion: DE-CMRI is a noninvasive imaging modality that include reviewing the indications and protocol for CMR in helps differentiate between various etiologies of cardiomyopathy patients with repaired Tetralogy of Fallot, illustrating common and thus significantly impacts patient management . pathologic changes of the right ventricle and pulmonary valve identified by various CMR techniques, and recognizing its value as a method for preoperative evaluation and follow-up of right E046. Heartbreak Hotel: Pictorial Essay of Myocarditis and ventricular size, function, and pulmonary valve regurgitation in Cardiomyopathy With Echocardiography Correlation (CME those patients . Credit Available) Borso, M.1; Lee, Y.1; Spokoyny, I.1; Sheehan, J.2; Dill, K.2; Carr, J.2 Key Anatomic/Physiologic Issues and Imaging Findings/ 1. University of California-San Diego, San Diego, CA; 2. Techniques: We review the pathophysiology and common cardi- Northwestern, Chicago, IL ac imaging findings of repaired Tetralogy of Fallot patients, with Address correspondence to M. Borso ([email protected]) particular attention to the known complications and prognostic factors . CMR protocols and sequences are described with empha- Background Information: Cardiomyopathies are a heterogene- sis in the advantages and disadvantages of this method com- ous group of diseases with significant morbidity and mortality, pared with echocardiography and CT . A detailed description of which often have an insidious onset . Imaging, especially cardiac pulmonary valve regurgitation and right ventricular pathology is MR, is playing an ever increasing role in the diagnosis of cardio- presented in a case review format demonstrating its unique myopathies . This exhibit will review the classification and imaging imaging findings . findings of a variety of cardiomyopathies through a case based approach, with emphasis on key differential diagnostic points . We Conclusion: CMR using cine and velocity encoded phase con- will discuss the MR sequences commonly employed . Lastly, we trast sequences is an accurate and reproducible method for eval- will compare and contrast MR with echocardiography in the diag- uation of pulmonary valve and right ventricular pathology before nosis of cardiomyopathies . and after intervention in Tetralogy of Fallot . CMR evaluation can identify patients with chronic pulmonary valve regurgitation who Educational Goals/Teaching Points: This exhibit will include: might benefit from early intervention . Corrected RV ejection frac- 1 . Introduction—epidemiology, WHO classification, pathophysiolo- tion, indexed RV end-diastolic and end-systolic volumes, and pul- gy of specific cardiomyopathies; 2 . MR findings of myocarditis 191 El e c t r o n i c Ex h i b i t s : Cardiopulmonary and cardiomyopathy—overview of MR sequences, cellular mecha- Key Anatomic/Physiologic Issues and Imaging Findings/ nisms for enhancement, limitations/benefits of MR; 3 . presenta- Techniques: A number of normal cardiac anatomic variants may tion of cases grouped by WHO classifications . Specific cases be mistaken for neoplastic mass lesions . Correct differentiation is include: idiopathic familial dilated, alcoholic, ischemic, valvular, dependent on good imaging quality and technique as well as amyloid, sarcoid, hemosiderosis, Chagas, peripartal, eosinophillic, physician experience and knowledge of cardiac anatomy and hypertrophic cardiomyopathy, arrhythmogenic right ventricular potential variants . These variants include crista terminalis, eus- displasia, noncompaction, and Tako-tsubo; 4 . algorithm for nar- tachian ridge, chiari network, prominent atrial-ventricular groove rowing a differential diagnosis, 5 . comparison with echocardiog- fat, and normal structures such as the moderator band, trabecu- raphy—comparison/companion echocardiography cases for the lations, and pectinate muscles . Additionally, a number of patho- above cases (when possible), and a review of current literature logic diagnostic entities may masquerade as cardiac masses . comparing echocardiography and MR for diagnosis of cardiomy- Using CT and MR, these pseudomass lesions can be distin- opathy . guished from true on the basis of location, mobility, tissue characteristics and contrast uptake . These entities include Key Anatomic/Physiologic Issues and Imaging Findings/ interatrial septal aneurysm, lipomatous hypertrophy of the intera- Techniques: A review of cardiac anatomy will be implicit in the trial septum, thrombus, pericardial cyst, cardiac pseudoaneurysm exhibit . We will review the pathophysiology of the cardiomyopa- and coronary artery aneurysm . thies listed above and how that relates to the imaging findings . Modalities utilized will include radiographs, MR, and echocardi- Conclusion: Many cardiac anatomic variants and pseudomass ography . We will review the various sequences utilized in cardiac lesions exist that must be distinguished from neoplastic lesions . MR for the evaluation of myocarditis and cardiomyopathy as well Familiarity with their appearance on CT and MR is essential for as the cellular mechanism for enhancement . Additionally we will accurate differentiation from cardiac mass lesions and appropri- compare and contrast MR and echocardiography for the evalua- ate intervention and management . tion of myocarditis and cardiomyopathies .

Conclusion: At the conclusion of the exhibit the viewer should E049. Delayed Enhancement Imaging–Patterns, Pitfalls and accomplish the following: 1 . be familiar with the classification of Pathology–A Pictorial Review (CME Credit Available) cardiomyopathies; 2 . recognize common MR imaging features of Rajiah, P. Cleveland Clinic Foundation, Cleveland, OH myocarditis and cardiomyopathy and understand characteristic Address correspondence to P. Rajiah ([email protected]) findings for specific cardiomyopathies, 3 . be able to compare and contrast MR and echocardiographic findings in cardiomyopathies . Background Information: Delayed enhancement imaging is an integral component the armamentarium of cardiac imagers . K space segmented Inversion recovery images are acquired 15-20 E048. CT and MR Appearances of Cardiac Pseudomasses: minutes after intravenous injection of 0 .2 mmol/kg of gadolin- Imaging Pearls and Pitfalls (CME Credit Available) ium . Magnitude images require selection of optimal inversion Rueff, L.; Srichai, M.; Jacobs, J.; Chandarana, H.; Axel, L.; Kim, D.; time, while phase sensitive reconstruction doesn’t require this, Lim, R. New York University Langone Medical Center, New York, saving time . It is very useful in detection and characterization of NY myocardial infarction . Uptake of contrast in delayed enhance- Address correspondence to L. Rueff ([email protected]) ment is due to expansion of extracellular space in scars and delayed washout . Delayed enhancement is also seen in a wide Background Information: The differential diagnosis for cardiac spectrum of non ischemic abnormalities . mass is broad, including benign and malignant neoplasms along with a variety of normal anatomic variants and pseudomass Educational Goals/Teaching Points: 1) Delayed enhancement lesions . Misdiagnosis can cause significant morbidity or potential- is very useful in assessing presence of viable myocardium in ly mortality if a benign finding is mistaken for a more aggressive ischemic cardiomyopathy 2) Mid myocardial scar in hypertrophic lesion, triggering inappropriate intervention or management . cardiomyopathy is an adverse prognostic indicator . 3) Scar is While echocardiography remains the initial imaging tool for diag- seen in subepicardial location in myocarditis . 4) Diffuse subendo- nosis and assessment of intracardiac lesions, CT and MRI offer cardial to subepicardial enhancement is seen in amyloidosis . the potential for further characterization of true masses and definitive identification of pseudomass lesions . Familiarity with CT Key Anatomic/Physiologic Issues and Imaging Findings/ and MR appearances of normal structures, anatomic/embryologic Techniques: In ischemic cardiomyopathy, subendocardial or variants and pseudomass lesions is essential for differentiation transmural scarring is seen in coronary artery distribution . Extent from cardiac neoplasms, accurate diagnosis and appropriate of scarred myocardium is essential in determining patients suita- management . ble for revascularization . Specific patterns of enhancement are seen in nonischemic cardiomyopathies such as hypertrophic car- Educational Goals/Teaching Points: This exhibit will: 1 . present diomyopathy (patchy, sand like, septal ), dilated cardiomyopathy the relative advantages and disadvantages of CT and MR for car- (mid wall, septal), arrhythmogenic right ventricular dysplasia diac mass and pseudomass evaluation; 2 . discuss technique opti- (right ventricle free wall), sarcoid (patchy, basal septal), amyloid mization for successful differentiation of cardiac masses from (diffuse subendocardial to epicardial) endocardial fibroelastosis pseudomass entities; 3 . present and discuss anatomic and (diffuse subendocardial, noncoronary distribution), Fabry’s dis- embryologic variants that should be differentiated from patholog- ease (mid myocardial, inferolateral wall), noncompaction ic entities, and 4 . present pathologic entities that may masquer- (trabecular recesses) and myocarditis (subepicardial, inferolateral) . ade as mass lesions and discuss their clinical significance and Delayed enhancement is also seen in acute/subacute pericarditis appearance on CT and MR . (pericardial enhancement) postablation (septum in hypertrophic

192 El e c t r o n i c Ex h i b i t s : Cardiopulmonary obstructive cardiomyopathy, left atrium after ablation), postcardi- E051. Left Atrium–A Pictorial Review of Embryology, ac , valvular diseases (fibrosis of valvular apparatus) and Anatomy and Pathology (CME Credit Available) tumors (differentiates from thrombus) . Rajiah, P. Cleveland Clinic Foundation, Cleveland, OH Address correspondence to P. Rajiah ([email protected]) Conclusion: Presence of scar is useful in risk stratification, thera- peutic management and determining prognosis of cardiomyopa- Background Information: The morphological left atrium is the thies . Knowledge of specific pattern of enhancement is essential posterior most chamber in the heart and is formed by the fusion for determining cause of nonischemic cardiomyopathy . Scar is of primitive left auricle and sinus venosus . The left atrium often a substrate for the development of ventricular arrhythmias . receives pulmonary veins and pumps oxygenated into the left ventricle through the mitral valve . There is a wide spectrum of abnormalities affecting the left atrium . Knowledge of the E050. MRI in Common and Uncommon Cardiac Masses– development, anatomy, normal measurements and hemodynam- A Pictorial Review ics is essential for proper diagnosis . MRI and CT plays a pivotal Rajiah, P. Cleveland Clinic Foundation, Cleveland, OH role in evaluation of left atrial abnormalities . Address correspondence to P. Rajiah ([email protected]) Educational Goals/Teaching Points: MRI is very useful in eval- Background Information: MRI is the most important modality uation of all pathologies in the left atrium . Volume rendered in the evaluation of cardiac masses, due to its high spatial resolu- reconstruction is useful in assessment of the left atrial anatomy tion, large field of view, multiplanar imaging capability and inher- and pulmonary venous connections . Delayed enhancement ent contrast between flowing blood and cardiac chambers . imaging is vital in differentiating left atrial thrombus and tumors . Cardiac masses include tumors (benign, primary malignant, sec- In CT, delayed imaging is useful in differentiating slow flow and ondary malignant) and nontumoral masses . MRI helps in charac- thrombus . terization and differentiation from nontumoral masses and ana- tomical variants . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: This review discusses the development, anatomy, Educational Goals/Teaching Points: Cardiac masses include variants and normal measurements (diameter, area, volume) of tumors and nontumoral masses and MRI is essential in differenti- left atrium . MR imaging planes, sequences and protocols for eval- ating these two, which are managed differently . Postcontrast uating left atrium are discussed . Abnormalities in left atrium MRI is useful for delineating the tumor and characterizing tumor which are discussed in this pictorial review include: congenital neovascularity . Most tumors show enhancement in the delayed (situs inversus, situs solitus with dextrocardia, dextro and levo phase, unlike thrombus which does not . Delayed enhancement transposition, cor triatriatum, unroofed coronary sinus, hypoplas- with high inversion time (600 milliseconds) is useful in differenti- tic left heart syndrome, atrial septal defect [ostium primum, ating thrombus (dark) from tumor (bright) . Myxomas are more ostium secundum, sinus venosus]), postsurgical (mustard proce- common in the left atrium and often attached near fossa ovalis . dure, senning procedure, maze procedure, left atrial appendage Lipomatous hypertrophy of interatrial septum spares the fossa closure), postinterventional (pulmonary venous ablation), abnor- ovalis . mal size (large left atrium [LA], giant LA, small LA), vascular (aneurysm, thrombus, slow flow), tumors (myxoma, lipoma, sar- Key Anatomic/Physiologic Issues and Imaging Findings/ coma, metastasis), and infiltrative disorders (amyloidosis) . The Techniques: In evaluation of cardiac masses, MRI is acquired in role of CT in differentiating thrombus and slow flow is also dis- multiple planes and various sequences are used such as – cussed . Volume rendered 3D images are useful in planning for Functional (cine balanced steady state free precession), anatomi- ablation of pulmonary venous ostia . cal (T1/T2/short tau inversion recovery spin echo sequences), myocardial tagging (spatial modulation of magnetization), per- Conclusion: MRI plays an important role in the assessment of fusion imaging and delayed enhancement (usual inversion time left atrial abnormalities . Knowledge of the development, anato- and long inversion time) . Analysis of signal in various spin echo my, pathology and characteristic radiological features are essen- sequences helps in internal characterization of the mass . Cine tial in the diagnosis of abnormalities . MRI is very vital in differen- sequences evaluate mobility, effect on myocardial contraction, tiating tumor from thrombosis . site of implantation and obstruction . Tagging helps in differentiat- ing contracting and noncontracting myocardium . The various masses in the heart are – benign cardiac tumors (myxoma, lipo- E052. Unusual Fistulas in the Cardiovascular System–A ma, fibeoelastoma, fibroma, hemangioma, rhabdomyoma), pri- Pictorial Review mary malignant cardiac tumors (lymphoma, angiosarcoma, rhab- Rajiah, P. Cleveland Clinic Foundation, Cleveland, OH domyosarcoma, mesothelioma and malignant histiocytoma), sec- Address correspondence to P. Rajiah ([email protected]) ondary malignant tumors (hematogeneous metastasis, direct extension from adjacent tumors) nontumoral cardiac masses Background Information: Arteriovenous (AV) fistula is an (thrombus, lipomatous hypertrophy of interatrial septum, valvular abnormal communication between an artery and vein, which vegetations, pericardial cyst, hydatid cyst) . results in shunting of blood from the high-pressure arterial side to the low-pressure venous side . This creates an abnormal low- Conclusion: MRI is very useful in diagnosis, characterization and resistance circuit that steals from the high-resistance normal cap- delineating extent of cardiac masses . A combination of various illary bed, which can cause tissue ischemia . AV fistulas involving sequences in multiple planes is used . MRI is also useful in follow the aorta and coronary arteries are rare and are usually second- up after treatment . ary to surgeries or interventions . CT and MRI play an important role in the diagnosis of these fistulas .

193 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Educational Goals/Teaching Points: Most AV fistulas involving Key Anatomic/Physiologic Issues and Imaging Findings/ aorta and coronary artery are acquired . AV fistulas can cause tis- Techniques: MRI sequences useful in evaluation of pericardium sue ischemia . Coronary artery fistulas often drain into the right are – Cine steady state free precession (SSFP), T1- and side of heart . T2-weighted spin echo/gradient echo, postcontrast delayed enhancement and quantitative flow ( SVC, pulmonary venous Key Anatomic/Physiologic Issues and Imaging Findings/ flow) . Normal pericardium is smooth and low signal intensity, Techniques: The fistulas that we discuss in this review include – measuring up to 2 mm in systole . Features to be assessed in the Coronary artery to coronary sinus fistulas, inadvertent anastomo- pericardium are thickness, contour, focal/diffuse abnormality, sis of a left internal mammary artery (LIMA) graft to anterior enhancement pattern, pericardial motion/tethering, deptal interventricular vein, aorta to right atrial fistula, aorta to inferior bounce, diastolic filling pattern, deformity of ventricles, superior vena cava (IVC) fistula, right coronary to right atrium to superior vena cava (SVC)/inferior vena cava (IVC) size, flow curves in SVC vena cava (SVC) fistula and complex coronary artery fistulas . and pulmonary veins, pleural effusion and chamber sizes . There Fistulas from coronary artery are rare (right coronary artery [RCA]- is a wide spectrum of abnormalities in the pericardium . The vari- 60 %, left coronary artery [LCA]-35%) and could be congenital, ous abnormalities illustrated in this pictorial review include con- traumatic or iatrogenic . It usually drains in right heart chambers genital (pericardial cyst, absence of pericardium); effusion (cir- (RV-(40%), RA –(25%), PA (15–20%), coronary sinus (7%)}, cumferential, focal, simple/complex, mild/moderate/severe, car- which results in a left to right shunt . Small fistulas can be asymp- diac tamponade); hemopericardium; pneumopericardium; peri- tomatic, but large fistulas develop complications like cardiac fail- carditis (acute, chronic, focal); abscess; calcification; tumors ure, myocardial ischemia or infarction, infective endocarditis and (extension of lung cancer, esophageal cancer, metastasis, lym- rupture . In symptomatic patients, fistulas are closed by percuta- phoma, sarcoma), and constriction (diffuse, focal) . neous device closure or by surgical repair . Aorta–IVC fistulas are usually post-traumatic . Aorta–right atrial fistula usually results Conclusion: MRI is very pivotal in the diagnosis of various peri- from an intimal tear near the aortic root, especially in patients cardial abnormalities . Imaging is done in multiple planes with with prior cardiac surgery . The dense pericardial adhesions result- black blood sequences, cine MRI and delayed enhancement . ing from the previous surgery probably contain the free rupture and contribute to the formation of the aorta–right atrial fistula . CT angiography is an excellent method to delineate the location E054. Right Ventricular Involvement in Patients With Acute and extent of the AV fistulas . MRI offers high spatial resolution and Chronic Myocardial Infarction: A Cardiac Magnetic and multiplanar imaging capabilities, which detect even tiny fistu- Resonance Study las . MR angiography is more useful in accurate delineation . Algeri, E.; Francone, M.; Carbone, I.; Vasselli, F.; Cannavale, G.; Iacucci, I.; Catalano, C.; Passariello, R. La Sapienza University of Conclusion: CT and MRI are very useful in determining the type Rome, Rome, Italy and connection of fistulas involving the aorta or coronary arteries . Address correspondence to E. Algeri (emanuela_algeri@yahoo. Careful analysis in multiple planes is required for complete evalu- com) ation of fistulas . Objective: Right ventricular (RV) involvement occurs in about one-half of patients with inferior acute myocardial infarction E053. MRI in Evaluation of Pericardial Lesions–A Pictorial (AMI) and its identification is relevant as it defines a significant Review clinical entity, associated with considerable immediate morbidity Rajiah, P. Cleveland Clinic Foundation, Cleveland, OH and mortality and has a well-delineated set of priorities for its Address correspondence to P. Rajiah ([email protected]) management . Diagnosis of this condition is challenging as it requires a high degree of suspicion based on clinical findings and Background Information: The pericardium is a flask shaped the early recording of the electrocardiogram through right precor- sac, which is lined by an inner visceral layer and outer serous dial leads, as well as elevated right-sided filling pressures; layer . The pericardial sac contains 10-50 ml of fluid is normal echocardiographic assessment of RV also remains technically dif- conditions . It has two sinuses (transverse, oblique) and multiple ficult . Present study sought to assess feasibility of late enhance- recesses . Pericardium has mechanical, membranous and liga- ment (LE) cardiac MR (CMR) to detect RV infarctions and to eval- mentous functions . MRI is the most useful modality which is use- uate its prevalence in a population of pts with acute and chronic ful in assessing the morphology of pericardium and the function- myocardial infarction (MI) . al consequences of pericardial abnormalities . The purpose of this exhibit is to illustrate the MRI appearances of the various pericar- Materials and Methods: Ninety-seven patients with acute dial disease processes . (n=58) or chronic MI (n=31) were retrospectively assessed . All patients previously underwent CMR using a 1 5T. scanner Educational Goals/Teaching Points: MRI is useful in evaluation (Siemens Medical Solutions, Forchheim, Germany); imaging pro- of all pericardial pathologies, including morphological and func- tocol included in all cases steady state free precession (SSFP) tional abnormalities . Delayed enhancement is very useful in cine-MR sequences, turbo spin-echo (TSE) T2-weighted short tau assessing pericardial inflammation and differentiating pericardial inversion recovery (STIR), 1st pass perfusion and LE imaging layers and fluid . Ventricular interdependence, diastolic restraint, acquired after gadobenate dimeglumine administration (Bracco, diastolic septal bounce, conical/ tubular deformity of ventricles Milan, Italy) . Images were analyzed dividing right ventricle into are features of pericardial construction . Pericardial disease is nine segments and assessing presence of LE enhancement for often focal and imaging in multiple planes is essential for diagno- each segment; data were matched with both electrocardiogram sis . Normal thickness pericardium does not rule out constriction . (ECG) and transthoracic echo which were previously recorded in all patients .

194 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Results: Among our study population, 31/97 patients had inferi- Educational Goals/Teaching Points: MRI is the best modality or MI, 62/97 had anterior wall MI and the remaining four had in evaluation of HOCM . MRI is accurate in assessing the septal extensive chronic scarring involving both anterior and inferolater- thickness . Systolic anterior motion of mitral valve (SAM) can be al walls . Overall, RV LE was observed in 22/97 cases (22%): seen . In-plane phase contrast flow imaging is useful for assessing 13/31 (41%) inferior MI; 9/62 (14%) anterior MIs . In the sub- the flow gradient in left ventricular outflow tract . Delayed group of inferior MI, ECG with right precordial leads + echocardi- enhancement indicates presence of scar, which has adverse prog- ography showed signs of RV involvement in 12/22 cases (54%); nostic significant and requires an implantable cardioverter defi- no hints of RV involvement were observed in the anterior MI pts . brillator . Abnormal papillary muscle morphology is assessed with Additionally, RV infarctions showed larger RV EDV volumes as 3D sequences . In apical hypertrophic cardiomyopathy, a spade compared to others (163 ± 27 mL vs . 132 ± 11 mL p=0 37). . like configuration of distal cavity is noted .

Conclusion: Detection of RV is feasible with LE CMR and very Key Anatomic/Physiologic Issues and Imaging Findings/ often misdiagnosed with conventional clinical-instrumental data . Techniques: MRI sequences used in evaluation of HOCM are cine steady state free precession (functional abnormalities, systol- ic anterior motion of mitral valve .), myocardial tagging (abnor- E055. Cardiac MR Imaging: A Concise Review of Basic malities in contraction and strain), spin echo sequences (for Anatomy, Imaging Planes, and Pulse Sequences (CME edema and differentiating from other lesions), phase contrast Credit Available) flow imaging (gradient across the high velocity jets, flow patterns Vyas, R.; Tuttle, D.; Ginat, D. University of Rochester, Rochester, NY in superior vena cava, inferior vena cava), 3D navigator gated Address correspondence to D. Tuttle ([email protected]. whole heart imaging (anatomy of papillary muscles, apical dis- edu) placement of anterolateral papillary muscle and bifid posterior muscle are abnormal) and delayed enhancement (presence of Background Information: Cardiac MR imaging can be challeng- scar is confined to hypertrophied areas, is a substrate for arrhyth- ing for the resident and novice radiologist . The purpose of this mia and indicates adverse prognosis) . MRI is useful in classifying exhibit is to discuss the cardiac pulse sequences, familiarize the the hypertrophic cardiomyopathy (concentric, eccentric, basal, viewer with the standard cardiac MR imaging planes, and provide mid ventricular, apical, Takusubo) . Delayed enhancement is con- an interactive review of basic cardiac MR anatomy . fined to hypertrophied area and is due to myofibrillar disarray and expansion of interstitial space or due to presence of Educational Goals/Teaching Points: The standard cardiac pulse ischemia . sequences for cardiac morphology, function, perfusion, and via- bility assessment will be demonstrated . Standard imaging planes Conclusion: MRI is a very useful modality in evaluation of hyper- of the heart, great vessels, and coronary arteries will be shown . trophic cardiomyopathy . MRI is used in diagnosis, determining Basic cardiac anatomy will be reviewed and presented in an the type, evaluation of function, estimating flow gradient and interactive quiz format . most importantly for presence of scar .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: An interactive format integrating cardiac anato- E057. Brain Natriuretic Peptide’s Emerging Supplemental my on MRI in standard imaging planes will be presented . Role in Improving the Diagnosis of Congestive Heart Failure in Conjunction with (CME Credit Conclusion: After the exhibit the viewer will be familiar with Available) basic cardiac MR imaging sequences; understand cardiac imaging Di Poce, J.; Salvatore, M.; Geha, F.; Abi Rafeh, N.; Ahern, K. Staten planes, identify basic cardiac anatomy on MR . Island University Hospital, Staten Island, NY Address correspondence to J. DiPoce ([email protected])

E056. Role of MRI in Evaluation of Hypertrophic Objective: The objective was to evaluate the supplemental role Cardiomyopathy–A Pictorial Review (CME Credit Available) of brain natriuretic peptide (BNP) in improving diagnosis of con- Rajiah, P. Cleveland Clinic Foundation, Cleveland, OH gestive heart failure (CHF) utilizing chest radiographs . Address correspondence to P. Rajiah ([email protected]) Materials and Methods: Institutional review board approval, Background Information: Hypertrophic cardiomyopathy is an HIPPAA compliance and informed consent were obtained . A total inherited disorder characterized by inappropriate myocardial of 355 patients (172 females and 183 males, average age 70 .9 hypertrophy in the absence of obvious cause of hypertrophy such years old, range 28-102) were included if their emergency depart- as systemic hypertension or aortic stenosis . It is the most com- ment chief complaint was dyspnea . Participants were over 18 mon cause of sudden death in young patients . Pathologically it is years old and not pregnant . Patients were not included if their dys- characterized by myofibrillar disarray and endothelial dysfunction . pnea was clearly not related to pulmonary edema such as from The various types are concentric, eccentric, basal, mid ventricular, pneumothorax . A research assistant documented the BNP value . apical (Yamaguchi) and Takotsubo . It may also involve the right The radiograph was then interpreted by a board certified radiolo- ventricle and can be associated with atrial dilation . MRI is a very gist without other patient knowledge, including lab data and/or important tool in the diagnosis and characterization of hyper- preliminary diagnosis . Radiographs were evaluated for presence trophic obstructive cardiomyopathy (HOCM) . The purpose of this and severity of CHF . After at least one week passed, the same radi- exhibit is to illustrate the typical MRI findings and variants in ographs were reviewed by the same radiologist with BNP . Two HOCM . separate clinicians reviewed the history, physical exam, diagnostic tests and laboratory data to establish the final diagnosis .

195 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Results: Sensitivity increased from 82 6%. without BNP to 94 5%. E059. MDCT in the Preoperative Evaluation and Surveillance with BNP significant at p .02, Chi Square, Yates corrected . ANOVA of Endovascular Repair of the Thoracic Aorta showed that BNP levels for radiograph diagnoses of negative, Godoy, M.; Cayne, N.; Ko, J. New York University, New York, NY mild, moderate and severe CHF were significantly different at Address correspondence to M. Godoy ([email protected]) p .000 . Tukey-Kramer Multiple Comparison test indicated that the BNP levels were significantly lower in the negative or mild group Background Information: Endovascular techniques have recent- compared to the moderate or severe group . ROC curves showed ly emerged as a less invasive alternative for repair of descending that AUC for radiograph diagnosis with BNP was 0 .784 and with- thoracic aortic pathology (aneurysm, pseudoaneurysm, aortic dis- out BNP was 0 669. . This difference was 0 .114, Z value 3 .94 and section, penetrating aortic ulcer, intramural hematoma and trau- p=0 .0001 . matic aortic rupture) . The purpose of this educational exhibit is to discuss and illustrate the role of MDCT and CT reformations in Conclusion: CHF diagnosis with chest radiograph significantly the preoperative assessment of the aorta and postendograft fol- improved with the addition of BNP . Additionally, BNP values are low up . significantly different between chest radiograph severity groups . BNP should be available to radiologists when evaluating the Educational Goals/Teaching Points: MDCT protocol for assess- chest radiographs of patients short of breath because BNP ing the pre- and postsurgical aorta will be addressed along with improves congestive heart failure diagnosis . inclusion criteria for endovascular repair of the thoracic aorta (TEVAR) . The postoperative appearance after TEVAR will be reviewed with emphasis placed on complications, including E058. Volume Visualization of Isotropic CT Data: Role in endoleak (Types I to IV), endotension; graft kinking, migration, Imaging the Ascending Aorta (CME Credit Available) and infection; embolism; iatrogenic aortic dissection or rupture . Johnson, P.; Horton, K.; Fishman, E. Johns Hopkins University School of Medicine, Baltimore, MD Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to P. Johnson ([email protected]) Techniques: Noncontrast CT prior to contrast-enhanced CT imag- ing enables easier identification of acute intramural hematoma, Background Information: Contrast-enhanced CT is the primary aortic calcification and differentiation of pre contrast high attenu- imaging modality used for suspected aortic pathology . In the past ation areas from areas that enhance on post contrast imaging decade, dataset quality has been improved by both advances in (endoleaks) . Preoperative CT evaluation requires precise charac- scanner technology and display techniques . Because of the ana- terization of pathology using post-processing techniques such as tomic configuration of the ascending aorta, characterization of curved multiplanar reconstructions . Important information to be pathology is facilitated by interactive multiplanar display of a contained in the radiology report includes: measures of the maxi- high-resolution dataset acquired during maximum enhancement . mal true cross-sectional diameters of the aorta at and immedi- ately proximal, and distal to the pathological segment(s); pres- Educational Goals/Teaching Points: This exhibit will discuss ence of excessive angulation of the aortic arch; and distance of protocol optimization for 64-MDCT of the thoracic aorta and the the proximal and distal aspects of the aortic pathology from ana- utility of interactive multiplanar display for this anatomic region . tomical landmarks such as the left subclavian artery and celiac It will demonstrate the CT appearance of a range of pathology artery, respectively . Circumferential thrombus, calcification at the that affects this section of the thoracic aorta . planned endograft landing zones, aortic, femoral, and/or iliac artery tortuosity may affect candidacy for endograft therapy . 3D Key Anatomic/Physiologic Issues and Imaging Findings/ volume rendered techniques readily enable assessment of the Techniques: The exhibit will include protocol optimization (iso- position and integrity of the stent graft . MPRs play a major role in tropic data acquisition, contrast infusion technique and timing, the identification and characterization of endoleaks, change in the importance of cardiac gating); postprocessing and display size of the aorta, or other complications . (2D multiplanar reconstructions, 3D maximum intensity and vol- ume rendering), and pathology of the ascending aorta (aortic Conclusion: MDCT with reformations serve an important role in valve disease, supravalvular aortic stenosis, aneurysm, pseudoan- the preoperative and postoperative evaluation of the thoracic eurysm, dissection, penetrating ulcer, intramural hematoma, and aorta . Familiarity with the criteria used for determining the candi- concomitant coronary artery disease) . dacy or exclusion of patients for TEVAR is essential . An under- standing of the normal appearance of the postoperative thoracic Conclusion: Pathology that affects the ascending aorta must be aorta enables identification and timely treatment of potentially evaluated in conjunction with assessment of the aortic valve, as fatal complications . well as the coronary arteries since many of these patients are managed surgically . As shown by the cases presented in this exhibit, MDCT interpretation is optimized by attention to acquisi- tion technique, including cardiac gating, and the use of interac- tive multiplanar display techniques .

196 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

E060. Thoracic-Vascular Anomalies: Recognition on CT Imaging Conclusion: Radiologists should be familiar with the MDCT Kakarla, R.; Weiss, J.; Kirshenbaum, K. Illinois Masonic Medical appearances and clinical importance of these rare venous disor- Center, Chicago, IL ders of the thorax . Address correspondence to R. Kakarla ([email protected])

Background Information: Advances in MDCT technology have E062. Back to Basics: The Language of Signs in Thoracic allowed for accurate visualization of thoracic vasculature and rare Radiology associated anomalies . MDCT and CT angiography (CTA) tech- Choi, E.1; Patel, M.2; Batra, P.3; Verma, R.2; Jude, C.2 1. University niques allow for accurate depiction of such anomalies and obvi- of California-Los Angeles Medical Center, Los Angeles, CA; 2. ate need for conventional angiography for their visualization . As Olive View – University of California-Los Angeles Medical Center, thoracic vascular anomalies have significant clinical implications, Los Angeles, CA; 3. West Los Angeles Veterans Affairs Medical especially in the pediatric population, it is essential to be aware Center, Los Angeles, CA of their presentation of cross-sectional imaging . Address correspondence to C. Jude ([email protected])

Educational Goals/Teaching Points: The goals are to review Background Information: The purpose of this educational various thoracic vascular anomalies recognized on CT imaging; exhibit is to review the classic radiological signs in thoracic imag- emphasize proper recognition of thoracic vascular variants in ing on chest radiographs and CT based on anatomic loca- order to avoid misdiagnosis of pathology and facilitate proper tion . Recognition of these signs in thoracic imaging is important intervention, and delineate the clinical implications of each of the for describing abnormalities, understanding pathological process- thoracic vascular variants commonly encountered . es and formulating a differential diagnosis .

Key Anatomic/Physiologic Issues and Imaging Findings/ Educational Goals/Teaching Points: The educational goals of Techniques: Thoracic vascular variants encountered on our this exhibit are to review the definition of classic signs in thoracic review include: left sided superior vena cava, partial anomalous radiology; to illustrate these signs by examples on chest radio- pulmonary venous return, azygous vein fissure, anomalous left graphs and CT, and to describe the significance and limitation of brachiocephalic vein, left sided aortic arch with aberrant right each sign . subclavian artery, right sided aortic arch with aberrant left subcla- vian artery, scimitar syndrome, arteriovenous malformations, and Key Anatomic/Physiologic Issues and Imaging Findings/ left pulmonary artery sling . There will be a discussion of other Techniques: The proposed exhibit will be organized based on vascular anomalies and their clinical implications . the location of the radiological signs . The following signs will be discussed: Parenchyma and Airways -air bronchogram, silhouette, Conclusion: Anomalies of intrathoracic vessels can alter radio- air crescent, gloved finger, Golden S, Luftsichel, flat waist, fallen graphic anatomy of the mediastinum . CT is an excellent tool in lung, CT angiogram, halo, signet-ring, tree-in-bud, comet tail; illustrating the variant thoracic vascular anatomy . It is essential to Mediastinum and Hila-cervicothoracic, hilum convergence or recognize these entities in order to avoid misdiagnosis of pathol- overlay, doughnut, continuous diaphragm, ring around the artery, ogy and assist in proper intervention if necessary . double density, fat pad; Vascular-Fleischner, Hampton’s hump, Westermark, figure 3, scimitar; and Pleura and Chest Wall-deep sulcus, tapered margins, split pleura . E061. Unusual Thoracic Venous Abnormalities: Appearance on MDCT (CME Credit Available) Conclusion: At the end of reviewing this exhibit, readers will be Hendi, J.; Maldjian, P. University of Medicine and Dentistry of New able to recognize the common signs in thoracic radiology; relate Jersey-New Jersey Medical School, Montvale, NJ the signs to anatomical structures and pathological processes, Address correspondence to J. Hendi ([email protected]) and understand the significance and limitations of each sign .

Background Information: Radiologists are confronted by unan- ticipated venous abnormalities of the thorax during interpretation E063. Chest Imaging in the Intensive Care Unit: Evaluation of CT studies . Correct diagnosis of these disorders may affect of Tubes, Lines, Catheters and Monitors (CME Credit patient management and avoid further unnecessary imaging . The Available) purpose of this exhibit is to demonstrate the MDCT appearance Godoy, M.; Leitman, B.; Vlahos, I.; deGroot, P.; Naidich, D. New of some of the more unusual thoracic venous abnormalities . York University, New York, NY Address correspondence to M. Godoy ([email protected]) Educational Goals/Teaching Points: Some of the rare venous abnormalities discussed in this exhibit include: pulmonary vein Background Information: The evaluation of portable chest radio- varix, retroaortic left subclavian vein, atypical venous drainage of graphs of patients in the intensive care unit is a challenging task pulmonary sequestration, “escape” of the azygos vein from the due to technical limitations as well as the inability of patients to azygos fissure, uncommon variants of partial anomalous pulmo- cooperate . However, it is essential to evaluate the multiple support nary venous return (before and after surgical repair) and systemic and monitoring devices used in these patients . As a component of venous to pulmonary venous shunt . accurate interpretation of portable chest radiographs, it is neces- sary to stay abreast of newer devices and potential complications . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: We emphasize the vital role of multiplanar image Educational Goals/Teaching Points: In this educational exhibit reformatting and volume rendering in distinguishing among we discuss and illustrate normal and aberrant positioning of these anomalies and making the correct diagnosis . support and monitoring devices, as well as their inherent complications . 197 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Key Anatomic/Physiologic Issues and Imaging Findings/ E065. Potential Clinical Applications of Dual-Energy CT in Techniques: The support and monitoring devices illustrated in Thoracic Imaging (CME Credit Available) this exhibit include endotracheal and tracheostomy tubes, Godoy, M .1; Naidich, D .1; Leidecker, C .2; Assadourian, B .1; nasogastric/feeding tubes, central venous and Swan-Ganz cathe- Schmidt, B .2; Vlahos, I .1 1. New York University, New York, NY; 2. ters, intra-aortic counter-pulsation balloon pumps, thoracic Siemens Medical Solutions, Malvern, PA drains, cardiac pacemakers/automatic implantable cardioverter Address correspondence to M . Godoy (migbarco@gmail com). defibrillators, as well as an assortment of other less commonly used devices . Background Information: Recent advances in dual-source MDCT technology have allowed simultaneous acquisition of CT Conclusion: The recognition of complications arising from the images at two different tube voltage settings during a single introduction and use of these devices is often not clinically acquisition . The advantages of dual-energy CT (DECT) technique apparent; therefore radiologists are critical in the detection and are twofold . Low kilovoltage imaging in CT angiographic studies confirmation of these issues . results in increased iodine conspicuity, due to increased photoe- lectric interactions . The use of simultaneously acquired low and high kVp data permits the calculation of material specific images E064. Imaging Manifestations of Chest Lesions in Patients based on the differential CT attenuation of selected substances at with HIV/AIDS (CME Credit Available) two different energies . The purpose of this educational exhibit is Ferguson, E.1; Berkowitz, E.2 1. The University of Texas Medical to review and illustrate potential clinical applications of DECT for School at Houston, Houston, TX; 2. Emory University School of thoracic imaging . Medicine, Atlanta, GA Address correspondence to E. Ferguson (ecferguson@hotmail. Educational Goals/Teaching Points: The potential clinical com) applications of DECT for thoracic imaging include evaluation of the thoracic aorta, pulmonary arteries, pulmonary nodules and Background Information: Many abnormalities are encountered masses, nodes, pleural disease and airway disease . on chest radiographs and computed tomographic images of patients with HIV/AIDS . Distinguishing among these various enti- Key Anatomic/Physiologic Issues and Imaging Findings/ ties and rendering appropriate differential diagnoses is crucial for Techniques: The increased conspicuity of iodine at low tube directing patient care . Examples include opportunistic infections voltage images improves vascular opacification at CT angiography such as fungal, mycobacterial, Pneumocystis jiroveci and other of the aorta or pulmonary arteries . Consequently, the number of atypical pneumonias, malignancies such as lymphoma and inconclusive pulmonary artery studies may be reduced . In aortic Kaposi sarcoma, lymphoid interstitial pneumonia, as well as imaging, material specific DECT imaging has the potential to other abnormalities such as and adenopathy in eliminate the necessity to perform precontrast images by the use certain settings . Each type of abnormality, its imaging appear- of virtual noncontrast images . Material specific pulmonary blood ance, and distinguishing features will be reviewed . flow maps allow for detection of iodine perfusion defects in the pulmonary parenchyma in patients with pulmonary emboli . For Educational Goals/Teaching Points: The exhibit viewer will pulmonary nodules, masses, pleural disease and nodes DECT can review the many intrathoracic imaging abnormalities encoun- be used for the detection of calcification and enhancement on tered in patients with HIV/AIDS; learn to distinguish and render postcontrast studies alone by depicting the presence of calcium appropriate differential diagnoses of pulmonary and other and iodine, respectively . Characterization of large and small air- intrathoracic lesions associated with HIV/AIDS, and understand ways disease may be improved by the use of DECT subtraction the importance of each abnormality, its pathophysiology, and techniques comparable to ventilation/perfusion imaging . DECT treatment, as well as prognosis . identification and removal of osseous structures is another appli- cation, which is particularly useful for 3D imaging and significant- Key Anatomic/Physiologic Issues and Imaging Findings/ ly reduces postprocessing time . Techniques: The radiographic manifestations, pathophysiology, and clinical outcome of each type of intrathoracic abnormality Conclusion: Dual-source DECT is a new technique with a variety associated with HIV/AIDS will be explained . The importance of of potential clinical applications for thoracic imaging . distinguishing among these lesions will be discussed, especially since many of these lesions are treated differently and have dif- ferent clinical implications . E066. Road Rules: Evaluation of Lesions in the Thoracic Inlet (CME Credit Available) Conclusion: Many chest imaging abnormalities associated with Covarrubias, D.1; Surapaneni, K.1; Reede, D.1; Smoker, W.2; HIV/AIDS are first diagnosed radiologically, making it crucial to Holliday, R.3; Gentry, L.4 1. Long Island College Hospital, distinguish among these various abnormalities in order to opti- Brooklyn, NY; 2. University of Iowa Hospitals and Clinics, Iowa mize patient care . This exhibit will serve to review the diverse City, IA; 3. The New York Eye and Ear Infirmary, New York, NY; 4. imaging lesions found in the lungs and other parts of the chest University of Wisconsin Hospitals, Madison, WI in patients with HIV/AIDS, to render diagnostic clues that aid in Address correspondence to D. Covarrubias (dcovarru@chpnet. distinguishing among these various diseases, and to explain the org) pathophysiology and prognosis of each disease . Understanding these diseases, their imaging manifestations, and clinical rele- Background Information: The purpose of this computer-based vance will improve patient outcome . exhibit is to review the anatomy of the thoracic inlet (TI); review the clinical and radiographic findings of lesions encountered in this region .; illustrate common pathways of disease spread, and

198 El e c t r o n i c Ex h i b i t s : Cardiopulmonary demonstrate a systematic approach for the interpretation of Conclusion: Upon completion of this exhibit the viewer will have cross-sectional images of the TI . become familiarized with common and uncommon thoracic radi- ographic manifestations of sarcoidosis; learned what CT imaging Educational Goals/Teaching Points: The exhibit viewer will findings to look for that can help identify or exclude sarcoidosis learn the anatomy of the TI; develop an understanding of the when faced with a challenging case, and have the ability to offer anatomic spaces that cross the TI (carotid, visceral, danger, and a more focused differential diagnosis when appropriate . perivertebral); learn pathology encountered in this region with an emphasis on the space of origin, and be able to demonstrate a systematic approach for the evaluation of lesions in the TI based E068. A Radiologist’s Guide to the Revised Staging System on the space and/or organ of origin . for Nonsmall Cell Lung Cancer (CME Credit Available) Kligerman, S.; Abbott, G.; Fidias, P.; Neal, J. Massachusetts Key Anatomic/Physiologic Issues and Imaging Findings/ General Hospital, Boston, MA Techniques: Lesions in the various anatomic spaces of the neck Address correspondence to S. Kligerman (skligerman@partners. will be illustrated, including the following: 1) Carotid Space: org) carotid and jugular venous thrombosis, aortic dissection with extension into the carotid artery; 2) Visceral Space: thyroid Background Information: On January 1, 2009, the American lesions, esophageal lesions, infection, and central airway patholo- Joint Committee on Cancer (AJCC) will adopt a revised TNM stag- gy (i .e ., tracheal stenosis, saber-sheath trachea, tracheoceles, and ing system for nonsmall cell lung cancer as proposed by the Mounier-Kuhn syndrome); 3) Retropharyngeal Space: infection; International Association for the Study of Lung Cancer (IASLC) . 4) Perivertebral Space: location and pathology affecting major This new staging system will alter management and treatment in nerves (recurrent laryngeal, phrenic, sympathetic chain, cervical many patients diagnosed with nonsmall cell lung cancer . nerve roots and brachial plexus) . Educational Goals/Teaching Points: The goal of this education- Conclusion: The TI is a busy intersection between the neck and al exhibit is to describe and illustrate the new staging revisions the chest, containing a number of structures from several organ using a series of graphic illustrations and case-based examples . systems . An understanding of the pertinent anatomy and pathol- Additionally, the exhibit will explain the rationale behind these ogy that involves this region is essential for accurate interpreta- revisions so the radiologist can better understand their clinical tion of radiologic studies . This exhibit presents this anatomic and implications . pathologic information in an organized, algorithmic fashion in order to allow the viewer to develop a systematic approach for Key Anatomic/Physiologic Issues and Imaging Findings/ the interpretation of these studies . Techniques: Some important changes to the TNM classification of nonsmall cell lung cancer include the subdivision of the T1 and T2 cancers based on the size of the tumor . Satellite lesions E067. Will the Real Sarcoid Please Stand Up: How to in the same lobe, once staged as T4, and in a different lobe, Differentiate Sarcoidosis from Common Mimics Seen in once staged as M1, will now be considered T3 and T4 lesions, Thoracic Imaging respectively . The M staging system will also be subdivided into Flamini, D.; Song, Y.; Covarrubias, D.; Martino, J.; Leonardo, R.; M1a and M1b, where M1a disease represents nodules in the Reede, D. Long Island College Hospital, Brooklyn, NY contralateral lung and M1b disease represents distant metastatic Address correspondence to D. Flamini ([email protected]) disease . Malignant pleural effusions or pleural nodules will now be classified as M1a disease instead of T4 . Background Information: Sarcoidosis can be perplexing to resi- dents and practicing radiologists who may be asked to interpret Conclusion: Given the multiple changes to the TNM staging sys- cases on call or as part of their general coverage . Given that there tem for nonsmall cell lung cancer, it is integral that radiologists is overlap in the radiographic appearance of many disease enti- learn the revised staging system and understand the reasons for ties in the lung, we propose a method of review that directly com- the changes so that we can continue to provide the best care for pares cases of sarcoid with other disease entities that may have the patient . similar appearances, in order to emphasize the correct findings .

Educational Goals/Teaching Points: The goals are to increase E069. Screen Detected Lung Cancer – Retrospective Analysis the general radiologist’s ability to make a confident diagnosis in of CT Appearance (CME Credit Available) straightforward and more atypical cases of sarcoidosis, and to Dhopeshwarkar, M.; Menezes, R.; Dong, Z.; Sitartchouk, I.; emphasize the distinguishing characteristics of sarcoid from simi- Keshavjee, S.; Boerner, S. University Health Network, Toronto, lar appearing, but different disease entities . Canada Address correspondence to M. Dhopeshwarkar (monikad- Key Anatomic/Physiologic Issues and Imaging Findings/ [email protected]) Techniques: The exhibit will review typical imaging findings of sarcoidosis at various stages of appearance and present case Objective: The objective was to retrospectively evaluate charac- pairs of sarcoid with a closely matched nonsarcoid mimic accom- teristics of cancers diagnosed in a low dose CT lung cancer panied by a discussion of the salient imaging features for distinc- screening study . tion . Both typical and atypical appearances will be included . Cases will be presented as unknowns to allow the participant to Materials and Methods: As part of I-ELCAP we screened a test themselves . cohort of 4,738 at risk current and former smokers, 2,601 (55%) women and 2,137 (45%) men . Seventy-seven cancers in 75 indi-

199 El e c t r o n i c Ex h i b i t s : Cardiopulmonary viduals were detected and evaluated for time point of detection, underlying pathological features, and understand the role of location, morphology, histology, stage at diagnosis, treatment and chest radiographs and updated CT and other imaging modalities survival . In 37 cases PET was available for correlation . Follow-up in making the correct diagnosis . imaging for computation of growth rates was available in 57 cases . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The pathologies presented are atypical adenoma- Results: Seventy-seven cancers were found in 74 individuals, 56 tous hyperplasia, focal fibrosis, nodular lymphoid hyperplasia, women and 19 men, ranging in age from 50-79 years (mean 63 malignant lymphoma, inflammatory myofibroblastic tumor, years) . Only five (6 .5%) cancers were not seen on baseline scan . tumorlet, pulmonary amyloidosis, round atelectasis, focal organiz- Histology revealed 56 (73%) adenocarcinoma, 11 (14%) squa- ing pneumonia, intrapulmonary lymph node, tuberculoma, cryp- mous cell cancer (SCC), five (6%) small cell lung cancer (SCLC), tococcosis, Wegener’s granulomatosis, parasitic infection, foreign two (3%) large cell carcinoma and three (4%) carcinoid . The body granuloma in the peripheral lung, sarcoidosis, actinomyco- most common location was left upper lobe (34%) and right sis, invasive aspergillosis, and other types of miscellaneous infec- upper lobe (31%) . Forty-four cancers were solid (57%), 14 (18%) tious disease and granulomas . nonsolid and 19 (25%) part solid . Thirty-two (40%) lung cancers had spiculations and 54 (70%) irregular margins . Mean tumor Conclusion: Awareness of miscellaneous pulmonary conditions size was 17 x 13 mm . Fifty-three (69%) cancers were Stage I (IA that produce radiological findings that mimic lung cancers with 51%, IB 18%) . Most of the cancers (n=57, 74%) were treated an understanding of their pathological background and careful surgically . To date 65 patients are alive, with a median observa- attention to the clinical information will help in achieving correct tion time of 26 months, survival is 87% . Only nine cases were diagnoses . central masses: two extensive stage SCLC, one large cell (3A) and three SCC (stage 4, 3B and 1B each) one stage 4 adenocarcino- ma and two stage 1A carcinoid, all others were peripheral . Of 37 E071. CT Staging of Lung Cancer: The Role of 3D Imaging cancers evaluated by PET scan, 20 (54%) were metabolically (CME Credit Available) active: all of the squamous, SCLC and large cell cancers but only Park, K.; Sun, J. Ajou University, Suwon, South Korea 12 (48%) of the adenocarcinoma were active . Of the 57 cases Address correspondence to K. Park ([email protected]) with follow up CT scans, 34 nodules increased in size . Mean dou- bling time (DT) for all cancers was 232 days (median 113) . In 26 Background Information: MDCT maximizes the advantages of women, mean DT was 239 days (median 131), while in eight multiplanar reformat (MPR) and 3D volumetric images providing males, mean was 110 days (median 87) . DT of >400 days was useful information for staging in lung cancer . The purpose of this present in five cases, all women and all adenocarcinoma . The exhibit is to explain optimal CT techniques and reconstruction mean and median DT for adenocarcinoma was 237 and 123 days methods, and to discuss the advantages and pitfalls of 3D imag- respectively, for SCLC 136 and 148 days respectively and for SCC ing in CT staging of patients with lung cancer . 73 and 63 days, respectively . Educational Goals/Teaching Points: The goals of this exhibit Conclusion: Screening detects lung cancer in an early treatable are to learn optimal imaging techniques and reconstruction stage . Central tumors are less common in screen-detected can- methods for CT imaging of patients with lung cancer; to under- cers and more often detected at late stage . Women have a higher stand advantages and pitfalls of MPR, 3D, virtual bronchoscopy, prevalence of lung cancers and have more slow-growing adeno- and angioscopy for T-staging of lung cancer related with airway, carcinoma . Most cancers can be surgically resected and survival is mediastinal vessels, fissure and chest wall, and to recognize pos- high after a medium observation time of 26 months . sible application of MPR imaging for N- and M- staging of lung cancer .

E070. Mimickers of Lung Cancers, Spectrum of CT Findings Key Anatomic/Physiologic Issues and Imaging Findings/ with Pathological Correlation (CME Credit Available) Techniques: The use of a narrow detector collimation and over- Furuya, K.1; Yaumori, K.1; Sakino, I.2; Takeo, S.1; Sakai, M.1; lapping reconstruction intervals is mandatory for a high z-axis res- Uesugi, N.1; Kiyohisa, H.1; Seiya, M.1; Muranaka, T.1 1. National olution in MDCT imaging . MPR and 3D volume-rendering images Hospital Organization Kyushu Medical Center, Fukuoka, Japan; 2. are useful for staging of airway and vascular involvement . Virtual Saiseikai Yahata General Hospital, Kitakyushu-City, Japan bronchoscopy and angioscopy have a limited value, but are Address correspondence to K. Furuya ([email protected]) potentially useful for a group of particular cases . MPR images are accurate for the detection of transfissural, chest wall, and dia- Background Information: Miscellaneous pulmonary conditions phragmatic extension of tumors . Vertebral and sternal metastases produce tumor-like imaging findings that mimic primary lung are easily depicted on coronal or sagittal reconstruction images . cancers and are difficult to distinguish from them . The purpose of this exhibit is to present a wide variety of chest radiographs and Conclusion: 3D imaging using MDCT provides more accu- CT features of pulmonary conditions that mimic lung cancers and rate information, higher diagnostic confidence, and better com- to assess the image clues and clinical background for differentia- munication in staging of patients with lung cancer . tion from cancers . Pathological findings will also be demonstrat- ed in actual cases .

Educational Goals/Teaching Points: The goal is for the learner to recognize miscellaneous pulmonary conditions that cause imaging findings that mimic lung cancers; be familiar with the

200 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

E072. A Single Center Review of CT Pulmonary Angiogram Key Anatomic/Physiologic Issues and Imaging Findings/ Findings and Patient Risk Factors (CME Credit Available) Techniques: Imaging techniques include: chest radiographs, CT, Murphy, G.; Saliti, U.; Knox, M.; Keogan, M. St James’s Hospital, PET-CT . Dublin 6, Ireland Address correspondence to G. Murphy (gillianmurphy78@hotmail. Conclusion: Lung tumors can be classified as epithelial tumors, com) soft tissue tumors, mesothelial tumors, miscellaneous tumors, lymphoproliferative disease, secondary tumors, unclassified Objective: Certain patient groups are felt to be at high risk of tumors, and tumor-like lesions . developing pulmonary embolism (PE) . An audit was performed to establish if patients most at risk were those with a malignancy, intravenous drug users, pregnant, postoperative or immobile E074. CT Halo Sign and Reversed Halo Sign: The Spectrum of patients . Pulmonary Diseases Jeon, K.; Bae, K. Gyeongsang National University Hospital, Jinju, Materials and Methods: A retrospective study was performed South Korea during a 12-month period in 2007 in our institution . Clinical data Address correspondence to K. Jeon ([email protected]) was collected on all patients who underwent a CT pulmonary angiogram (CTPA) from the hospital PACS system . Analysis was Background Information: The CT halo sign may be seen in a performed using statistical package for the social sciences soft- wide spectrum of pulmonary diseases; it is most commonly ware . associated with hemorrhagic nodules and is more rarely associ- ated with tumor cell or inflammatory infiltrate . The reversed halo Results: A total of 659 patients (283 males, 376 females) had a sign refers to a CT finding that consists of a focal ground-glass CTPA . Overall 70/659 (10 .6%) were positive for PE . These includ- attenuation surrounded by denser airspace consolidation . This ed 25/172 (14 .5%) postoperative/immobile patients, 7/57 sign was known to be relatively specific for cryptogenic organiz- (12 .3%) pregnant patients, 17/161 (10 .6%) patients with malig- ing pneumonia . The purpose of this study was to present various nancy and 2/33 (6 .1%) intravenous drug users . Of the patients pulmonary diseases showing the CT halo sign and the reversed who were without these risks, 24/306 (7 .8%) had a PE . Thirty- halo sign . seven of 37 (100%) patients with normal D-dimers had a nega- tive CTPA; 11/43(25%) of patients with a concurrent deep Educational Goals/Teaching Points: The goals are for the view- venous thrombosis (DVT) and 11/84 (13%) of patients with pre- er of this exhibit to understand pathologic basis of the CT halo vious thromboembolic disease had a positive scan . A total of sign and the reversed halo sign; review the imaging findings of 172/659 (26 .1%) had a normal scan . The most common abnor- various pulmonary diseases with the CT halo sign and the mal findings included 165/659 (25%) with consolidation, with reversed halo sign, and know differential points of pulmonary 99 (67%) of these already evident on chest X-ray (CXR) . A total diseases showing the same signs . of 34/659 (5 2%). had indeterminate pulmonary nodules that required followup CT scans . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The CT halo sign and the reversed halo sign are Conclusion: Patients within high risk groups and those with con- seen in more various pulmonary diseases than previously report- current/previous thromboembolic disease had a higher rate of PE ed . We demonstrate the spectrum of pulmonary diseases show- than patients not in these groups . D-dimers had 100% negative ing the CT halo sign and the reversed halo sign and discuss their predictive value . CXRs are mandatory, frequently suggesting an clinical and radiological features with an emphasis on differential alternate diagnosis . A combination of medical history, clinical diagnosis . findings, CXR +/- D-dimers (as per Well’s criteria) are necessary when deciding who should have CTPA . Conclusion: The CT halo sign and the reversed halo sign are seen in more various pulmonary diseases than previously reported . E073. World Health Organization/International Association for the Study of Lung Cancer Classification of Lung and Pleural Tumors: Radiological and Pathological Correlation E075. High-Resolution CT Findings of the Pulmonary El-Sherief, A.; Xu, H.; Wandtke, J. University of Rochester, Vasculitities (CME Credit Available) Rochester, NY Chowdhry, A.; Mohammed, T. Cleveland Clinic, Cleveland, OH Address correspondence to A. El-Sherief (ahmed_elsherief@urmc. Address correspondence to A. Chowdhry ([email protected]) rochester.edu) Background Information: The purpose of this exhibit is to dis- Background Information: This exhibit will review the World cuss the high-resolution CT (HRCT) findings of some of the most Health Organization/International Association for the Study of common pulmonary vasculitities, including Wegener’s granulo- Lung Cancer histological classification of lung and pleural tumors matosis, Goodpasture’s syndrome, Churg-Strauss syndrome, and for the general radiologist . Polyarteritis nodosa . This exhibit will also discuss some unique features of each of these diseases . Educational Goals/Teaching Points: This review of lung and pleural pathological categories includes epithelial tumors, soft tis- Educational Goals/Teaching Points: The major teaching points sue tumors, mesothelial tumors, miscellaneous tumors, lympho- of this exhibit are: HRCT is the imaging modality of choice in proliferative disease, secondary tumors, unclassified tumors, and evaluating patients with pulmonary vasculitis, and imaging is use- tumor-like lesions . ful and important in guiding treatment and future management .

201 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Typical imaging findings in patients who have pulmonary vasculi- E077. From Solitary Pulmonary to Diffuse Pulmonary tis, include pulmonary nodules (with or without cavitation), air- Consolidations: Spectrum of Chest CT Findings Associated space consolidation, and tracheobronchial abnormalities will be with Bronchoalveolar Carcinoma (CME Credit Available) discussed . Cuthbertson, E.1; Duncan, D.2; Spektor, M.2; Lebowitz,Y.2; Khan, A.2 1. No Institutional Affiliation; 2. Long Island Jewish Medical Key Anatomic/Physiologic Issues and Imaging Findings/ Center, Glen Oaks, NY Techniques: This exhibit will outline the frequency of pulmonary Address correspondence to D. Duncan ([email protected]) vasculitities in the general population; discuss the role that HRCT has in evaluating patients with these diseases; review the most Background Information: This exhibit will showcase an array of common imaging findings, and discuss how imaging can be used CT findings associated with bronchoalveolar carcinoma (BAC) to evaluate treatment response and guide management . Sample with pertinent differential diagnosis . Histopathologic correlation cases will be provided . and the association of BAC with adenocarcinoma will also be described . Conclusion: HRCT is the imaging modality of choice in evaluat- ing patients with pulmonary vasculitis . Typical imaging findings in Educational Goals/Teaching Points: The exhibit will outline the patients who have pulmonary vasculitis, include pulmonary nod- demographics and natural history of BAC and the various chest ules (with or without cavitation), airspace consolidation, and tra- CT appearances of BAC which include: Focal Disease (80%)— cheobronchial abnormalities . Imaging is useful and important in small peripheral nodule(s) or masses, focal ill defined airspace guiding treatment and future management . opacities simulating pneumonia (30%), lobar consolidations causing lobar expansion and fissural bulging, and elongated opacities simulating mucoid impaction (rare); Diffuse Disease E076. : Radiological Findings (20%)—diffuse pulmonary consolidations simulating pneumonia, and Pitfalls and diffuse nodules, miliary or larger in size . Pauls, S.1; Katenkamp, D.2; Brambs, H.1; Possekel, A.1 1. University of Ulm, Ulm, Germany; 2. University of Jena, Jena, Key Anatomic/Physiologic Issues and Imaging Findings/ Germany Techniques: Multislice CT and plain film will be used to demon- Address correspondence to S. Pauls ([email protected]) strate CT findings in BAC .

Background Information: The symptoms of patients with lym- Conclusion: At this presentation’s conclusion, the participant phangioleiomyomatosis (LAM) are often uncharacteristic . The should have learned the various chest CT manifestations of bron- average time between the first clinical manifestation and the choalveolar carcinoma with pertinent differential diagnosis and diagnosis is about five to six years . Therefore, imaging methods histopathologic correlation . play a key role in making a definitive diagnosis .

Educational Goals/Teaching Points: The viewer of the exhibit E078. Pulmonary Nodule Evaluation: Current Concepts will learn about the etiology of LAM, about the association with Godoy, M.; Nonaka, D.; Naidich, D. New York University, New other diseases, about the clinical presentation and the differential York, NY diagnosis in imaging methods (for example congenital cysts, cen- Address correspondence to M. Godoy ([email protected]) trilobular emphysema, Langerhans cell histiocytosis, lymphomas, lymphocele, pseudomyxoma peritonei) and new therapeutic Background Information: New reported data in the literature is regimes . In addition, the viewer will gain knowledge of typical currently redefining lung nodule characterization, particularly radiological findings in LAM with thoracic and abdominal mani- regarding subsolid pulmonary nodules and its correlation to ade- festation . Rare imaging findings and pitfalls are demonstrated . nocarcinoma of the lung . The purpose of this educational exhibit is to review and illustrate clinical, radiological and pathological Key Anatomic/Physiologic Issues and Imaging Findings/ aspects of adenocarcinoma of the lung . In addition, we review Techniques: LAM is characterized by typical pulmonary cystic current approach to pulmonary nodules detected by CT, and we lung lesions and lymphatic disorders . An abdominal manifesta- discuss the optimal approach to diagnosis and management tion – especially without pulmonary disorders – is very rare . of subsolid nodules . Multidetector row CT as an imaging method of choice is able to detect lymph node enlargement, cystic changes including multi- Educational Goals/Teaching Points: Subsolid pulmonary nod- ple intrahepatic cystic lesions and a cisterna chyli . Mesenterial ules include pure ground-glass opacity (GGO) and mixed part masses can be fatty or liquid presenting different types of lym- solid/part ground-glass nodules . Subsolid nodules are now phangioleimyomas, which can be distinguished with the meas- known to frequently represent adenocarcinoma and its spectrum urement of Hounsfield units on CT . Intramural cystic formations of disease, including premalignant atypical adenomatous hyper- in the small bowel wall and the colonic wall are extremly rare plasia (AAH), bronchoalveolar carcinoma (BAC), mixed BAC/inva- findings . In association with complex, menin- sive adenocarcinoma and pure invasive adenocarcinoma . geomas and renal or hepatic angiomyolipoma are observed . Correlation between Noguchi pathological classification and CT appearance of pulmonary nodules has been established . CT find- Conclusion: Radiologists should not only know the typical find- ings, in particular growth and relative contribution of ground- ings of LAM . To make a correct diagnosis, it is also necessary to glass to solid elements, have been demonstrated to predict recognize rare radiological findings of the pulmonary and abdom- malignancy and prognosis . Evaluation of serial CT findings has inal manifestation of LAM and regard them before making a final demonstrated stepwise progression of ground-glass lesions, diagnosis . showing increase in size, appearance of solid component and subsequent increase of the extent of the solid component . 202 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Differential diagnosis for subsolid nodules includes benign E080. Pulmonary Manifestations of Pneumocystis Carinii lesions, such as nodular fibrosis . Recognition of suspicious mor- Pneumonia in HIV: A Pictorial Essay phology and accurate measurements of volume doubling time Morgan, J .; Allmendinger, A .; Krauthamer, A .; Hwang, B ;. Perone, should aid in the management of these lesions . R . St. Vincent’s Hospital and Medical Center, New York, NY Address correspondence to J . Morgan (jmorgan911@aol com). Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Based on current knowledge, we suggest that pure Background Information: Pneumocystis carinii pneumonia GGO’s larger than 1 cm in size should be assumed as BAC/aden- (PCP) is a common opportunistic infection associated with ocarcinoma provided stability for at least three months, although human immunodeficiency virus (HIV) disease . Although the inci- up to 20-25% will prove to be benign . Mixed solid/GGO lesions dence of pulmonary infection has decreased in the past few should also be presumed as malignant . Surgical resection should years secondary to antiretroviral therapy, prompt identification of be considered for mixed solid/GGO nodules, especially if larger the pulmonary manifestations are important for early initiation of than 1 cm or growing, and for pure GGO’s larger than 1 cm if therapy . The typical and atypical as well as acute and chronic growing or if they develop solid components . For GGO’s larger manifestations of PCP in the lung will be discussed . than 5 mm and smaller than 1 cm long term follow-up is requi- site pending better definition of its true significance . Educational Goals/Teaching Points: The exhibit will review both acute and chronic as well as typical and atypical roentgeno- Conclusion: While controversial, reassessment of our approach graphic manifestations of PCP and discuss important emergency to small pulmonary nodules is necessary as we increase our plain film findings and the added value of CT to aid in diagnosis . knowledge of the natural history and CT appearance of small It will also discuss the sensitivity and specificity of various diag- adenocarcinomas of the lung . nostic modalities in disease detection and characterization .

Key Anatomic/Physiologic Issues and Imaging Findings/ E079. Acute Pulmonary Embolism in Patients With Chronic Techniques: The exhibit will review the etiology and pathophysi- Obstructive Pulmonary Disease Exacerbation ology of pulmonary PCP; apply the pathophysiology of the dis- Talanow, R.1; Timofte, I.2 1. The Cleveland Clinic, Cleveland, OH; ease process both in its acute and chronic forms to the imaging 2. Huron Hospital, East Cleveland, OH manifestations on chest radiographs and CT, and provide cases of Address correspondence to R. Talanow ([email protected]) less typical manifestations of PCP and potential complications .

Objective: Acute pulmonary embolism and chronic obstructive Conclusion: Although the incidence of PCP has been decreasing pulmonary disease (COPD) exacerbation are difficult to distin- in recent years in the HIV population, early imaging identification guish by clinical signs and symptoms . Lung CT angiography (CTA) and characterization remains critical for expedient diagnosis and and ventilation-perfusion (VQ) scans are currently used in the treatment crucial to patient survival . In this pictorial essay, we evaluation of pulmonary embolism (PE) . The objective of the hope to summarize the imaging findings of both acute and study was to investigate the incidence of PE in patients with chronic, as well as typical and atypical pulmonary PCP to help acute COPD exacerbation and to assess the necessity of perform- facilitate the above goal . ing CTA or VQ scans in these patients .

Materials and Methods: We retrospectively reviewed 3,282 E081. MDCT Evaluation of Large Airway Disease charts of all patients that presented to Cleveland Clinic emergen- Kakarla, R.; Gelshenen, K.; Kirshenbaum, K. Illinois Masonic cy department between January, 2001 and December, 2006 with Medical Center, Chicago, IL acute COPD exacerbation . We selected the cases that had a lung Address correspondence to R. Kakarla ([email protected]) CTA or a VQ scan as the initial investigation for a possible PE . Background Information: Trachea and main stem bronchi are Results: VQ scans were initially done in five patients with COPD affected by a variety of disease entities . MDCT is a powerful tool exacerbation and were all low probability for PE . CTA was per- is assessment of large airway disease that can provide comple- formed in 74 of the 3,282 patients with acute COPD exacerba- mentary information to clinical findings and bronchoscopy . tion and was negative and indeterminate for pulmonary embo- lism in 68 and five patients, respectively . There were no positive Educational Goals/Teaching Points: The exhibit will delineate CTA results . From the six patients that had an indeterminate CTA, normal appearance of trachea and main stem bronchi on MDCT; two patients had a normal VQ scan, one patient had extensive present imaging features of pathologic entities involving large air- lung metastasis, one patient had extensive pneumonia, and one ways, and discuss the utility of 3D imaging and reconstruction patient had a mucus plug . algorithms in diagnosis and follow-up of patients .

Conclusion: Our study did not reveal an increased incidence of Key Anatomic/Physiologic Issues and Imaging Findings/ PE in patients with acute COPD exacerbation . None of the Techniques: The exhibit will focus on: Focal Large Airway patients had a positive CT for pulmonary embolism . Thus, pulmo- Disease, including tracheal stricture and (primary or nary embolism in the acute setting of COPD exacerbation is secondary); Diffuse Large Airway Diseases, including tracheobron- extremely unlikely . chopathia osteochondroplastica, infections, inflammatory diseas- es, relapsing polychondritis, saber sheath trachea, granulomatous disease, sarcoidosis, Wegener’s, Mounier-Kuhn syndrome, and amyloidosis; and tracheobronchomalacia . It will feature 3D imaging/reconstruction techniques .

203 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Conclusion: Tracheal and bronchial wall thickening and narrow- widely used to exclude PE in patients with a low probability of ing have a wide variety of causes . Recognizing locations of abnor- having a PE . Patterns of referral related to D-dimer results have malities can allow one to narrow differential diagnosis . As one been variable . As clinicians have become more reliant on CTPA for incorporates clinical and bronchoscopy findings, when available, the diagnosis of PEs, weighing the risk and benefit of CTPA and CT patterns allow for accurate diagnosis even when symptoma- determining the frequency of positive studies is important . tology is nonspecific . However, given the variable clinical presentation of PEs, evalua- tion of other pathologies seen would be helpful for clinicians and radiologists . It would also be of value to correlate dD results with E082. Cystic Lung Disease Spectrum: CT and HRCT Imaging the results of CTPA studies . Patterns Kakarla, R.; Bhatia, S.; Kirshenbaum, K. Illinois Masonic Medical Materials and Methods: A retrospective review of 398 CTPAs at Center, Chicago, IL HHSC from May, 2004 to December, 2005 was completed . Address correspondence to R. Kakarla ([email protected]) Studies with the heading “CT-Pulmonary Angiogram” were included . There were no exclusion criteria . Data was collected by Background Information: The wide range of the disease spec- two independent reviewers . Clinical history from the referring cli- trum that present as diffuse cystic lung disease can pose a diag- nician, risk factors for PE, patient age and gender, PE positive, nostic dilemma for the clinician and diagnostic radiologist . CT and dD status were recorded . Broad categories for other thoracic and specifically high resolution CT (HRCT) is an invaluable tool in findings (pleural/pericardial effusion, airspace disease, adenopa- assessment of structural changes that occur in pulmonary paren- thy, tumor, metastases, emphysema, congestive heart failure) chyma in the diffuse interstitial lung diseases . were also included . A Chi squared analysis was complet- ed between dD findings/other pathologies in relation to positive Educational Goals/Teaching Points: The goals are to illustrate PE findings . a spectrum of common and rare cystic diseases involving the lung and to delineate patterns of presentation on CT and HRCT Results: The frequency of PE in the reviewed studies was 23% . of diffuse cystic lung disease and outline an approach to narrow Shortness of breath was the most common symptom at presen- the differential diagnosis through incorporation of clinical find- tation . A trend for positive CTPAs were seen in older patients ings . (>60 years) . A total of 41% had dDs performed with 73% posi- tive and 27% negative . 18% and 2 4%. of patients had PEs, Key Anatomic/Physiologic Issues and Imaging Findings/ respectively . The most common other pathologies were air space Techniques: This is a retrospective review of thoracic CT and disease (71%) and pleural effusions (47%); 13% of patients had HRCT database and correlation with literature review to delineate no other pathology; 2% of patients had PE only and 11% had no imaging patterns of cystic lung disease . It will focus on: Adult pathology at all . Diffuse Cystic Disease, including Langerhans cell histiocytosis, pulmonary lymphangioleiomyomatosis, tuberous sclerosis, lym- Conclusion: Given that only 11% of patients had no pathology phoid interstitial pneumonia, congenital cystic adenomatoid mal- at all, CTPA remains a useful test in evaluating not only for the formation, and idiopathic pulmonary fibrosis with honeycombing; presence of PE, which occurred in almost a quarter of the Pediatric Diffuse Cystic Disease, including congenital cystic ade- patients, but also for the presence of other significant patholo- nomatoid malformation and bronchopulmonary dysplasia; and gies . The usual symptoms associated with PE were not significant mimics, including cystic bronchiectasis, emphysema, and congen- predictors of a positive CTPA . In the setting of a negative dD in a ital diaphragmatic hernias . low probability patient, CTPA should be used judiciously .

Conclusion: CT and HRCT are invaluable tools in the approach to assessment of cystic lung disease . Recognition of patterns of E084. Revisiting Arteriovenous Malformations: Radiologic presentation on HRCT, including size, location, distribution, and and CT Imaging Characteristics and Corresponding associated findings is essential for accurate diagnosis . Correlation Treatment Options of HRCT findings with clinical information allow one to narrow Poole, P.; Ferguson, E. University of Texas at Houston, Houston, TX the differential diagnosis . Address correspondence to P. Poole ([email protected])

Background Information: Pulmonary arteriovenous malforma- E083. CT Pulmonary Angiograms: Pulmonary Emboli, tions (PAVM) are quite uncommon . However, they are an impor- Pulmonary Emboli Plus or No Pulmonary Emboli–A tant part of the differential diagnosis in patients with solitary pul- Canadian Experience monary nodule or hemoptysis . PAVMs can be congenital, Muhn N.1,2; Choudur H.1,2 1. Hamilton Health Sciences–General acquired or associated with a genetic syndrome . The imaging Site, Hamilton, Canada; 2. McMaster University, Hamilton, characteristics vary greatly in size, distribution and associated Canada findings, and can be overlooked or mistaken for common mim- Address correspondence to N. Muhn ([email protected]) icking processes .

Objective: CT of the pulmonary arteries (CTPA) has replaced Educational Goals/Teaching Points: This exhibit will review the invasive angiography for diagnosing pulmonary emboli (PE) plain film and CT characteristics most useful for establishing the but carries with it a significant radiation dose and possible diagnosis of PAVM; define some of the associated findings that adverse contrast reaction . The increased use and lower threshold suggest a congenital, acquired or genetic etiology; discuss com- in ordering CTPA in the Hamilton Health Science Corporation mon mimics of PAVMs and how they can be distinguished from (HHSC) has been noticeable . D-dimer (dD) testing has been PAVMs on plain film and CT; discuss the plain film and CT imag-

204 El e c t r o n i c Ex h i b i t s : Cardiopulmonary ing characteristics most useful for differentiating simple from Results: The predominant symptoms were dyspnea (n=161), complex lesions, including size, distribution, and associated find- cough (n=114), and chest (n=76) . The most common cause ings, and review the treatment of PAVMs and how imaging find- of PE was congestive heart failure/pericarditis (n=75; 30%) fol- ings contribute to treatment plans . lowed by malignant tumor (n=44; 17 6%),. infection (n=38; 15 .2%), idiopathic (n=35; 14%), paraneoplastic (n=26; 10 .4%), Key Anatomic/Physiologic Issues and Imaging Findings/ pancreatitis (n=13; 5 .2%), postradiation (n=8; 3 .2%), pulmonary Techniques: This presentation will discuss the plain film and CT embolism (n=7; 2 8%),. connective tissue diseases (n=2; 0 .8%), imaging findings of PAVMs, including what processes can mimic myxedema (n=1; 0 4%),. and sarcoidosis (n=1; 0 4%). . A total of them and the approach to single or multiple lesions . We will 127 PEs were transudates and 123 were exudates . Small to mod- identify what defines a simple vs . complex lesion and the corre- erate (n=132; 52 8%),. large (n=80; 32%), and massive (n=38; sponding imaging characteristics most useful in diagnosing and 15 .2%) PEs were seen . Congestive heart failure/pericarditis was categorizing the PAVM . In addition, we will discuss how the imag- associated with bilateral small (n=70) or unilateral large PEs ing findings contribute to treatment decisions and what the radi- (n=5) . Malignant PEs were unilateral massive (n=27), or large ologist should communicate to the clinician regarding the find- (n=17) . Infectious PEs were unilateral small (n=33) or massive ings . (n=5) . Idiopathic PEs were most commonly unilateral large (n=30) or small (n=5) . Paraneoplastic PEs were unilateral large Conclusion: At the end of this presentation the radiologist will (n=20) or massive (n=6) . PEs due to pancreatitis, pulmonary be able to recognize the imaging characteristics found with sim- embolism and myxedema were unilateral small (n=21) collec- ple and complex PAVMs and how the pattern of findings suggest tions, whereas postradiation PEs were exclusively unilateral large the etiology . In addition, the radiologist will be able to recognize collections (n=8) . Connective tissue diseases and sarcoidosis the associated imaging findings commonly found with congeni- were associated with bilateral small PEs (n=3) . tal, acquired and genetic causes of PAVMs . Currently there are many treatment options for PAVMs, including percutaneous Conclusion: MDCT combined with postprocessing tools proves embolization using coils or balloons, surgical techniques includ- particularly useful in defining the location, morphology and ing local excision, segmental resection, lobectomy, ligation, pneu- extent of PE . CT findings coupled with clinical and laboratory monectomy, or video assisted thoracoscopy . The decision for no data can suggest or establish a specific cause for the PE . treatment vs . invasive treatment and what form of invasive treat- ment is often based on the clinical status, as well as the reported imaging findings . Therefore, this presentation will aid radiologist E086. Imaging of Broken Sternal Sutures: Evaluation of in how to report imaging findings, including the importance of Findings and Clinical Implications (CME Credit Available) size, distribution, feeding vessels, and possible complications Gerard, P.1; Lefkovitz, Z.2; Kupfer Y.1; Hersh, J.1; Nikac, V.1 1. from the lesions that commonly affect the treatment plan . Maimonides Medical Center, Brooklyn, NY; 2. Mount Sinai Medical Center, New York, NY Address correspondence to P. Gerard ([email protected]) E085. 16-Row MDCT of the Chest and Postprocessing Techniques: Assessment of Pleural Effusion and Correlation Background Information: This exhibit will discuss the impor- with Clinical and Biochemical Analysis tance in the recognition and reporting of broken sternal sutures Theodorou, D.1; Theodorou, S.1; Kakitsubata, Y.2; Tsampoulas, in the interpretation of plain chest radiographs and imaging pro- C.1,3 1. University of California, San Diego; San Diego, CA; 2. cedures and the potential complications of broken sternal Miyazaki Shakaihoken Hospital, Miyazaki, Japan; 3. University of sutures, including local and intravascular migration and potential Ioannina, Greece, Ioannina, Greece fatal outcomes . Address correspondence to S. Theodorou (rjtheodorou@hotmail. com) Educational Goals/Teaching Points: Sternal sutures are rou- tinely encountered on a daily basis in poststernotomy patients, in Objective: MDCT scanners with increased volume coverage and both hospital and private imaging settings . When broken sternal thin detector collimation provide high-resolution multiplanar sutures are encountered, they are frequently not reported . We reformatted (MPR) images, with or without application of maxi- discuss our experience in the reporting of these findings, and mum intensity projection (MIP) techniques . We assessed the role report potential complications of broken sutures, possible life of postprocessing techniques using 16-row MDCT in patients threatening consequences, and why they should be reported rou- with pleural effusion (PE) . tinely in all cases where they are recognized .

Materials and Methods: A total of 250 patients with 321 PEs Key Anatomic/Physiologic Issues and Imaging Findings/ were evaluated with 16-row MDCT and diagnostic thoracentesis . Techniques: A wide array of case examples will be presented, There were 152 male and 98 female patients, with an age range including a pictorial of plain film and CT appearance of broken of 35-84 years (mean age, 59 .5 years) . The medical records with sutures, discussion of why sternal sutures break, cases of local special attention to history and symptoms, biochemical parame- and distant suture migration, local skin reactions to broken ters, culture, and cytologic examination of the pleural fluid were sutures, and show the critical reasons why these broken sutures reviewed . CT axial and multiplanar reconstructions with or with- should be recognized and reported . The role and importance of out MIP images were created . CT scans were evaluated for locali- the radiologist reporting these findings will be emphasized . Cases zation, distribution, and size of PE . The CT protocol that allowed will be correlated with other imaging modalities, including the CT acquisition of high-quality 2D reformations is presented . identification of critical findings .

205 El e c t r o n i c Ex h i b i t s : Cardiopulmonary

Conclusion: We will demonstrate the various plain film findings nary nodules is important in decreasing morbidity and mortality . and imaging appearances of broken sternal sutures . We believe Recent studies indicate that computer-aided detection (CAD) that every case of broken sternal wires should be documented software is a useful adjunct to the interpreting radiologist in and reported by the radiologist, which is not currently routinely improving sensitivity and specificity of early nodule detection on performed . The postoperative chest radiograph and CT study plain film . Recently, dual energy subtraction (DES) enables the radiologist to issue the earliest warning of possible radiography has emerged and studies have demonstrated impending complications . This reporting would allow the treating improved detection of subtle lung nodules using this technique . clinician to take appropriate measures in both the prevention We therefore hypothesize that the combined use of computer- and management of unexpected emergencies . aided detection software with dual energy radiography will have an additive benefit in nodule detection .

E087. Congenital Vascular Anomalies of the Mediastinum Materials and Methods: We compiled a set of 36 patients with Sartip, K.; Gakhal, M. Christiana Care Health Services, New a total of 56 CT-proven and pathology-proven malignant lung Castle, DE nodules who underwent DES radiography (GE Medical Systems, Address correspondence to K. Sartip ([email protected]) Milwaukee, WI) at our institution . Twenty-five DES exams without positive findings were also included as a control set . We utilized Background Information: Various congenital vascular anoma- a computer-aided detection program (Riverain Medical, lies of the mediastinum may be encountered during interpreta- Miamisburg, OH) to identify and mark regions of interest (ROI’s) tion of thoracic studies . Some of these anomalies may be clini- on the DES images . These ROI’s were compared with actual find- cally significant such as those causing extrinsic impression of ings (“truths”) as determined by an experienced chest radiologist . adjacent structures or changes in cardiovascular physiology . This Sensitivity, specificity, and false positives per case (FPPC) values exhibit will review, through case example, various congenital vas- were obtained for both the plain film (PA) and bone subtracted cular anomalies of the mediastinum while discussing their clinical images (BSI) . Differences in sensitivity between the PA and BSI significance . images were measured by the Chi-square and proportional dif- ferences test . Educational Goals/Teaching Points: The exhibit will describe congenital arterial and venous anomalies of the mediastinum Results: The use of the bone subtracted image with CAD signifi- through case example and discuss clinical significance of congen- cantly improved sensitivity of nodule detection (47 .1% vs . 66 .7 ital mediastinal vascular anomalies such as extrinsic impression %: p=0 022). when compared to the PA image . In addition, FPPC of adjacent structures, associated syndromes and organ abnor- was significantly reduced from 1 69. to 0 67. when the PA image malities, changes in cardiovascular physiology, and relevant was compared to BSI (Chi squared=6 .92, p=0 008). . issues regarding interventional procedures . Conclusion: Dual energy subtraction radiography in conjunction Key Anatomic/Physiologic Issues and Imaging Findings/ with computer-aided detection software significantly improves Techniques: Cross-sectional imaging with radiographic/fluoro- detection of subtle malignant pulmonary nodules . In addition, scopic correlation, maximum intensity projection, and volume there is a significant reduction in false positive findings . This tech- rendered images will be utilized . Mediastinal arterial anomalies nique is therefore a promising advancement in the early detec- involve the aortic arch and include right sided aortic arch with tion of lung cancer . aberrant left subclavian artery, mirror image right aortic arch, double aortic arch, aberrant right subclavian artery with diverticu- lum of kommerell, pulmonary sling, coarctation, and pseudoco- E089. A Free and Customized Online Tool to Facilitate Quick arctation . Examples of venous anomalies include persistent left and Accurate Staging of Common Mediastinal Malignancies superior vena cava, azygous and hemiazygos continuation of infe- Talanow, R.1; Timofte, I.2; Giesel, F.3 1. The Cleveland Clinic, rior vena cava, and total or partial anomalous pulmonary venous Cleveland, OH; 2. Huron Hospital, East Cleveland, OH; 3. German return . The authors will describe these anomalies through case Cancer Research Center (DKFZ) Heidelberg, Heidelberg, Germany example while emphasizing their clinical significance Address correspondence to R. Talanow ([email protected])

Conclusion: Congenital vascular anomalies of the mediastinum Background Information: Complex cancer staging systems can be incidental or clinically significant discoveries during radio- describe the anatomic spread of a particular malignancy . Staging logic examinations . Knowledge and recognition of their clinical provides prognostic information and is vital in guiding appropri- significance is essential for image interpretation . ate therapy . However staging can be difficult to perform for the inexperienced physician and inaccurate staging can lead to an adverse patient outcome . The author provides a free, comprehen- E088. Analysis of Computer-Aided Detection Software with sive, Web-based, on-the-fly solution which is easy to use and aids Dual Energy Subtraction Radiography in the Assessment of in accurate staging of common mediastinal malignancies . Malignant Pulmonary Nodules on Chest X-Ray (CME Credit Available) Educational Goals/Teaching Points: The goal was to create a Mehandru, S.; Novak, R.; Gilkeson, R. University Hospitals Case free, Web-based and customized staging tool for common medi- Medical Center, Cleveland, OH astinal cancers, which easily integrates into the radiologist’s daily Address correspondence to S. Mehandru (smehandru@gmail. work from any monitor or PACS station . com) Key Anatomic/Physiologic Issues and Imaging Findings/ Objective: Lung cancer remains the most common cancer diag- Techniques: The tumor classification information is based on the nosis in the United States . Early detection of neoplastic pulmo- Collaborative Staging Network . On-the-fly staging is done by cal- 206 El e c t r o n i c Ex h i b i t s : Efficacy, PACS culating and comparing the information provided by the user with the tumor classification database saved on the server . The staging Ef f i c a c y , Ed u c a t i o n , tool can be used in several modes for the user’s convenience . Output of information is also offered in several modes to increase Administration a n d PACS flexibility and better integration into the reader’s workflow . E091. The Role of Oral and IV Contrast in CT Scanning: Conclusion: This software is an intuitive, user friendly education- Advantages, Risks and Complications–A Practical Approach al program which makes staging of mediastinal malignancies for the Nonradiologist (CME Credit Available) easy and accurate . Fishman, E. Johns Hopkins Hospital, Owings Mills, MD Address correspondence to E. Fishman ([email protected])

E090. Determination of Central Line Position in the Superior Background Information: The use of oral and IV contrast is crit- Vena Cava or Azygous Vein on Frontal Chest Radiographs ical in body CT . Yet many of the individuals who are part of the Haygood, T.1; O’Sullivan, P.1; Yamal, J.1; Liles, L.2; Madewell, J.1; clinical process have minimal knowledge of contrast including Chasen, B.1; Fitzgerald, N.1; Costelloe, C.1; Ng, C.1; Sandler, C.1; why it is used, potential contraindications and the importance of Lano, E.1; McEnery, K.1; Murphy, Jr. W.1 1. U. T. MD Anderson contrast in clinical applications . This computer program is Cancer Center, Houston, TX; 2. Harvard University, Cambridge, MA designed to be both a teaching and reference tool for our refer- Address correspondence to T. Haygood (tamara.haygood@di. ring clinicians, nursing staff in and outside of radiology as well as mdacc.tmc.edu) a resource for technologists and radiologists . The format of this program is a “how to guide” with more than 100 specific ques- Objective: Many malpositions of central venous lines are obvious tions which are answered with references when possible . Select on a frontal chest radiograph (PA CXR) . Clinical observation sug- images are also provided to make key points (i .e . positive vs . gests that the most common malposition that is difficult to per- neutral oral contrast agents) . The program is designed as an easy ceive on PA CXR is the tip of the line in the azygous vein . We test- to use Web-based program making it accessible on a 24/7/365 ed radiologists’ ability to distinguish placement in the superior basis . vena cava (SVC) from placement in the azygous using the PA CXR . Educational Goals/Teaching Points: This exhibit will answer Materials and Methods: Nine radiologists viewed 80 randomly- the following questions: 1 . why do we use oral contrast and ordered PA CXRs of patients with central lines, in two batches of what are its advantages and disadvantages? how, when and why 40, with each batch consisting of 20 PA CXRs common to both, do we give it? 2 . why do we use IV contrast agents and what are and 20 unique PA CXRs . They graded the position of the line: its potential risks? 3 . how do we handle patients with suspected definitely, probably or possibly in the SVC, or definitely, probably contrast allergies? premedication schemes, selection of agent, or possibly in the azygous . Each batch of PA CXRs included 20 alternatives? 4 . what about the role of creatinine and glomerular central lines in the SVC and 20 in the azygous . Half of the 20 that filtration rate in patient selection? 5 . what do we do with the dia- were in both batches were in the SVC and half in the azygous . betic, the patient with myeloma, the patient with sickle cell dis- Five of nine readers looked first at cases 1-40 . Four of nine read- ease, etc ?. 6 . what about rectal, and intravesical contrast? 7 . what ers looked first at cases 41-80 . Truth was determined by inde- about informed consent? pendent review by 2 investigators who consulted lateral views and other imaging as needed and available . Only cases on which Key Anatomic/Physiologic Issues and Imaging Findings/ both investigators agreed were included in the study images . Techniques: The role of oral and IV contrast in body CT, risks of These investigators did not serve as readers . contrast, management of risks, decisions in select patients like the diabetic, the patient with myeloma, the patient with sick- Results: If the cutoff dividing a correct from an incorrect answer le cell disease, etc . and the importance of oral and IV contrast in was between “possibly SVC” and “possibly azygous,” images patient care will be discussed . were correctly classified between 76% and 97 .5%, with mean 90% for the nine readers . Only 39% of “possibly SVC” readings Conclusion: This exhibit provides a handy online how to guide were correct . 86% of “possibly azygous” readings were accu- for the use of oral and IV contrast as well as answering 100 of rate . If we omit all “possibly” readings, correct classification is the most common questions on the use of contrast by our col- between 80% and 97 .5%, with mean 92% . For the 20 cases leagues in and outside of radiology . included in both batches of readings, in 125 of 180 readings (69%) readers gave the same response both times . For 38 of 180 readings (21%) readers gave the same catheter location but E092. Learning Radiology: Introduction to the Imaging changed their confidence level . For 17 of 180 readings (9%) Modalities (CME Credit Available) readers changed the location of the catheter . McNulty, N. Dartmouth-Hitchcock Medical Center, Lebanon, NH Address correspondence to N. McNulty (Nancy.McNulty@hitch- Conclusion: Accuracy was 90% or 92% if we ignore the “possi- cock.org) bly” answers and evaluate only those showing a higher level of confidence . Thus, though accuracy was not bad, there was room Background Information: Utilizing radiographs, CTs and MRIs for improvement . Readers were fairly consistent in their decisions to teach normal anatomy is playing an increasing role in the edu- for the 20 PA CXRs that were included in both batches of images . cation of first-year medical students during the anatomy courses, We intend next to investigate the influence of specific training on however, the busy curriculum at most institutions does not allow accuracy of interpretation of the central line position and also to for dedicated lectures on these imaging modalities prior to the investigate the contribution of the lateral CXR to accuracy . students being exposed to them . This leads to student frustration and suboptimal learning, as they often do not understand what 207 El e c t r o n i c Ex h i b i t s : Efficacy, PACS they are looking at . “Introduction to Radiology” is a Web-based scroll functions through CT image stacks and window/level learning module created to introduce the common imaging functions . Pre- and post-tests evaluate the learning progress . Free modalities to the learner . The target audience is those with no text search and predefined menus allow individual display of prior exposure to radiology; this was created primarily for the contents . education of first year medical students . Conclusion: We present an interactive tutorial which serves jun- Educational Goals/Teaching Points: The goal of this learning ior radiology residents and also clinical residents as a compre- module is to educate the first time user about common imaging hensive learning tool as well as a quick reference to become modalities; radiography, CT, MRI, ultrasound, and fluoroscopy . familiar with on call and emergency findings . Free online access Teaching points include the technique of image creation, the fac- makes it constantly and quickly available and interactivity helps tors which influence the appearance of the images, what struc- to accommodate the user’s needs to enhance the learning expe- tures and organs are seen well with the modality, and limited rience . indications for use of the modality . To further achieve these goals, there is a quiz at the end of each module to ensure a thorough E094. Chestradiology.net–A Valuable Educational Interactive understanding of the material covered . Chest Anatomy Tutorial for Residents and Medical Students Talanow, R.1; Timofte, I.2; Jend, H.3 1. The Cleveland Clinic, Key Anatomic/Physiologic Issues and Imaging Findings/ Cleveland, OH; 2. Huron Hospital, East Cleveland, OH; 3. Klinikum Techniques: Key points include discussion of how images are Bremen Ost, Bremen, Germany displayed and viewed, the strengths and limitations of each Address correspondence to R. Talanow ([email protected]) modality with regard to displaying normal structures, and the fac- tors influencing the appearance of structures on the images . This Background Information: It can be difficult particularly for inter- enables the learner to predict what structures will look like on a nal medicine residents and less experienced physicians who are given modality and to recognize normal anatomy . This basic not specialized in chest radiology to differentiate between physi- knowledge will also aid in determining when pathology is ological thoracic structures and normal variants from pathological present, and what the pathophysiologic basis for that pathology findings on plain film and CT . We designed an interactive, step- is . This program is interactive and has numerous pictorial exam- by-step tutorial in order to teach residents and refresh informa- ples which demonstrate the concepts, including normal and tion about benign and malignant findings in chest imaging . abnormal clinical images, images of fruit, vegetables and inorgan- ic matter . The quiz at the end of each module allows for interac- Educational Goals/Teaching Points: This online chest tutorial tive assessment of the understanding of the concepts presented . (“chestradiology .net”) consists of more than 150 pages and more than 80 images covering plain film and CT . Chapters offer learn- Conclusion: Despite its nearly ubiquitous use in clinical medi- ing material about techniques, standard exams, projections, air- cine and increasing use in teaching anatomy, there is typically no ways, lung parenchyma, heart and vessels, mediastinum, dia- formal instruction in radiology at accredited US medical schools, phragm, pleura, pathology . Pre- and post-tests evaluate the edu- however, students begin looking at these images as early as the cational experience . Twenty-seven internal medicine residents first year of medical school . This instructional module, primarily and medical students were asked to answer ten different ques- created for the anatomy courses taken during medical school, tions on the topic covered in the Website . After a one hour tutori- allows self-directed learning of the imaging techniques common- al the same questions were given to them in order to evaluate ly used in teaching and clinical practice . the learning progress . The educational value of this chest tutorial was then assessed using the results of the pretutorial and post- tutorial questionnaire . E093. Prepared for Call? A Web-Based, Interactive Tutorial and Reference Database for On Call Radiology Findings Key Anatomic/Physiologic Issues and Imaging Findings/ (CME Credit Available) Techniques: Pre- and post-tests evaluated the learning progress Talanow, R. The Cleveland Clinic, Cleveland, OH before and after reviewing the tutorial, respectively . Initially most Address correspondence to R. Talanow ([email protected]) residents and students were able to answer only 2-3 basic ques- tions out of ten regarding chest anatomy (20%-30%) . After Background Information: Junior residents who have not yet spending one hour on this Web-based interactive tutorial that started their emergency room rotations and have limited experi- briefly presented the radiology Web site the same residents and ence with emergency cases may encounter unknown case sce- medical students were asked to answer the same questions . narios, leading to incorrect interpretation and potentially resulting Most residents answered 6-7 questions 60%-70% . in wrong management and patient’s harm . Conclusion: We present an interactive tutorial which serves clini- Educational Goals/Teaching Points: An interactive tutorial is cal residents and medical students as a comprehensive learning desired which prepares the junior radiology resident for the first tool as well as a quick reference to become familiar with physio- call . logic and pathologic findings in chest imaging . Junior radiology residents might also benefit from this program . Free online Key Anatomic/Physiologic Issues and Imaging Findings/ access makes it constantly and quickly available and interactivity Techniques: This online tutorial consists of more than 100 pages helps to accommodate the user’s needs to enhance the learning and thousands of images with emergency cases . Multiple chap- experience as demonstrated in our study . Our study demon- ters cover chest, abdomen/pelvis, musculoskeletal, neuroradiolo- strates that the interactive tutorial is a valuable educational meth- gy and OB/GYN . Interactive tools adapt to the user’s needs . Case od, teaching medical students and residents to differentiate presentations mimic real scenarios at the workstation, offering between physiological and pathological findings on chest x-ray and CT . 208 El e c t r o n i c Ex h i b i t s : Efficacy, PACS

E095. Lymphoma Staging Made Easy! A Free and Customized for any questions encountered during the study period . Over a Online Tool to Facilitate Quick and Accurate Lymphoma six-month period, we analyzed the ordering pattern for medical Staging (CME Credit Available) interns who did not receive the intervention (July through Talanow, R. The Cleveland Clinic, Cleveland, OH December, 2006), and compared it to those who had received Address correspondence to R. Talanow ([email protected]) the lecture, (July through December, 2007) .

Background Information: Complex cancer staging systems Results: There was an overall reduction of 26% in the studies describe the anatomic spread of a particular malignancy . Staging ordered per discharge when comparing 2007 to 2006 (p<0 .001) . provides prognostic information and is vital in guiding appropri- There was a consistent decrease in CTs per discharge, averaging ate therapy . However staging can be difficult to perform for the a reduction of 18% over the study period . MRI and nuclear medi- inexperienced physician and inaccurate staging can lead to cine studies performed per discharge were also reduced 38% unnecessarily adverse patient’s outcome . The author provides a and 22%, respectively . Over the study period, 1101 advanced free, comprehensive, Web-based, on-the-fly solution which is imaging studies were ordered in a six-month period in 2006 by easy to use and aids in accurate staging of lymphoma . medical interns, compared to 827 in 2007 . The number of dis- charges from July to December in 2006 compared to 2007 was Educational Goals/Teaching Points: The goal is to create a not significantly different, 10,658 vs . 10,819, respectively . free, Web-based and customized lymphoma staging tool, which easily integrates into the radiologist’s daily work from any moni- Conclusion: Unnecessary advanced imaging of inpatients was tor or PACS station . significantly reduced by an easily replicated and cost-effective intervention of an informative lecture to the ordering physicians . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The tumor classification information is based on the Collaborative Staging Network . On-the-fly staging is done by cal- E097. Improving Cycle Time for Diagnostic Mammography: culating and comparing the information provided by the user Results from Mayo Clinic Quality Academy (CME Credit with the tumor classification database saved on the server . The Available) staging tool can be used in several modes for the user’s conven- Friese, J.; Maxwell, R.; Krecke, K.; Aakre, K. Mayo Clinic, Rochester, ience . Output of information is also offered in several modes to MN increase flexibility and better integration into the reader’s work- Address correspondence to J. Friese ([email protected]) flow . Objective: The goal is to show the significance of process Conclusion: This free, Web-based and customized program easi- improvement projects in improving patient care and satisfaction ly integrates into the radiologist’s daily work from any monitor or of diagnostic mammography patients and staff satisfaction . PACS station . The interface is flexible and easily adapts to the individual physician’s preferences by seamlessly incorporating Materials and Methods: A multidisciplinary team of physicians into the workflow . It is an intuitive, user friendly educational pro- and staff from breast imaging conducted a 100 day quality gram which makes staging of lymphoma easy and accurate . improvement project under the guidance of a quality advisor . Using the define, measure, analyze, improve, and control (DMAIC) framework, time studies were performed, patient and E096. Overutilization of Advanced Imaging in the Hospital staff surveys conducted, current and future value stream maps Setting: An Educational Approach to Reduce Unnecessary developed, and tests of change implemented . Inpatient Studies Platnick, J.; Voutsinas, L.; Wetz, R.; Madero, G.; Raden, M. Staten Results: Comprehensive value stream map and timing studies Island University Hospital, Staten Island, NY showed that 72 minutes were required for diagnostic mammog- Address correspondence to J. Platnick ([email protected]) raphy prior to implementation of process changes . Two process changes (i .e . tests of change) were undertaken . First, a technolo- Objective: The use of diagnostic imaging, particularly, advanced gist and radiologist were assigned to each patient who conduct- imaging including: CT, MRI and , for the diagno- ed the entire study from planning to interpretation . Second, sis and management of patients has been dramatically increas- imaging parameters were given the same day as the diagnostic ing . This study aimed to decrease the number of examinations mammogram rather than at the time of screening mammogra- ordered by medical interns through targeted education . phy . Exams going through a redo loop decreased from 17 to 7% for radiologists and from 32 to 20% for technologists . Materials and Methods: In our 703 bed, tertiary care center, Consolidation and elimination of process steps resulted in medical residents, under attending supervision, order the majori- decreased time in the department from 54 to 38 minutes . Patient ty of tests and treatments for inpatients . The medical interns satisfaction regarding wait time improved from 87 to 96% . were given a lecture by a senior radiologist at the outset of their Employee satisfaction related to communication improved from internship year in late June, 2007 . The conference, developed in 2 .95 to 4 .19 (out of five) . conjunction with the internal medicine program director, described the risks, benefits and alternatives of the various imag- Conclusion: Process improvement projects in radiology can yield ing modalities . The discussion emphasized the radiation exposure positive results despite small incremental changes . The value of of various modalities and the increasing costs related to unneces- mapping the process and including paraprofessional staff are par- sary imaging . The goal of the lecture was to educate the interns amount to success . While extra time and effort is necessary to about radiologic studies and their appropriate usage . The radiolo- participate in quality improvement projects, changes can yield gist emphasized the department’s availability to the medical staff benefits in patient and staff satisfaction .

209 El e c t r o n i c Ex h i b i t s : Efficacy, PACS

E098. Creating an Improved Radiology Resident: Techniques Educational Goals/Teaching Points: Twenty-eight Nobel to Help Detect Critical Findings (CME Credit Available) Laureates have made important discoveries or invented machines Gerard, P1; Lefkovitz, Z. 2; Moonthungal, S1. 1. Maimonides that have contributed significantly to the advancement of radiolo- Medical Center, Brooklyn, NY; 2. Mount Sinai Medical Center, gy . The majority (86%) are scientists and engineers . Most of the New York, NY Nobel Prize winners’ research was in the basic sciences . Only Address correspondence to P. Gerard ([email protected]) four (14%) of these individuals were physicians . In contrast, of the 175 laureates of the Nobel Prize in Physiology and Medicine, Background Information: The goal is to demonstrate a variety 54% were physicians . of visual and cognitive techniques to help enhance a radiology residents observational skills which can be applied to the every- Key Anatomic/Physiologic Issues and Imaging Findings/ day interpretation of plain films and imaging procedures . The Techniques: The revolution in radiology over the last three dec- result is enhanced observations, interpretation skills and perform- ades has occurred due to the invention of ultrasound, CT, PET ance, more accurate readings and ultimately better patient care . and MR scanners . The invention and advancement of these imag- ing techniques could not have been possible without key discov- Educational Goals/Teaching Points: Radiology residents are eries in physics, electrical engineering and computer technology . accepted into residency positions based on certain criteria includ- ing academic performance, without a well defined method of Conclusion: There is a historic bond between physics, engineer- evaluating the ability to assess and interpret radiographic studies, ing, and medicine in the advancement of medical knowledge . which have become increasingly more complex and demanding . Revolutionary progress in medicine requires synergy between the Lectures convey important information however may not physical and biological sciences . Therefore, while incremental enhance the ability to identify critical findings . We will display a advances within our field will continue, resources must be allo- pictorial of different visual techniques and exercises that will help cated to collaboration outside radiology to lay the groundwork train residents in increasing their observation skills . for future ground-breaking discoveries .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: We will demonstrate a variety of techniques and E100. Collaborative Radiology Resources: Radiopaedia.org exercises to help promote better observational skills . These have as an Example of a Web 2.0 Radiology Resource been utilized at our institution with better performance by resi- Gaillard, F. 1; Jones, J. 2 1. Vancouver General Hospital, dents . Techniques that will be included in our presentation Vancouver, Canada; 2. Leeds General Infirmary, Leeds,United include: use of images containing various scenarios for interpre- Kingdom tation, location of objects on films, use of corner signs in inter- Address correspondence to F. Gaillard ([email protected]) pretation, subliminal images, diagnosis on lateral projections, and a variety of other techniques will be demonstrated . Background Information: Radiopaedia org. is a free online radi- ology resource built and maintained by its users . The idea is to Conclusion: We have identified specific issues in resident obser- gather a small fraction of our collective knowledge in a single site vation and interpretation skills of plain films and imaging proce- which can act as a valuable digital reference . There are no sub- dures and have developed a series of visual techniques to help scription fees and no restrictive copyright–all material is available train radiology residents in enhancing cognitive and perceptual under the Creative Commons 3 .0 license . It is a true peer analysis skills . This can help prevent interpretation errors and sig- reviewed site–where errors can be found and corrected, discus- nificant misses . We hope that when applied during a radiology sion on difficult or controversial topics can be shared, and images resident’s training years, they can be helpful in enhancing a resi- submitted and used . It is basically like a specialist version of dent’s ability to detect important and critical findings and pro- Wikipedia, aimed at the radiology community . mote better patient care . Educational Goals/Teaching Points: The goal of this exhibit is to introduce Radiopaedia org. and how it works; review the fea- E099. Nobel Prize Winners Who Have Made Significant tures and purpose of Creative Commons Licenses (CCLs), and Contributions to Radiology outline how these features differ from those of traditional copy- Dunn, D.; Mansfield, L. Brooke Army Medical Center, San Antonio, right; give examples of how images (radiological images, as well TX as medical illustrations) can be licensed under CCLs and the ben- Address correspondence to L. Mansfield (liem_mansfield@ efits of CCLs over traditional copyright, and demonstrate how hotmail.com) small contributions by multiple users yields a comprehensive resource ideal to teaching and reference . Background Information: Nobel Laureates have made signifi- cant contributions to the establishment of radiology as an impor- Conclusion: Collaborative resources have been shown to work tant branch of medicine . Roentgen and the Curies are the most remarkably well in other settings . Radiopaedia .org offers a mech- obvious; their revolutionary discoveries formed the basis of diag- anism to generate a free and copyright free resource for radiolo- nostic radiology, radiation therapy and nuclear medicine . gy . Distributing radiology/medical images under Creative However, there have been others . The purpose of this education- Commons Licenses offers significant advantages to both the gen- al exhibit is to honor these Nobel Laureates and their ideas, eral radiology community, as well as the individual owner of the inventions and discoveries which laid the foundation of radiology material . The combination of user created content and Creative as we know it today . Commons Licenses is of great potential benefit to the whole radiological community .

210 El e c t r o n i c Ex h i b i t s : Efficacy, PACS

E101. Using “Hyperlinks” in PowerPoint Presentations as a brought up in the PACS system for end user review . This program Teaching Tool for Radiology Trainees–An Interactive Tutorial was made accessible to all users and was deployed to the radiol- (CME Credit Available) ogy residents and attendings in our department . Data collected Stacy, G.; Thiel, S. University of Chicago Medical Center, Chicago, included log of uses and subsequent work list generation . IL Address correspondence to G. Stacy ([email protected]) Results: The program has demonstrated its ability to reliably and quickly search through the entire hospital database of radiologi- Background Information: PowerPoint software (Microsoft, cal exams and generate work lists of exams based on user Redmond, Wash) has become a popular tool for creating and defined search parameters . Over a period of 27 days, 106 sepa- showing electronic presentations . Such presentations typically rate uses of the program have been documented . Examples of consist of a series of “slides” that are presented in sequential work lists generated have included acute epiglottis, neurofibroma order by a lecturer to his or her audience . The “hyperlink” func- and aortic dissection . These uses have occurred at all times of tion in PowerPoint, however, allows a user to advance from one the day and night . slide to any other slide in the presentation when he or she clicks on a pre-determined word or image . The hyperlink can also “con- Conclusion: With the use of the program, any user can, in real nect” the word or picture to a slide in a completely different time, generate a work list of cases that fit his/her specific clinical presentation, as well as a Web page, e-mail address, or another question . These cases can then be reviewed on the local PACS type of file . system, allowing “real world” manipulation of images . This proc- ess has been used at our program prior to uncommon proce- Educational Goals/Teaching Points: The goal of this exhibit is dures, such as elbow arthrograms, and also in generating exam- to showcase how the hyperlink function can enhance PowerPoint ples of important findings for residents on call to compare with presentations by making these presentations more interactive the case they are currently interpreting . For case conferences or and informative . For example, potential answers to a multiple- board review, instead of accessing online or pre-built case files, a choice question can each be linked to specific slides, providing user could generate a new work list of cases of recent, institu- instant feedback to the user . A similar process can be used to tional examples . As these cases are then displayed in the local create “games” in which a “contestant” can pick from a list of PACS, exams can be presented as unknowns and manipulated “categories”, each of which would be linked to a particular slide utilizing the standard PACS tools . For end of rotation in-service with a text- or image-based question . Hyperlinks can also be exams, instead of written questions or static images, actual PACS- made “invisible” and placed on an image, creating an education- centered cases can be used, allowing for realistic evaluation of al tool whereby the user would be instructed to “point” to a par- clinical performance . ticular anatomic structure or pathologic process with appropriate feedback . Links to other documents or Websites can also be cre- ated, providing additional detail regarding a particular disease E103. Thin Client Servers: Technical Aspects, Applications, process, if desired by the user . This exhibit will provide an inter- Advantages and Limitations (CME Credit Available) active tutorial which demonstrates the necessary steps to create Jagtiani, M.1; Kalra, M.1; Dreyer, K.1; Schirmacher, H.2; Sack, D.1; such presentations . Saini, S.1 1. Massachusetts General Hospital, Boston, MA; 2. No Institutional Affiliation Conclusion: The use of hyperlinks in PowerPoint presentations Address correspondence to M. Jagtiani Sangwaiya (mjagtiani@ allows for a much more dynamic and interactive educational partners.org) experience than can be obtained with serial presentation of slides alone . Background Information: Routine interpretation of digital radi- ology imaging is adequate on PACS workstations . However, many conventional PACS lack advanced postprocessing 3D and 4D E102. A Radiology Information System Search-Based viewing, reconstruction abilities and remote access . In these cir- Approach to Rare Case Interpretation cumstances, Web-based thin client servers can help, with not Green, A.; Kowal, D.; Garg, N. St Vincent, Worcester, MA only routine radiology image interpretation, but can also provide Address correspondence to A. Green ([email protected]) interactive 3D and 4D reconstruction .

Objective: This exhibit will discuss rapid and real time automatic Educational Goals/Teaching Points: A thin client is software in work list generation from a full text radiology information service client-server architecture networks which depends primarily on (RIS) as a reference resource for uncommon diagnostic cases the central server for processing activities, and mainly focuses on and procedures, on call comparison cases, and end of resident conveying input and output between the user and the remote rotation unknown exams . server . Recently thin clients have become available as fast view- ers for 2D, 3D, and 4D images . The purpose of this exhibit is to Materials and Methods: The development of this program highlight the technical aspects, advantages, and limitations for a involved the creation of a Wizard in our PACS system . This Wizard thin client based radiology image interpretation and 3D recon- initiated a Google desktop based search of the RIS database struction . using methods published by Erinjeri (Erinjeri 2008: Development of a Google-Based Search Engine for Data Mining Radiology Key Anatomic/Physiologic Issues and Imaging Findings/ Reports; Journal of Digital Imaging) . AJAX search results were Techniques: This exhibit will outline the technical aspects and then mined for relevant exam accession numbers . A custom work fundamentals of thin client Web-based PACS and describe the list was then automatically generated using auto hotkey string differences between thin client based PACS and conventional processing, thus enabling the list of pertinent exams to be PACS, advantages of thin client based PACS with suitable exam-

211 El e c t r o n i c Ex h i b i t s : Efficacy, PACS ples from different radiology subspecialties (for example, in E105. Integrating PACS and the Hospital Information System emergency, chest and abdominal imaging) and current limita- Using Open Source Software (CME Credit Available) tions of both Web and conventional PACS with appropriate clini- Gentili, A.1,2 1. VA San Diego Healthcare System, San Diego, CA; cal examples . 2. University of California, San Diego,, San Diego, CA Address correspondence to A. Gentili ([email protected]) Conclusion: This exhibit describes the technical aspects and fun- damentals of thin client servers in modern day radiology practice Background Information: Referring physicians often provide with help of suitable radiology examinations . A thin client may incomplete clinical history on radiology requests . Having better help off-lying radiology interpretation from conventional PACS in clinical histories improve the ability of radiologists to provide bet- daily radiology practice . ter interpretations and make correct diagnosis . Often more clini- cal information is available in the Hospital Information System (HIS), but in most cases the patient records in HIS are not availa- E104. How to Select the Best PACS Solution for Your ble from PACS . Integrating PACS and HIS is technically possible, Institution as most modern PACS and HIS systems can communicate using Dang, P.; Kalra, M.; Sack, D.; Schweitzer, A.; Dreyer, K. HL-7, but it is often not easy to do, and requires a knowledge of Massachusetts General Hospital, Boston, MA both systems and cooperation of both manufacturers . We have Address correspondence to P. Dang ([email protected], used an open source program, AutoHotkey, to synchronize the [email protected]) HIS client application, with the patient displayed on PACS on the client machine . Background Information: The advent of PACS has resulted in improving the workflow, workload, and productivity of radiology Educational Goals/Teaching Points: AutoHotkey is a free, departments and the healthcare enterprise as a whole . Given the open-source utility for Windows . With AutoHotkey, it is possible multiple PACS options available, choosing a vendor can be diffi- to automate almost any program by sending keystrokes and cult . mouse clicks . With this program, it is possible to write a macro that can be compiled into a small executable file that can be run Educational Goals/Teaching Points: PACS enables easy availa- from any directory without any need for installation, or registry bility of digital images virtually on all clinical workstations modification . We have created a simple macro to synchronize HIS throughout the healthcare institution, which helps to improve the with PACS . Radiologists, while working on PACS, at the press of a workflow, report turn around time, productivity, and clinical care . shortcut key, can activate this macro . The macro opens the HIS A careful selection of the type of PACS solution should be based client, if not already running, once the HIS client is running, and on the institution’s demands, workflow, and infrastructure . the radiologist is logged in, the macro transfer the hospital Successful selection of the PACS vendor involves making an number of the current patient from the PACS display window appropriate needs assessment plan, identifying the critical stake- into the HIS client, simulating the keyboard, to display the holders, writing an effective request for proposal, making com- patient’s medical records . This is all done using Windows func- prehensive site visits and effectively negotiating the terms and tions, without the need to know about HL-7 or how the PACS conditions . The exhibit will include steps for PACS vendor selec- and HIS function . tion, including: A) Developing an appropriate business plan: 1 . Perform a cost-benefit analysis considering various factors such Key Anatomic/Physiologic Issues and Imaging Findings/ as dollars saved, liabilities, improved workflow, decreased work- Techniques: This macro facilitates reviewing the patient clinical load, and improved patient care . 2 . Develop a strategic business history and has increased the frequency with which radiologists plan to survey the facility, the existing resources and infrastruc- review the patient medical records . This method has several ture, and the views of the administration and critical stakehold- advantages; it is free, works with PACS and HIS of different man- ers . 3 . Determine a clear set of goals and key objectives for PACS ufacturers and does not require complex installations . A limita- implementation . 4 . Define the principle criteria for evaluating the tion of this approach is that works only on Windows based sys- different vendors . B) Writing an effective request for proposal tems . (RFP) should include goals and objectives of the institution; information on the health care enterprise and radiology depart- Conclusion: Using Autohotkey, it is possible to synchronize PACS ment including general information and specific information and HIS, and have HIS display the clinical history of the patient about: operations, workflow, workload, hardware and software displayed on PACS . requirements for acquiring, archiving and viewing of images, net- working requirements, and training requirements, and other requirements such as maintenance, security, support, warranties, E106. An Overview of the Economics of Radiology (CME image and data management, timelines, financial terms, and pay- Credit Available) ment options . It will also provide details on reviewing responses Liu, R. New York Presbyterian Hospital, New York, NY to the RFP, performing detailed site visits, negotiating the con- Address correspondence to R. Liu ([email protected]) tract and tallying the return of investment in spreadsheets, graphs, and figures . Background Information: The economics of radiology repre- sents a broad field, with multiple levels of complexity . Traditional Conclusion: Choosing an appropriate PACS vendor that meets training of radiologists offers limited education in this increasingly the requirements for an institution is very important to realize the important facet of radiology . This exhibit aims to offer an initial true benefits from PACS implementation and avoid the unneces- perspective of the economics of radiology, introducing the audi- sary costs and expenses . This exhibit describes the steps for suc- ence to fundamental concepts that can help facilitate a deeper cessful selection of a PACS vendor . understanding of the field .

212 El e c t r o n i c Ex h i b i t s : General, Emergency

Educational Goals/Teaching Points: The exhibit offers three studies not necessarily related to the initial study are presented . major areas of conceptual learning, including 1) an understand- Subtle examples on CT that may aid the reader in identifying ing of the current economic landscape in radiology 2) an over- ischemia with MR correlation are presented . Target areas of view of the revenue stream of a radiology practice and 3) how errors in breast imaging are presented . Cancers in dense breasts the convergence of macroeconomic and microeconomic factors and the edge of the film are presented . Communication strate- are affecting the current radiology employment market in both gies are presented designed to reduce misunderstanding . academic and private practice settings . Conclusion: Radiology is a high malpractice specialty in both Key Anatomic/Physiologic Issues and Imaging Findings/ number of claims and payment/claim compared to other special- Techniques: An examination of the current economic landscape ties . The majority of radiology malpractice claims were related to will take a broad view of the historic relationship of the role of the breast and brain . We present strategies through examples in imaging within the national health care system . Further analysis image interpretation to provide a vehicle for improvement to focuses on recent trends in imaging costs, with an emphasis on reduce malpractice risk . understanding how differences in modality and specialty affect procedure volume and spending . In addition, the major current disruptive forces which are changing the field of radiology are examined, utilizing the economics of teleradiology as a case Ge n e r a l , Em e r ge n c y study . The overview of the revenue stream of a radiologist is accomplished by focusing on the history of the Medicare pay- E108. An Assessment of Ordering Physician’s Knowledge ment system, with a flow chart analysis of key criteria necessary and Attitudes Regarding Risk from CT Associated Radiation for successful revenue generation by a radiology practice . Finally, Exposure (CME Credit Available) 1 2 3 the employment market is reviewed over a ten-year period, with McBride, J. ; Paxton, B. ; Wardrop, R. 1. Mayo Clinic–Rochester, current differences in subspecialty and practice model variances Rochester, MN; 2. Duke University, Durham, NC; 3. Carilion Clinic, highlighted . Roanoke, VA Address correspondence to J. McBride (mcbride.jeremy@mayo. Conclusion: While the economics of radiology is a multilayered edu) complex field, an initial overview serves the purpose of introduc- ing key concepts that can serve as a springboard for a more com- Objective: Medical literature suggests that ionizing radiation prehensive education on this increasingly critical aspect of the from CT can significantly alter a patient’s lifetime attributable risk radiology practice . of developing neoplasms . It is our hypothesis that ordering physi- cians have limited knowledge of CT-related radiation expo- sure with its associated risks . E107. Radiology Malpractice: An Illustrated Presentation of the Problem and Possible Solutions to Reduce Risk (CME Materials and Methods: An internet-based, anonymous survey Credit Available) was sent to the ordering physicians of a regional tertiary care Tu, R.; Kori, G.; Zeman, R.; Akin, E.; Kambhampati, S. George teaching hospital . The survey was designed to evaluate their Washington University, Washington, DC knowledge, attitudes and self-assessed practice behaviors as Address correspondence to R. Tu ([email protected]) related to the potential increased risk of cancer from CT-related radiation exposure . Both faculty and residents were invited to Background Information: The purpose of this study was to respond to the survey . Complete and incomplete surveys were illustrate examples of malpractice risk . We reviewed malpractice included . cumulative and indemnity data from 2002-2007 . We ana- lyzed malpractice in all reported medical specialties in compari- Results: Respondents to the survey were primarily faculty (63%) son to radiology . Examples of risk are presented as an opportuni- and the largest represented specialty was internal medicine ty for improvement . (43%) . When asked to rate a list of factors as influential when ordering CT scans, 100% responded that the ability of CT to rule Educational Goals/Teaching Points: A review of claims and in/rule out a diagnosis was influential and 85% reported that the indemnity data from the Physicians Insurance Association of speed and ease with which a clinical answer could be obtained America from 2002-2007 was completed . Radiology had a dis- influenced their decision . A total of 46% reported that the poten- proportionate high number of claims . The categories of high radi- tial risk of litigation from not ordering the exam was influen- ology malpractice claims were reviewed . Brain and diseases of tial . Concern regarding the radiation exposure from the exam and the breast were the majority of malpractice claims . Issues of the cumulative radiation that a patient had received from prior communication were also cited in the claims . Examples of the exams influenced only a minority of respondents, 22% and 19% subtle and not so subtle brain lesions and breast lesions are pre- respectively . When asked to identify the equivalent radiation sented so the reader may gain insight to reduce misinterpreta- exposure a CT scan represents, in plain radiographs 64% under- tion . Communication strategies are also provided to help reduce estimated . When asked if the lifetime risk for developing cancer misunderstands and escalation to a malpractice event . from one pediatric CT scan was increased, 75% reported affirma- tively and 26% correctly identified the estimated risk; 58% Key Anatomic/Physiologic Issues and Imaging Findings/ believed the same to be true in adults; 59% of respondents Techniques: Target regions of errors in brain imaging interpreta- admitted that they do NOT discuss the potential risks of CT with tion are illustrated . Typical problematic regions of the cerebral patients and only 20% discuss the risk of radiation specifically . convexity, inferior frontal lobe and fourth ventricle are illustrated . Postsurvey free text comments included many admissions of The skull base and infratemporal fossa lesions in cranial imaging ignorance and a desire to “know the answers ”.

213 El e c t r o n i c Ex h i b i t s : General, Emergency

Conclusion: Physicians who order CT scans have limited knowl- ing image quality while minimizing radiation risk will vary edge of the impact of ionizing radiation exposure and its poten- between machines depending on detector number . tial for increasing cancer risk in patients . Our results suggest that radiation education for ordering physicians is needed and would likely be welcomed by most . Radiologists have an opportunity to E110. Safety of the Gadolinium Chelates (CME Credit positively impact patient care by educating ordering physicians of Available) the potential risks of ionizing radiation and providing consultation Runge, V. Scott and White Clinic and Hospital, Temple, TX on appropriate alternative imaging . Address correspondence to V. Runge ([email protected])

Background Information: Magnetic resonance contrast agents, E109. Determining Fetal Radiation Dose on 4-, 16- and specifically the gadolinium chelates, are very safe and lack the 64-Slice CT Scanners for Pulmonary Angiograms and nephrotoxicity (when injected intravenously) associated with Abdomen Examinations Throughout Pregnancy (CME Credit iodinated contrast media . Minor adverse reactions occur infre- Available) quently and include nausea, taste perversion, and hives . Whereas Gilet, A.; Dunkin, J.; Fernandez, T.; Moore, W.; Budorick, N. SUNY these agents cannot be differentiated on the basis of mild Stony Brook University Medical Center, Stony Brook, NY adverse effects, they do differ in regard to chelate stability, with Address correspondence to A. Gilet ([email protected]) clinical lab abnormalities known with the less stable agents . The issue of nephrogenic systemic fibrosis (NSF) and its relationship Objective: The objective was to determine an estimated dose to the gadolinium chelates (and specifically their in vivo stability) range for fetal exposure during four different stages of pregnancy have drawn widespread attention in the last two years to the for both computed tomographic (CT) pulmonary angiogram and subject of safety of these agents . These topics are discussed in CT abdomen/pelvis examinations on a 4-, 16- and 64-slice CT depth in this educational exhibit, together with current updates scanner . and recommendations for clinical practice .

Materials and Methods: Simulated pulmonary angiograms and Educational Goals/Teaching Points: The educational goals are abdomen/pelvic studies were performed on an anthropomorphic to discuss the clinical safety of the gadolinium chelates, as con- phantom on 4-, 16- and 64-detector CT scanners using both con- trast media for MRI and provide a basis of knowledge upon sistent parameters and current institutional standard protocols for which appropriate guidelines for clinical use can be drawn, and abdominal and pelvic imaging of pregnant patients . Different appropriate differentiation made between the approved agents . stages of pregnancy were reproduced by adding soft tissue equivalent material (TX151) to create a pregnant phantom Key Anatomic/Physiologic Issues and Imaging Findings/ model . Fetal positioning and mean fetal depth were determined Techniques: Topics to be discussed include: minor adverse reac- using previously published data from ultrasound examinations of tions and their incidence (nausea, hives); severe anaphylactoid a large cohort of patients . Thermoluminescent dosimeters (TLDs) reactions; physicochemical characteristics; stability – thermody- were placed at appropriate positions for different gestational namic and kinetic; transmetallation/dechelation; interference ages . Scans were performed for early pregnancy, ten, 18 and 36 with laboratory tests (in particular serum calcium), and nephro- weeks gestational age fetal doses and entrance skin exposure genic systemic fibrosis – origin, incidence, prevention . were measured . Effective dose was calculated using International Commission on Radiological Protection methods . These were Conclusion: The gadolinium chelates, widely used in MR clinical compared with the dose–length product (DLP) and CT dose practice, are in general a very safe class of contrast media . The index (CTDI) that were generated by the scanners . safety basis of these agents rests fundamentally with the stability of the metal chelate in the body and rapid excretion . Knowledge Results: When using constant parameters for CT pulmonary ang- of NSF has led to re-examination of this topic, with the trend in iograms we found the fetal radiation dose was not significantly utilization being toward the more stable chelates and the likely associated with gestational age . For the 4-, 16- and 64-detector long-term outcome being the withdrawal of several agents from scanners the fetal dose averaged .063 cGy and the 16-slice scan- clinical use . ner was the most dose efficient (average dose .044 cGy) . For CT abdomen we found the highest radiation dose was recorded in early pregnancy; this was 1 15. cGy, 0 99. cGy and 1 56. cGy on the E111. Role of an Advanced Statistical Iterative 4-, 16- and 64-slice scanners respectively . There was an average Reconstruction Technique for Improving the Image Quality 20% higher radiation dose to the fetus with all three scanners of Low Radiation Dose CT (CME Credit Available) then was measured at the anterior abdomen skin entry Singh, S.1; Jagtiani, M.1; Blake, M.1; Thomas, S.1; Joshi, M.2; site which underestimates fetal exposure . When scanning param- Kalra, M.1 1. Massachusetts General Hospital, Boston, MA; 2. eters were kept constant between machines gestational age and General Electric Company, Giles, United Kingdom fetal dose were not significantly related, however when the insti- Address correspondence to S. Singh ([email protected]) tutional protocols (manufacturer recommended) for pregnant patients were used the dose was significantly higher in the third Background Information: In current CT scanners, images are trimester on the 64-slice scanner . reconstructed using filtered back projection reconstruction algo- rithm . Filtered back projection techniques have higher image Conclusion: Radiation doses to a fetus for pulmonary angi- noise, streak artifacts as well as beam hardening artifacts . Image ograms with shielded abdomen and abdominal CTs are higher reconstruction algorithms such as iterative reconstruction help to than what has been reported in the earlier literature performed improve image quality of low dose CT examinations, as these on single slice scanners . Optimal parameters for maximiz- reconstruction techniques have much lower image noise .

214 El e c t r o n i c Ex h i b i t s : General, Emergency

Educational Goals/Teaching Points: This exhibit will describe Conclusion: Many benign lesions may mimic neoplasia both the implications of low dose CT images on image noise and clinically as well as on radiologic imaging . These can involve diagnostic acceptability with filtered back projection reconstruc- diverse anatomical sites . A high index of suspicion for these tion technique; the effect of advanced statistical iterative recon- pathologies in the correct clinical context and correct interpreta- struction (ASIR) (GE Healthcare, Milwaukee, WI) technique on tion by using characteristic radiological findings may lead us to low dose CT data reconstruction; the fundamental basics of itera- the correct diagnosis and help avoid unnecessary anxiety, incor- tive image reconstruction techniques, and CT dose reduction with rect treatment and surgical procedures . advanced statistical iterative reconstruction in different body regions . E113. Abdominal Manifestations of Cystic Fibrosis as Seen Key Anatomic/Physiologic Issues and Imaging Findings/ on MDCT: A Pictorial Review (CME Credit Available) Techniques: The exhibit will focus on the fundamental basics of Morgan, J.; Gupta, S.; Sadler, M. St. Vincent’s Hospital and ASIR of CT image reconstruction; the difference between ASIR Medical Center, New York, NY and filtered back projection reconstruction techniques; the effect Address correspondence to J. Morgan ([email protected]) of advanced statistical iterative reconstruction on image quality of low dose CT images; the use of ASIR to reduce radiation dose Background Information: Cystic fibrosis is an inherited auto- with CT in different body regions, and the application of ASIR in somal recessive condition that has multiple well-identified pul- clinical scanners or clinical image reconstruction with suitable monary manifestations . Radiologists should also be well-familiar examples and illustrations . with manifestations seen in the abdomen, some of which have serious implications . As the life-expectancy of individuals with Conclusion: This exhibit describes the role of ASIR to improve cystic fibrosis continues to increase, it is important for these the image quality of low radiation dose CT examination by reduc- abdominal manifestations to be recognized and promptly man- ing image noise and thus making them diagnostically acceptable . aged in order to achieve optimization of the patient’s overall well-being and health .

E112. Benign Mimics of Neoplasia. Can We Avoid a Wrong Educational Goals/Teaching Points: The goal is to highlight the Diagnosis? List of the Uncommon Lesions and Findings various manifestations of cystic fibrosis in the abdomen, includ- Misdiagnosed as Malignancies ing the hepatobiliary system, gastrointestinal tract and genitouri- Choudhary, S.; Restrepo, C.; Prasad, S.; Chintapalli, K. University nary system; illustrate the imaging findings associated with these of Texas Health Science Center–San Antonio, TX manifestations, including typical and atypical features, and pro- Address correspondence to S. Choudhary ([email protected]) vide the viewer with a basic understanding of cystic fibrosis in the abdomen and the ability to appropriately convey relevant Background Information: Multiple benign imaging findings and findings to the referring physician . lesions may mimic malignancy on imaging and lead to unneces- sary surgery, biopsy and patient anxiety . The most commonly Key Anatomic/Physiologic Issues and Imaging Findings/ described lesion in this category is the inflammatory pseudotu- Techniques: Abdominal manifestations will be discussed and mor which consists of a proliferation of plasma cells and other grouped according to system, and MDCT findings will be demon- inflammatory cells, a fibrous stroma, and spindle cells that are strated as follows: Hepatobiliary System: hepatic steatosis, gall- sometimes associated with a granulomatous reaction . This entity, bladder and biliary system pathology, cirrhosis; Pancreas: fatty which has the gross appearance of a malignant tumor but has a replacement, calcifications, acute pancreatitis, neoplastic condi- benign histological appearance and course, has been found in tions; Gastrointestinal Tract: gastroesophageal reflux, peptic ulcer many locations . Most frequently found in the lung, inflammatory disease, distal intestinal obstruction syndrome (DIOS), intussus- pseudotumors also have been reported in the stomach, retroperi- ception, appendicitis, malignancies, pseudomembranous colitis, toneum, orbit, and central nervous system . However there are and Renal: nephrolithiasis . multiple other benign lesions that may mimic a malignant tumor radiologically and misdiagnosed . These lesions not only mimic Conclusion: As the lifespan of patients with cystic fibrosis malignant tumors radiologically but also clinically . The radiologist increase, extrapulmonary manifestations are now more prevalent . should be well aware and acquainted with these entities to help With the advent of MDCT, more patients undergo abdominal avoid improper management . imaging for complaints such as abdominal pain or abnormal liver function tests . It is important for radiologists to recognize the Educational Goals/Teaching Points: In this pictorial essay, a manifestations of abdominal cystic fibrosis and to then convey selection of inflammatory pseudotumors and their imaging find- these findings, allowing for appropriate intervention as necessary ings are discussed . Multiple other lesions/imaging findings that may be incorrectly diagnosed as malignancy in multiple locations and their characteristic radiological features are illustrated . A E114. The “Six Pack” in Black and White. Imaging Review of review of the radiological features that may assist in the correct the Rectus Abdominus interpretation of the benign nature are discussed . Chaudhary H.1; Choudhary, S.2; Fasih, N.1; Sunnapwar, A.2 1. The Ottawa Hospital, Ontario, Canada; 2. University of Texas Key Anatomic/Physiologic Issues and Imaging Findings/ Health Science Center–San Antonio, TX Techniques: The purpose of this exhibit is to illustrate multiple Address correspondence to S. Choudhary ([email protected]) benign pathologies including the inflammatory pseudotumor that mimic neoplasms on imaging . Background Information: The rectus abdominis is a paired pos- tural muscle of the anterior abdominal wall separated by a mid-

215 El e c t r o n i c Ex h i b i t s : General, Emergency line band of connective tissue called the linea alba . It extends Educational Goals/Teaching Points: After viewing this exhibit, from the pubic symphysis inferiorly to the xiphisternum and radiologists will recognize active bleeding and pseudoaneurysm lower costal cartilages . It is enclosed within the rectus sheath, on MDCT and CDI in a variety of clinical scenarios; differentiate except below the arcuate line where it is separated from the per- active vascular contrast extravasation from pseudoaneurym, and itoneum only by the transversalis fascia . The rectus muscle can understand clinical management of active bleeding and pseu- be involved by diverse disease processes, including infection, doaneurysm . tumor both primary and secondary, and hemorrhage . Multiple unusual lesions affecting the muscle such as lipoma and Key Anatomic/Physiologic Issues and Imaging Findings/ endometriomas are also described . Inferior to the arcuate line, Techniques: This exhibit will review the literature concerning the the area is also more susceptible to herniation . Spigelian hernia imaging signs of active hemorrhage and pseudoaneurysm; is an acquired ventral hernia through the linea semilunaris . The describe the imaging features of active hemorrhage and pseu- close proximity of the epigastric artery is the usual suspect for doaneurysm on contrast-enhanced MDCT and color Doppler cases with spontaneous and postprocedural active bleeding and ultrasound in a variety of clinical conditions including iatrogenic hematomas . instrumentation, anticoagulation, vascular disease, spontaneous, acute gastrointestinal and neoplasia, and discuss clinical manage- Educational Goals/Teaching Points: This exhibit will describe ment of active hemorrhage and pseudoaneurysm with descrip- the essential anatomy of the rectus abdominis and the rectus tion of noninvasive therapies including embolotherapy and ultra- sheath; describe the common pathologies involving this compart- sound guided compression . ment and their imaging features on multiple modalities including ultrasound, CT and MRI, and describe an algorithmic approach Conclusion: This educational exhibit reviews the MDCT and CDI for correct diagnosis using imaging and percutaneous biopsy in appearance of active bleeding and pseudoaneurysm in a variety equivocal cases . of conditions including trauma, iatrogenic instrumentation, anti- coagulation, and pancreatitis, and reviews the appropriate clinical Key Anatomic/Physiologic Issues and Imaging Findings/ management of such cases . Techniques: Ultrasound as well as CT provides a noninvasive way of visualizing the presence and extent of diseases involving the rectus abdominis . MR imaging is a helpful adjunct however should E116. Dose Preoperative Localization of the Appendix using be used selectively . The imaging features of infection, tumor, and 3D CT Affect on the Incision of Choice from the McBurney’s hemorrhage may be similar however accurate diagnosis can be Point in Acute Appendicitis? (CME Credit Available) achieved with a thorough knowledge of the anatomy, pertinent Bae, K.; Jeon, K.; Hong, S. Gyeongsang National University clinical data and imaging features . In equivocal cases, ultrasound Hospital, Jinju, South Korea can be used to guide biopsy and drainage procedures . Address correspondence to K. Bae ([email protected])

Conclusion: Knowledge of the normal anatomy of the rectus Objective: The aim of this prospective study was to determine abdominis muscle and the rectus sheath is important for the the site of appendix using preoperative 3D CT and to examine diagnostic radiologist because of the associated clinical rele- the usefulness of this 3D CT information on a surgeon’s choice of vance . These muscles are also affected by diverse conditions with incision for appendectomy . a spectrum of imaging features . A systematic approach helps in reaching a reasonable diagnosis . Materials and Methods: After exclusion of all patients with complicated appendicitis or previous intra-abdominal surgery, the study population included 100 consecutive patients who under- E115. Lines and Circles: Cross-Sectional Imaging of Active went appendectomy during 2006 . Volume rendering reconstruc- Bleeding and Pseudoaneurysms (CME Credit Available) tion of the MDCT data using 3D software was performed for each Choudkary, S.1,2; Fraser-Hill, M.1 1. The Ottawa Hospital, Ottawa, patient before surgery . The location of the base of the appendix Canada; 2. University of Texas Health Science Center – San and the McBurney’s point were marked on a single 3D image Antonio, TX that allowed the skin surface to be displayed . The distance Address correspondence to S. Choudhary ([email protected]) between the base of the appendix and the Mc Burney’s point was measured . The surgeons performed appendectomies with Background Information: In 1989, the “sentinel clot sign” was the 3D CT information and measured the length of the incision recognized as an accurate indication of hemorrhage from and the distance between the surgical incision and the abdominal organs . Modern imaging techniques including MDCT McBurney’s point . and color Doppler imaging (CDI) permit accurate recognition of potentially life-threatening active hemorrhage and pseudoaneu- Results: The mean distance between the base of the appendix rysm which occur when vascular integrity is breached . While and the McBurney’s point was 2 7. cm on 3D CT . The appendix active hemorrhage is uncontained, pseudoaneurysms are at least base was located within 1 cm from the McBurney’s point in 18% temporarily contained by a false wall . Most reported cases of of the patients . The appendix was within 3 cm and 5 cm from imaging-detected active hemorrhage occur in the setting of trau- the McBurney’s point in 64% and 86% of patients, respectively . ma . Other causes include iatrogenic instrumentation, anticoagula- During the operation, the surgeons altered incision site from the tion, aortic disease, and neoplasia . Clinical management depends McBurney’s point in 33% of the patients . The distance between on patient factors, the cause, location and extent of bleeding and the center of the incision and the McBurney’s point was more comprises several therapeutic options including conservative than 3 cm in 8% of the patients . management, ultrasound-guided compression, angiographic embolization and surgery .

216 El e c t r o n i c Ex h i b i t s : General, Emergency

Conclusion: Since the location of the appendix base has a wide Materials and Methods: This is a four year review from 2004 to individual variation, the McBurney’s point has a limited use as a 2008 of 124 cases of acute abdomen from the emergency surgical landmark for an appendectomy . The localization of the department who had CT scans of the abdomen and pelvis . All appendix using 3D CT will provide useful information to surgeons these patients were scanned with 5 mm thick slices at 5 mm and enable them to make a precise and minimal incision during intervals initially and subsequently reconstructed at 2 mm thick an appendectomy . slices at 1 mm intervals from the original data and multiplanar reconstructions are generated by the radiologist at a separate workstation . The clinical indications included right lower quadrant E117. “Where is the Air?” Pattern Recognition on Abdominal pain, left lower quadrant pain, bowel obstruction, and renal colic Plain Films: A Lost Art (CME Credit Available) and diffuse abdominal pain without localization . There were 84 Chandrasekhar, C1; Hancock, J. 1; Guthrie, A. 2 1. University of female patients and 40 male patients with ages ranging from 18 Texas Health Science Center Houston, Houston, TX; 2. LBJ years to 85 years . General Hospital, Houston, TX Address correspondence to A. Chandrasekhar (chitra.chan- Results: Multiplanar reconstruction images were able to identify [email protected]) the appendix in its entirety and differentiate it from small bowel and other adnexal structures, identify the transition zone defini- Background Information: The abdominal series still remains a tively in small and large bowel obstruction, identify the cause of fast and reliable method of evaluating the abdomen . It provides bowel obstruction, display any associated abnormality of the a roadmap in establishing the etiology of abdominal pain prior to mesenteric vessels, display associated pneumatosis intestinalis a CT scan . With the advent of modern techniques for evaluation and differentiate from pseudopneumatosis, abdominal hernias of the acute abdomen, recognition of classic abnormal air pat- and associated complications, adnexal abnormalities such as terns on abdominal series has fallen by the wayside . tubo-ovarian mass lesions and ovarian vein thrombosis .

Educational Goals/Teaching Points: The goals are to demon- Conclusion: Multiplanar reconstruction of the CT images is a strate classic plain film signs of abnormal gas patterns in the simple and useful technique and aids the radiologist in arriving at diagnosis of abdominal pain; review the plain film features of a confident diagnosis in most of the patients with acute abdo- free intra- and retroperitoneal air, air fluid levels, small and large men . bowel obstruction, ischemia, pneumobilia and infection on abdominal series, and to correlate with findings on abdominal CT where possible . E119. MDCT in the Evaluation of Extraperitoneal Pelvis for Blunt and Penetrating Trauma: Review of Anatomy and Key Anatomic/Physiologic Issues and Imaging Findings/ Tomographic Findings Techniques: A plain film of the abdomen provides a template Ballester, G.; Cortes, C.; Garcia, L.; Gomez, A.; Colon, E.; Lopez- that can help to identify an abnormal air pattern prior to a CT Alvarez, Y.; Alvarado, E. University of Puerto Rico, Guaynabo, PR evaluation . An abdominal series provides valuable information as Address correspondence to G. Ballester (goryballester@gmail. to the presence of free intra- or retroperitoneal air . It can also com) determine the presence of small or large bowel obstruction, air fluid levels, pneumobilia or the presence of intramural air in Background Information: Trauma related injuries are common bowel loops as well as in the gall bladder or urinary bladder . and are the leading cause of death and disability among the ages of one to 44 years . It is estimated that 150,000 people die each Conclusion: In spite of more sophisticated methods of evalua- year as a result of such injuries . Pertaining to pelvic trauma, there tion of abdominal pain, a plain film of the abdomen or abdomi- are usually two major categories: blunt and penetrating . Blunt nal series can contribute towards making a definitive diagnosis to pelvic trauma is usually related to motor vehicle collisions, determine the underlying cause of abdominal pain . The art of assaults, recreational accidents, or falls . Penetrating pelvic trauma plain film diagnosis is gradually being effaced out by other meth- is commonly related to gun shot wounds and stab wounds odologies . Recognition of key findings on an abdomen series still (homicides or suicides) . For the surgeon, the precise localization plays a crucial role in evaluating the acute abdomen . of the injury is vital and will dictate further management deci- sions . Nowadays, MDCT with multiplanar reconstructions (MPR) allows for better delimitation of the peritoneal and extraperito- E118. Impact of Multiplanar Reconstruction of CT Images in neal compartments . The radiologist should have a thorough the Evaluation of Acute Abdomen (CME Credit Available) knowledge of the complex anatomy of the extraperitoneal pelvic Malaty, R.; Hadley, W.; Paspulati, R. Case Western Reserve spaces in order to accurately describe and localize the extension University, Solon, OH of the injury . Address correspondence to R. Paspulati ([email protected]) Educational Goals/Teaching Points: The major teaching points Objective: The objective was to assess the efficacy of usefulness of this exhibit are to review the normal anatomy of the extraperi- of multiplanar reconstruction of CT of the abdomen in patients toneal pelvic spaces; to understand the value of MDCT in depict- with acute abdomen; discuss the technique of multiplanar recon- ing these spaces in pelvic trauma; to differentiate intraperitoneal struction of CT images in the evaluation of acute abdomen, and from extraperitoneal injuries in pelvic trauma, and to emphasize illustrate various examples, where multiplanar reconstruction has the importance of accurate compartment localization in patient helped in arriving at a diagnosis in patients with acute abdomen . treatment (i .e . surgical vs . conservative management) .

217 El e c t r o n i c Ex h i b i t s : General, Emergency

Key Anatomic/Physiologic Issues and Imaging Findings/ E123. Retroperitoneal Infectious Processes: A Pictorial Review Techniques: This exhibit will review the anatomy of the extra- Arnold, G.1; Jafri, Z.1; Werder, G.1; Amendola, M.2; Francis, I.3; peritoneal pelvic spaces, which includes the following: prevesical Amin, M.1 1. William Beaumont Hospital, Royal Oak, MI; 2. space, including retropubic retzius space; perivesical space; pre- University of Miami, Coral Gables, FL; 3. University of Michigan, sacral space; femoral vascular sheath space; perirectal space; Ann Arbor, MI ischiorectal space; ischioanal space, and pelvic sidewall . We will Address correspondence to G. Arnold ([email protected]) present case examples from our trauma level 1 institution to highlight findings along the previously described anatomical com- Background Information: The purpose of this exhibit is to partments . We will discuss common pitfalls of interpretation . describe the basic anatomy of the retroperitoneum and to illus- trate some of the infectious processes which occur there . Conclusion: Trauma is the leading cause of mortality and mor- bidity in the young population . The radiologist plays an important Educational Goals/Teaching Points: Specific examples of retro- role in the evaluation of patients with pelvic trauma . It is impera- peritoneal infectious processes illustrated include mycobacterium tive for the radiologist to have a thorough knowledge of the tuberculosis (TB), histoplasmosis, mycobacterium avium-intracel- anatomy of the extraperitoneal pelvic spaces since it can have lulare (MAI), xanthogranulomatous pyelonephritis (XGP), diver- significant impact on patient care . ticulitis with psoas abscess, discitis, mycotic aneurysm (aortitis), and brucellosis .

E121. Imaging Ventral Hernias: Anatomy, Surgical Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques and Complications of Mesh Repair Techniques: CT findings are emphasized . Rowell, A.; Rau, B.; Heldmann, M.; Sangster, G.; Richardson, K. Louisiana State University Health Sciences Center, Shreveport, LA Conclusion: This exhibit will aid the radiologist in forming a Address correspondence to M. Heldmann ([email protected]) basic differential diagnosis for infectious processes of the retro- peritoneum . Background Information: Abdominal wall hernias are a com- mon malady in the general surgeon’s practice, and nearly 100,000 ventral hernia repairs are performed annually in the E124. Identification and Clinical Significance of Twinkling United States . Traditional open hernia repair and newer laparo- Artifact (CME Credit Available) scopic methods are both associated with complications, and a Wang, D.; Kamaya, A. Stanford University, Stanford, CA range of mesh products are commercially available for onlay, Address correspondence to D. Wang ([email protected]) suture or tack fixation . The evolution of radiologic techniques from herniography, through ultrasound (US), to isotropic voxel CT Background Information: Twinkling artifact is a commonly seen has afforded imaging greater contribution in the detection of artifact in abdominal and pelvic imaging . This artifact is a rapidly clinically occult hernias, characterization of complex defects for alternating red, blue, green, yellow, and orange focus of aliasing preoperative planning, and detection of postoperative complica- seen posterior to a highly reflective or rough surface on color tions . The infinite multiplanar reformat (MPR) series and volume Doppler imaging . Accurate recognition of this artifact is important rendered (VR) techniques of MDCT are powerful tools with as this artifact is commonly seen in daily practice . which the general or subspecialist radiologist can become famil- iar with and display expected and unanticipated findings after Educational Goals/Teaching Points: The goals of the exhibit anterior abdominal wall herniorrhaphy . are to demonstrate the range of appearances and locations of twinkling artifact; to illustrate ways in which twinkling artifact can Educational Goals/Teaching Points: This educational exhibit be useful as a problem solving tool to lead to a correct diagnosis; will review the anatomy of the anterior abdominal wall with to provide methods to distinguish Twinkling artifact from true imaging and clinical correlation; illustrate the imaging appear- vascularity, and demonstrate pitfalls in which twinkling artifact ance of congenital and acquired abdominal wall hernias relate may be artifactually seen . basic surgical techniques of ventral hernia repair; depict the uncomplicated postoperative appearance of ventral hernia repair Key Anatomic/Physiologic Issues and Imaging Findings/ with mesh, and present the common perioperative and postop- Techniques: Twinkling artifact can be a very helpful tool in evalu- erative complications, with an emphasis on MDCT . ating many entities: renal stones (ureterovesicular junction [UVJ] stones which may otherwise be missed on grayscale imaging, Key Anatomic/Physiologic Issues and Imaging Findings/ staghorn calculi which may be difficult to delineate from adjacent Techniques: The exhibit will include operative images, MDCT echogenic fat, milk of calcium in calyceal diverticulum, simple and US of the normal abdominal wall; operative images, MDCT renal stones in which posterior acoustic shadowing is not clearly and US of ventral hernias, and MDCT with MPR and VR of post- demonstrable); gallbladder (adenomyomatosis, gallstones), and operative abscess, hematoma, seroma, extrusion and fistula for- bladder wall calcifications . Twinkling artifact associated with for- mation . eign bodies, and twinkling artifact seen in other areas such as calcified uterine fibroids, prostate, carotid artery plaque, etc . will Conclusion: Abdominal hernia and hernia repair procedures are be discussed . Techniques to distinguish twinkling from vasculari- ubiquitous, and as such are commonly encountered in the busy ty, such as recognition of twinkling artifact on spectral Doppler radiology practice . Familiarity with basic surgical techniques, tracings and understanding how changing pulse repetition fre- materials and expected postoperative findings promote the quency affects the appearance of twinkling artifact plus pitfalls detection of complications and allow imagers to communicate (confusing twinkling artifact with hypervascularity such as in the with and assist the surgeon performing abdominal herniorrhaphy . gallbladder or uterus, confusing twinkling artifact for an arterial-

218 El e c t r o n i c Ex h i b i t s : General, Emergency venous fistula in the kidney; confusing twinkling artifact with a and discuss the histopathologic correlation in order to have bet- hemodynamically significant stenosis in vascular imaging and set- ter understanding and correct usage of halo signs . ting machine parameters too low such that a truly vascular lesion is called twinkling artifact will be discussed . Educational Goals/Teaching Points: The various entities associ- ated with halo signs will be reviewed in terms of their key imaging Conclusion: Correct identification of twinkling artifact is impor- findings and histopathology . The goal of this pictorial review is to tant in Doppler ultrasound and allows for more precise diagnos- have a clear understanding of the various halo signs in wide spec- tic accuracy . trum of pathologic processes and different imaging modalities .

E125. CT Appearance of Juxtacaval Fat Mimicking as IVC Key Anatomic/Physiologic Issues and Imaging Findings/ Lipoma Techniques: This exhibit will review pathologic processes and Sidhu, R.; Bhatt, S.; Dogra, V. University of Rochester, Rochester, NY imaging findings of a variety of diagnostic entities that halo signs Address correspondence to R. Sidhu (ravinder_sidhu@urmc. are associated with, and illustrate and emphasize key imaging rochester.edu) findings that constitute halo signs in those diagnostic entities .

Background Information: Fatty mass in the intrahepatic portion Conclusion: A halo sign is described in a variety of pathologic of inferior vena cava (IVC) is unusual . This fat can be mistaken processes at multiple imaging modalities . In order to improve its for IVC lipoma on axial CT images . Multiplanar CT especially with diagnostic value, it is important to have a clear understanding of coronal images helps to demonstrate extraluminal nature of fat . the imaging findings and histopathology of the sign associated with a variety of diagnostic entities . Educational Goals/Teaching Points: Appearance of intralumi- nal fat within the intrahepatic portion of the IVC at or above the level of confluence of the hepatic veins is often misinterpreted as E127. Tumor Response Criteria: What Should a Radiologist IVC lipoma . This extraluminal fat actually represents a close asso- Know? (CME Credit Available) ciation of pericaval, extraluminal adipose tissue with the medi- Braschi , M.1; Ramaiya, N.2; Zondervan, R.1; Urban ,T.1; Van Den al aspect of the immediately subdiaphragmatic IVC . Multiplanar Abbeele, A.2; Harris, G.1 1. Massachusetts General Hospital, CT reconstruction is helpful in demonstrating the extraluminal Boston, MA; 2. Dana Farber Hospital, Boston, MA nature of juxtacaval fat collections, thereby avoiding misinterpreta- Address correspondence to M. Braschi ([email protected]) tion and further unnecessary follow-up examinations . Background Information: When imaging is used to monitor the Key Anatomic/Physiologic Issues and Imaging Findings/ efficacy of cancer treatment, radiologists are facing an increasing Techniques: The axial and reconstruction CT images of fat in the demand from oncologists to use imaging assessment criteria juxtacaval region will be shown . The key features as how to dif- such as RECIST (Response Evaluation Criteria for Solid Tumors), ferentiate normal juxtacaval fat from IVC lipoma, and fat throm- WHO (World Health Organization), and Cheson . In order to pro- bus will be discussed . vide objective and consistent scan reviews, radiologists should become familiar with the guidelines utilized by these standard Conclusion: Juxtacaval fat mimics lipoma in the IVC . Special con- imaging assessment criteria . The goal of this exhibit is to familiar- sideration will be made so as to be familiar with their normal ize viewers with these important measurement guidelines using appearances of fat in this location which is an anatomical variant . test cases and quizzes . It is important to identify this particular entity which is much less talked about so as to avoid further unnecessary investigations . Educational Goals/Teaching Points: Longitudinal imaging assessment in the evaluation of patients with cancer and in clini- cal trials plays an integral role in patient treatment decisions . The E126. Halos in the Bellows, Hallows and Others (CME Credit above-mentioned criteria incorporate both quantitative and quali- Available) tative methods to assess tumor response to therapy . However, in Hwang, S.; Ginsberg, M.; Gollub, M. Memorial Sloan-Kettering order to obtain the most accurate study results, the readers Cancer Center, New York, NY require training, experience and knowledge on measurement cri- Address correspondence to S. Hwang ([email protected]) teria guidelines .

Background Information: A halo sign has been described in a Key Anatomic/Physiologic Issues and Imaging Findings/ variety of pathologic processes of multiple organ systems . In the Techniques: In this exhibit, we will provide a synopsis of each lung, the sign was initially introduced to describe hemorrhagic criteria and corresponding test cases and quizzes to demonstrate nodules of invasive pulmonary aspergillosis at CT . Now the sign is a variety of teaching points such as lesion selection (“target” vs . also linked to multiple infectious pathogens, pulmonary neo- “nontarget”), methods of measurement (CT and MRI), consisten- plasm and noninfectious inflammatory processes . In the liver, a cy across imaging time points, and response evaluation: stable periportal halo sign at CT and MRI is associated with neoplastic disease (SD), partial response (PR), progression disease (PD), and non-neoplastic processes which expand periportal spaces . A complete response (CR), complete response unconfirmed (Cru), halo sign in the liver and spleen at ultrasound is often indicative relapse disease (RD), unknown . of neoplasm . Within the gastrointestinal tract, the sign is associat- ed with infectious and inflammatory processes affecting intestinal Conclusion: At the conclusion of this presentation, the viewers mural layers . In the bones, the halo sign at MRI is highly specific will gain confidence and knowledge about three of the most for osteoblastic metastases . The goal of this review is to illustrate common measurement criteria utilized in radiology to assess imaging findings of halo signs of various pathologic processes response to therapy .

219 El e c t r o n i c Ex h i b i t s : General, Emergency

E128. Sternoclavicular Joint Dislocations: Imaging Findings venous sinuses . Traumatic dural venous sinus thrombosis may With Intraoperative Correlation (CME Credit Available) mislead an inexperienced radiologist to interpret the findings as Chakarun, C.; Tumyan, L.; Demetriades, D.; Wolfson, N.; White, E. simply hemorrhage from the traumatic injury . Yet the failure to University of Southern California, Los Angeles, CA recognize the difference has significant implication in patient Address correspondence to C. Chakarun ([email protected]) management . Many other abnormalities, such as blunt vascular injury or chronic injuries from child abuse, also can potentially be Background Information: Our purpose is to describe the plain associated with dire consequences . These injuries can be isolat- radiographic and CT imaging findings in patients with sternocla- ed, subtle and confusing, making them easy to be misinterpreted . vicular joint dislocations at our Level I trauma center, and corre- The purpose of this educational exhibit is to increase the aware- late these findings with intraoperative reports and photographs . ness of these entities in the general radiology community, so that improved patient care can be attained . Educational Goals/Teaching Points: Sternoclavicular joint dis- locations usually cannot be diagnosed on plain radiographs, and Educational Goals/Teaching Points: The goals are to review contrast-enhanced CT is often necessary . Anterior dislocations are under-recognized traumatic injuries and their potentially serious nine times more common than posterior dislocations, however, complications in the head and neck; to review the criteria and posterior dislocations can be life-threatening due to compromise algorithms for radiological workup in traumatic injuries of the of the trachea, esophagus, and great vessels . Herein, we provide head and neck, with an emphasis on the value of advanced stud- examples of both anterior and posterior sternoclavicular joint dis- ies such as MRI, MR angiography (MRA), CT angiography (CTA) locations from our Level I trauma center, demonstrating plain and susceptibility weighted imaging, and to review the patient radiographic and CT imaging findings . These findings are correlat- management issues related to diagnosis of uncommon injuries in ed with emergency department photographs, intraoperative pho- the head and neck and their complications, as pertinent for a tographs, and intraoperative reports . Our goal is for the reader to radiologist . understand the serious sequelae that can result from sternocla- vicular joint dislocation, and to have a better understanding of Key Anatomic/Physiologic Issues and Imaging Findings/ the anatomy and associated imaging findings . Techniques: Cases related to traumatic injuries of the head and neck from our institutions are reviewed systematically . Imaging Key Anatomic/Physiologic Issues and Imaging Findings/ features of uncommon injuries, injuries with subtle findings or Techniques: Both anterior and posterior sternoclavicular joint unexpected complications are reviewed . Measures to avoid diag- dislocations indicate high-energy trauma . Anterior dislocations nostic pitfalls, guidelines for diagnostic workup in particular the result from direct trauma that causes separation of the anterior use of advanced imaging techniques such as CT , CTA, sternoclavicular ligament . Posterior sternoclavicular joint disloca- MR venography, MRA and susceptibility weighted imaging are tions are caused by posterolateral compressive forces in the discussed . A brief discussion on the impact of the radiological shoulder that dislocate the medial aspect of the clavicle posterior diagnosis on patient management is also included . to the sternum . Cases have also been reported in which posterior dislocation results from direct blunt trauma at the medial clavicu- Conclusion: Although imaging evaluation of traumatic injuries of lar head . Contrast-enhanced CT is the imaging modality of choice, the head and neck are often considered straightforward, uncom- since the great vessels need to be evaluated and plain radiogra- mon injuries or injuries with subtle findings are not as well rec- phy may not adequately assess joint alignment . Closed reduction ognized . These injuries can be associated with severe complica- is the preferred treatment, but patients presenting more than 48 tions . Prompt recognition of these injuries and their potential hours after injury often require surgical intervention . complications can affect patient management substantially .

Conclusion: Sternoclavicular joint dislocation can be life-threat- ening, and understanding the anatomy and imaging findings of E130. Blast and Ballistic Trajectory Analysis with MDCT: the associated injured structures is crucial to prompt diagnosis Applications of Volume Acquisition and Complex Planar and treatment . Through intraoperative photographs and images Reformats in Trauma Diagnosis (CME Credit Available) from our Level I trauma center, the radiologist will become more Folio, L.; Backus, C. Uniformed Services University of the Health familiar with this important diagnosis . Sciences, Bethesda, MD Address correspondence to L. Folio ([email protected])

E129. Traumatic Injury of the Head and Neck: Imaging of the Objective: The authors describe and quantify complex anatomic “Not-So-Obvious” that Can Make a Big Difference (CME planes that are now possible with volumetric MDCT imaging . We Credit Available) propose more objective nomenclature labeled para-axial, para- Zeinati, C.1; Poon, C.1,2; Chang, J.1; Kubal, W.2 1. SUNY Upstate coronal and parasagittal image reconstructions . A brief overview Medical University, Syracuse, NY; 2. Yale University School of of trajectory analysis using volumetric imaging and resultant mul- Medicine, New Haven, CT tiplanar reconstruction will also be introduced . The authors also Address correspondence to C. Poon ([email protected]) introduce a quantifiable methodology for more accurately describing these complex planes for consistency of reporting Background Information: Imaging of traumatic injury of the penetrating trauma and showing how the radiologist can be head and neck is often considered a straightforward task in radi- helpful in incident analysis . ological practice . Nevertheless, there are many subtle findings in traumatic imaging that are often overlooked, but failure to recog- Materials and Methods: Several penetrating trauma CT studies nize them may affect patient management significantly . An exam- from a deployed military hospital in Iraq were reviewed and ple is venous sinus thrombosis associated with injury of the dural selected to apply this more objective planar description . A few of

220 El e c t r o n i c Ex h i b i t s : General, Emergency the cases reviewed are presented demonstrating application of Key Anatomic/Physiologic Issues and Imaging Findings/ the complex anatomic planes described . Detailed anatomic art- Techniques: The spectrum of thoracic blastomycosis will be work tailored to the cases highlight application of more clearly discussed and illustrated by radiography, CT, MR, and PET . The defined planes . Lastly, a methodical trajectory analysis system incidence and presentation of extrapulmonary blastomyosis and numerically descriptive plane combination using an anatom- will be discussed . Prostate and genitourinary lesions will be illus- ic reference point is proposed . trated by CT and MR imaging . Meningeal and brain lesions will be discussed and illustrated by MR and CT imaging . Bone and joint Results: The cases reviewed consistently identify and more effec- lesions will be shown by radiography and MR imaging . Abdominal tively communicate the complex intersecting planes along the and pelvis involvement will be illustrated by CT imaging . trajectory of various missile fragments . Finding a trajectory of one fragment often increases conspicuity of other fragments that may Conclusion: North American blastomycosis is common in the have otherwise gone undetected . Parallel para-axial interpreta- central and southeast US . Most patients present with tion based on reference fragments helps find other missiles . chest abnormalities but extrapulmonary lesions are common . Quantification of intersecting planar angles and magnitude from Chest lesions have a wide variety of appearances . The most com- a reference point allows localization of remaining fragments . This mon extrapulmonary lesions are to skin, bone, prostate, and is especially helpful in blast injuries that have multiple fragments . meninges . Knowledge of the spectrum of chest and extrapulmo- nary lesions will put the radiologist in a position to suggest the Conclusion: The authors demonstrate application of a novel tra- diagnosis . Early diagnosis and treatment improve the prognosis, jectory analysis by more objectively defining complex planes with especially in immune compromised patients . a proposed lexicon and anatomic modeling . The authors further quantify locations by a proposed anatomical polar coordinate system based on a single reference point . The authors believe E133. Incidentalomas: A Case-Based Review (CME Credit this may be useful in consistent recording and communicating Available) the location of multiple blast and ballistic fragments . Determining Nehme, T. Radia, E Wenatchee, WA and describing trajectory angles using standard polar coordinates Address correspondence to T. Nehme ([email protected]) may help the study of individual incidents as well as for an epi- demiologic baseline in recording and comparing gunshot and Background Information: With the ever increasing accuracy of blast trajectories for years to come . Since image data is occasion- cross-sectional imaging, more incidental findings are being recog- ally not available during evacuation up the echelons, more accu- nized that are unrelated to the problem being evaluated . This has rate recording of trajectories and quantified planes is paramount . created a dilemma for both the radiologist and referring physi- cian in evaluating these abnormalities . The purpose of this exhibit is to familiarize the audience with the different incidentalomas E131. North American Blastomycosis visualized on cross-sectional imaging and to provide an algorithm Demos, T.; Brylka, D.; Posniak, H. Loyola University Medical for their work up based on the current literature . Center, Maywood, IL Address correspondence to T. Demos ([email protected]) Educational Goals/Teaching Points: The goals are to familiar- ize the audience with the different incidentalomas detected on Background Information: North American blastomycosis is a cross-sectional imaging and to present algorithms in the work up fungal disease that involves multiple organ systems . Initial infec- of incidentalomas based on current literature . tion is due to inhalation of B . dermatitidis from soil, vegetation or rotting wood . In North America, the disease is most common in Key Anatomic/Physiologic Issues and Imaging Findings/ the central and southeast US and southern Canada . Most Techniques: Incidentalomas in neuroradiology on cross-sectional patients present with acute to chronic pulmonary symptoms and imaging, incidentalomas in the chest on cross-sectional imaging, 85% have chest imaging findings that can have the appearance and incidentalomas in the abdomen and pelvis on cross- section- of pneumonia, tuberculosis, or malignancy . Hematogenous al imaging will be discussed . spread to other organs may not be evident for weeks to years . Organ involvement includes skin (30%), bones and joints (20%), Conclusion: Incidentalomas on cross-sectional imaging are fre- prostate and genitourinary organs (10%), and meninges and quently encountered by radiologists . The work up of such find- brain (3%), but all organs have been affected . Variable finding on ings however remains a dilemma . The exhibit presented will chest imaging can make diagnosis difficult . When patients hopefully help the interpreting radiologist in the work up of these present with extrapulmonary disease, diagnosis can be even findings with algorithms based on current literature . more difficult . The informed radiologist can be instrumental in contributing to the early diagnosis in these patients . Early diagno- sis can avoid lengthy evaluations and invasive procedures, and E134. Ciliary Disease: From the Ultrastructure Level to the early treatment can be crucial to survival in immune compro- Imaging Manifestations mised patients . Escalante, B.1; Restrepo, C.1; Prasad , S.1; Varon, C.2; Varon, H.2; Murcia, S.2 1. University of Texas Health Sciences Center at San Educational Goals/Teaching Points: The exhibit will illustrate Antonio, San Antonio, TX; 2. Universidad Nacional de Colombia, the spectrum of findings of blastomycosis in the chest as shown Bogota, Colombia by various imaging modalities . Extrathoracic involvement will be Address correspondence to B. Escalante ([email protected]) discussed and lesions of the bones and joints, prostate and geni- tourinary organ, meninges, brain, and abdomen and pelvis will Background Information: The dysfunction of one type of cilium, be illustrated . The association of lesions in a patient suggesting called motile cilia, leading to manifestations of primary ciliary dysk- the diagnosis will be discussed . inesia and Karatagener’s syndrome is well studied . Recent studies 221 El e c t r o n i c Ex h i b i t s : General, Emergency suggest the role of another type of cilium, called primary cilium, in lymph node groups, evaluation of lymphomas with typical and development of polycystic kidney disease and laterality defects . atypical presentations and assessment of other diagnoses in the The purpose of this exhibit is to discuss the two types of cilia and differential for the demonstrated imaging findings will be reviewed . illustrate the imaging characteristics of their associated diseases . Key Anatomic/Physiologic Issues and Imaging Findings/ Educational Goals/Teaching Points: The exhibit will discuss Techniques: A strong background in normal anatomy is required the difference between the two types of cilia: motile and primary; in order to identify pathologic lymphoid tissue . While evaluation review and help the learner understand the pathophysiology of of scans typically incorporates size criteria of nodes, it is impor- motile cilia dysfunction in the mucosa of the respiratory airways tant to use PET in conjunction for identification of metabolically leading to primary ciliary dyskinesia and Karatagener’s syndrome; active nodes . Imaging modalities including plain film radiogra- discuss the emerging evidence of the role of another type of cilia, phy, cross-sectional imaging (CT and MRI) as well as PET will be the primary cilia, in development of polycystic kidney disease and depicted for specific cases from the standpoint of both diagnosis laterality defects such as situs inverus and heterotaxias, and illus- and follow-up . Cases exemplifying typical presentations of lym- trate imaging characteristics of diseases associated with dysfunc- phoma in the mediastinum and in the spleen will be shown . tion of the two types of cilia . Development of lymphoma in extranodal sites such as in the adrenal gland, in breast tissue, kidney, brain, and in lung paren- Key Anatomic/Physiologic Issues and Imaging Findings/ chyma will be illustrated . Techniques: Cilia are organelles that are present in most human cells and are classified based on their microtubular configura- Conclusion: There have been tremendous strides in the treat- tions . The motile type has a 9+2 microtubule configuration . Well ment of NHL with many patients achieving remission and/or known are the abnormalities within motile cilia causing cellular cure . However, it is not only the improved understanding of the dysfunction leading to respiratory disease and infertility . The pri- pathophysiology and treatments that are responsible for these mary type has a 9+0 microtubule configuration and was tradi- outcomes; but also, the improved imaging techniques for diagno- tionally thought of as a vestigial cellular structure . However, sis . Lymphoma is often described at the reading board as “the recent discoveries have suggested that the absence or dysfunc- great masquerader ”. Knowledge of its typical and atypical pres- tion of embryonic primary cilia may affect human development . entations will provide the radiologist with tools to carefully These discoveries extend the list and imaging characteristics of review scans and offer the possible diagnostic considerations so ciliary diseases to include those that involve abnormal organ that a diagnosis is not missed . form and location such as polycystic kidney disease, situs inver- sus, and heterotaxias . The imaging characteristics of the associat- ed diseases of these two types of cilia will be presented . E137. Emergency Radiographs: What all First Year Residents Should Know (CME Credit Available) Conclusion: Well known are the abnormalities of motile ciliary Lee, B.; Whitehead, M.; Scheel, J.; Dowell, J.; Lambert, D. function leading to tissue and cellular dysfunction as in primary cili- University of Virginia, Charlottesville, VA ary dyskinesia and Karatagener’s syndrome . Recent studies have Address correspondence to B. Lee ([email protected]) linked another type of cilium, the primary cilium, in diseases such as polycystic kidney disease, situs inverus, and heterotaxias . With these Background Information: Certain findings on radiographs war- new discoveries, imaging characteristics of ciliary disease encom- rant a timely intervention . Often, these images are initially pass, not only those that are the consequences of abnormal organ encountered by a less experienced radiology resident . Prompt function, but also those of abnormal organ form and location . recognition of these findings are essential to patient care .

Educational Goals/Teaching Points: The goal is to present vari- E135. Non-Hodgkin’s Lymphoma: The Great Masquerader ous radiographic findings of “do not miss on call” lesions . (These (CME Credit Available) will be presented in case-quiz format .) Warsofsky, I.; Enochs, W. Bryn Mawr Hospital, Bryn Mawr, PA Address correspondence to I. Warsofsky ([email protected]) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The following cases will be presented in quiz format Background Information: Lymphoma is a broad classification of with images and answers with explanation (with treatment in neoplastic processes which includes Hodgkin’s lymphoma, non- selected cases) . 1 . Chest—pneumothorax, tension; pneumothorax Hodgkin’s lymphoma (NHL), and other related disorders . on supine radiograph (deep sulcus sign); pneumomediastinum; Lymphomas are solid malignancies which typically occur in pneumopericardium, and lobar collapse secondary to bronchial lymph nodes and primary lymphoid tissue . However, atypical occlusion; 2 . Musculoskeletal—compound (open) fracture; knee, appearances have found in other organs, particularly for NHL, segond fracture; foot, Lis Franc fracture-dislocation; hand, game and it is important to be knowledgeable of both its common and keeper’s thumb; hand, Bennet’s fracture; elbow, epicondylar frac- uncommon appearance . Such knowledge may expedite a ture; spine, flexion tear drop; spine, posterior spinal ligamentous patient’s diagnostic workup as often the symptoms and/or physi- injury; skull/spine, craniocervical dissociation, and spine, anklyos- cal examination are not sufficiently revealing . ing spondylitis with fracture; 3 . Abdomen—pneumoperitoneum; retroperitoneal air; necrotizing enterocolitis; pneumobilia; pneu- Educational Goals/Teaching Points: Familiarity with the evalua- motosis intestinalis; portal venous gas; emphysematous cholecys- tion of NHL is necessary to ensure that staging is done correctly as titis; emphysematous cystitis, and small bowel obstruction this has a direct impact on the treatment . Case examples of both typical and atypical presentations of lymphoma will be illustrated . Conclusion: Described above are some of the plain radiographic The educational goals of this project include: review of the normal findings which require prompt attention and treatment .

222 El e c t r o n i c Ex h i b i t s : Gastrointestinal

Key Anatomic/Physiologic Issues and Imaging Findings/ GI/Li v e r /Bi l i a r y /Pa n c r e a s Techniques: Atypical appearances of appendicitis including tip appendicitis, air-filled appendicitis, nondilated appendicitis, and E138. Postgadolinium MR Imaging With Multiplanar appendicitis masquerading as nonsurgical bowel disease will be Reconstruction of Fistula In Ano presented with CT . Potential CT mimickers of appendicitis includ- Dalal, T.; Paspulati, R. Case Western Reserve University, Solon, OH ing Meckel’s diverticulum, appendiceal mucocele, appendiceal Address correspondence to R. Paspulati (prajmohan@hotmail. carcinoma, and secondary appendiceal inflammation will also be com) presented .

Objective: The goals are for the learner to understand the anat- Conclusion: Although CT has high negative and positive predic- omy, pathogenesis and types of fistula in ano; understand the tive value in the evaluation of acute appendicitis, atypical appear- technique of MR imaging of fistula in ano, and understand the ances and potential mimickers of appendicitis on CT can be con- role of MR imaging in treatment of fistula in ano . fusing . Knowledge of these entities can aid in clarifying the diag- nosis . Materials and Methods: This is a review of MR imaging of the pelvis for diagnosis and lay out of peri anal fistulae . From 2005 to 2008, 56 cases of suspected fistula in ano had MR imaging . E140. Pitfalls in CT Diagnosis of Appendicitis (CME Credit Ten of them had known inflammatory bowel disease and five of Available) them had hematological malignancy under treatment with neu- Tappouni, R.; Sarwani, N.; Chamarthi, S.; Peterson, C. Penn State, tropenia and perianal abscess . The remaining large number of Hershey, PA cases are without a predisposing cause . MR protocol included Address correspondence to R. Tappouni ([email protected]) high resolution T2 fast spin echo (FSE) in three orthogonal planes, Axial T2 FSE with fat suppression and 1 .5 mm thin post- Background Information: Acute appendicitis is a common gadolinium T1-weighted images . Multiplanar reconstructions are cause of acute abdominal pain requiring emergent abdominal obtained in all patients to demonstrate the fistulous tract . surgery . CT of the abdomen and pelvis is increasingly used in making the diagnosis and therefore avoiding delay in manage- Results: MR imaging findings are correlated with operative find- ment . While the overall accuracy of CT is high, numerous pitfalls ings . The entire length of the fistula is well documented in exist which may deceive radiologists, resulting in a false negative T2-weighted images and confirmed with postgadolinium images or false positive diagnosis . These pitfalls include atypical locations in all patients . The wall of the fistula is well demonstrated on of the appendix, inflammation of the appendiceal tip or postap- postgadolinium images due to dense enhancement of inflamma- pendectomy stump, presence of coexisting lower abdominal tory tissue . The fistulas are classified into intersphincteric and pathology and technical factors . trans-sphincteric types . Associated branching side tracks and abscess are well demonstrated, which helped the surgeon in sur- Educational Goals/Teaching Points: The goals are to demon- gical management . strate radiologic pitfalls in CT diagnosis of appendicitis; review the differential diagnosis of appendicitis and right lower quadrant Conclusion: MR imaging with high resolution T2-weighted imag- pain; review the significance of various CT findings in the diagno- es and postgadolinium images provide an anatomical lay out of sis of appendicitis, and illustrate the pitfalls in the diagnosis of the peri anal fistula for surgical management . The complex fistu- appendicitis . lous tracts are very well displayed in the multiplanar reconstruct- ed postgadolinium images . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: An auto-tutorial will consist of cases divided into four categories: 1 .Variants: tip appendicitis, abnormal location, E139. Test Your Appendicitis IQ: Atypical Appearances and and stump appendicitis; 2 Technical. Pitfalls: effect of oral and IV Potential Mimickers on CT (CME Credit Available) contrast use in establishing the diagnosis of appendicitis; 3 . Mooney, S.; Rubens, D.; Fultz, P.; Jones, L. University of Rochester, Conditions Leading to Misdiagnosis of Appendicitis: false nega- Rochester, NY tives: ovarian pathology, small bowel obstruction, terminal ileitis; Address correspondence to S. Mooney (scott_mooney@urmc. coexisting inflammatory and neoplastic processes: appendicitis rochester.edu) coexisting with diverticulitis, and appendiceal carcinoma, and 4 . Conditions Leading to False Positive Diagnosis of Appendicitis: Background Information: Acute appendicitis is the most com- wall thickening of appendix in an amyand hernia, Crohn’s dis- mon indication for emergent surgery . CT is the primary imaging ease, and appendiceal carcinoid . modality used for evaluating abdominal pain in suspected appendicitis, with ultrasound and MRI usually reserved for chil- Conclusion: In order to achieve a high degree of accuracy in the dren and pregnant women . The classic appearance of appendici- CT diagnosis of appendicitis, careful attention to technique and tis has been described on CT, however, atypical appearances of interpretation are required . The radiologist should be aware of appendicitis and its mimickers can create difficulty in interpreta- the features leading to false positive and negative diagnosis, in tion . These confounding diagnostic challenges will be presented . addition to anatomic variants .

Educational Goals/Teaching Points: The goals are to review the normal appearance of the appendix, and present typical and atypical appearances of appendicitis, and potential mimickers .

223 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E141. The Vermiform Appendix: The Worm That Turned appearances of occult/missed appendicitis during on-call at a (CME Credit Available) single institution over the last six years . Goud, N.1; Jati, A.1; Goud, A.1; Ramaiya, N.2 1. VA Boston Health Care System, West Roxbury, MA; 2. Dana Farber Cancer Institute, Educational Goals/Teaching Points: The goals are to provide a Boston, MA pictorial review of various presentations of missed acute appen- Address correspondence to A. Jati ([email protected]) dicitis, and to review the complications and outcomes of missed acute appendicitis . Background Information: The objective is to describe and illus- trate multimodality imaging findings of appendiceal pathology Key Anatomic/Physiologic Issues and Imaging Findings/ and to identify differentiating imaging features in both neoplastic Techniques: The exhibit will include MDCT and ultrasound (US) and non-neoplastic conditions of the appendix . presentations of missed acute appendicitis; radiological-patholog- ical correlation of acute appendicitis; background information on Educational Goals/Teaching Points: This exhibit will provide a acute appendicitis ; meta-analysis of literature on delayed diag- concise and comprehensive review of appendiceal pathology, nosis of acute appendicitis and its outcomes, and outcome and and case examples with specific features that help to differenti- complication analysis of patients with missed acute appendicitis . ate these disease processes . Persons who view the exhibit will learn to identify the imaging findings of these conditions . Conclusion: Diagnosis of acute appendicitis with MDCT or US can be challenging . Missed acute appendicitis increases patient Key Anatomic/Physiologic Issues and Imaging Findings/ healthcare cost, morbidity and mortality . Radiologists need to be Techniques: Acute appendicitis is the most common pathology aware of the variety of presentations of acute appendicitis for involving the appendix . This may present with a myriad of typical optimal patient care and prognosis . or atypical imaging findings . Primary tumors of the appendix are rare and most tumors are incidentally detected on routine imag- ing . It is important to recognize the underlying tumor to allow for E143. MDCT in Imaging of Epiploic Appendagitis: A Pictorial optimal treatment . Benign tumors involving appendix include Essay (CME Credit Available) lipoma, leiomyoma, adenoma, and neuroma . Malignant tumors Gupta, S.; Tatineny, K.; Sadler, M.; Yeghiayan, P. St Vincent’s include carcinoid tumor, adenocarcinoma, lymphoma and gas- Catholic Medical Center, NY, New York, NY trointestinal stromal tumor (GIST) . Appendiceal luminal obstruc- Address correspondence to S. Gupta ([email protected]) tion is a common manifestation of most appendiceal disease entities including appendicitis, mucocele and appendiceal Background Information: The goals of the exhibit are to illus- tumors . Mucocele implies abnormal accumulation of mucus and trate the radiological findings of epiploic appendagitis as seen on is caused by appendiceal obstruction . It can be seen in non-neo- MDCT; discuss the main differential diagnoses of epiploic plastic and neoplastic conditions . Pseudomyxoma peritonei appendagitis, and to discuss the impact of imaging findings on results from the perforation of mucocele and it is important to management . differentiate it from complicated ascitis and peritoneal carcino- matosis . Appendiceal tumors may have a greater soft tissue com- Educational Goals/Teaching Points: Teaching points include ponent in the pericecal area compared to appendicitis . Nodes normal anatomy, signs and symptoms, epiploic appendagitis may be larger but not necessarily more numerous . Appendiceal (MDCT findings including hyperattenuating rim sign), and discus- lymphoma usually have even more marked soft tissue thickening sion on the importance of accurately diagnosing this condition with maintained vermiform morphology of appendix . Carcinoid and its impact on management . tumor is seen in distal appendix in young patients, because of the small size the primary tumor may be difficult to image . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The exhibit will distinguish the following differential Conclusion: On completing this exhibit the reader should be diagnoses from epiploic appendagitis: acute diverticulitis, omen- able to list the common and uncommon pathology that affects tal infarction, acute appendicitis, panniculitis, and a fat-containing the appendix and understand the role of imaging in making the tumor (liposarcoma) . diagnosis of appendiceal pathology . The reader should also be aware of the specific imaging findings that differentiate these var- Conclusion: In an era of increased imaging for acute abdominal ious pathologic entities . pain, radiologists are more likely to encounter the entity of epip- loic appendagitis . Identifying its characteristic imaging features is important, because it may avoid unnecessary antibiotic therapy E142. Oh No! Did I Miss That? On-Call Acute Appendicitis and possible surgery, as this entity is conservatively managed . (CME Credit Available) Lee, J.; Chen, C.; Suh, R.; Kadell, B.; Lee, E. University of California-Los Angeles Medical Center, Los Angeles, CA E144. Endoscopic Retrograde Cholangiopancreaticogram: A Address correspondence to E. Lee ([email protected]) Review of Normal Anatomy and Common Pathologies (CME Credit Available) Background Information: Acute appendicitis has extremely var- Lee, B.; Whitehead, M.; Durst, C.; Shaffer, H.; Lambert, D. ied clinical presentations . A delayed or missed diagnosis of acute University of Virginia, Charlottesville, VA appendicitis may result in severely detrimental consequences . Address correspondence to B. Lee ([email protected]) Acute appendicitis cases seen during on-call can be especially difficult and challenging . This comprehensive pictorial review will Background Information: Endoscopic retrograde cholangiopan- demonstrate the spectrum of radiological findings and CT creatography (ERCP) is a technique that combines endoscopy

224 El e c t r o n i c Ex h i b i t s : Gastrointestinal and fluoroscopy to identify and treat diseases within the biliary Conclusion: This interactive exhibit will enable users to familiar- and pancreatic ductal systems . It is the test of choice in patients ize themselves with the endoscopic instruments that are used in with obstructive jaundice . Though most radiologists no longer ERCP cases and the reasons why they are used . This will allow perform these procedures directly, fluoroscopic images are often the radiologist to provide a more accurate and meaningful report . submitted for review . Knowledge of normal anatomy and recog- nition of abnormalities vs . abnormality is essential . E146. Ultrasound Analysis of the Biliary System in Normal Educational Goals/Teaching Points: The goals are to review and Diseased States normal anatomy (diagram, picture, and fluoroscopic images are Matcuk, G.1; Vaseghi, M.2; Ralls, P.1 1. University of Southern included) of the biliary and pancreatic ductal system; identify California, West Los Angeles, CA; 2. University of California, Los common pathology within the biliary and pancreatic ductal sys- Angeles, Los Angeles, CA tem, and recognize artifacts which may mimic disease . Address correspondence to G. Matcuk ([email protected])

Key Anatomic/Physiologic Issues and Imaging Findings/ Objective: The objective is to determine the normal size and Techniques: Fluoroscopic images from ERCP will be presented . range of the intrahepatic and extrahepatic (common) bile ducts In selected case additional imaging modalities are presented and gallbladder, adjusted for demographic data, and to assess (, MR cholangiopancreatography [MRCP], the effects of a variety of pathologic states on these values . CT, cholangiogram) . The exhibit will focus on the biliary ductal system (cholelithiasis and choledocolithiasis, pseudolithiasis [air Materials and Methods: Data from 4,119 abdominal ultra- bubbles, etc ],. cholangiocarcinoma, primary sclerosing cholangitis, sounds were retrospectively analyzed . Normal patients were con- bile leak, postoperative T-tube cholangiogram, and biliary stric- sidered to be those without sonographic evidence of liver, gall- ture, benign and malignant) and the pancreatic ductal system bladder, biliary, or pancreatic disease . The values for the extrahe- (pancreatic ductal stone; pancreatic ductal stricture, benign patic bile duct (EHD), left (LIHD) and right (RIHD) intrahepatic [chronic pancreatitis] and malignant, intraductal papillary muci- ducts, gallbladder wall thickness, and gallbladder volume in nor- nous neoplasms [IPMN] and pancreas divisum) . mal patients were evaluated with respect to age, gender, ethnici- ty, and cholecystectomy status . These values were compared Conclusion: ERCP is the test of choice in patients with obstruc- using multivariate analysis to those in a variety of diseased states, tive jaundice . Though most radiologists no longer perform these including cirrhosis, fatty liver, gallstones, sludge, cholecystitis, and procedures directly, identification of normal biliary and pancreatic biliary obstruction . ductal anatomy and recognition of common pathology on fluoro- scopic images are essential . Results: A total of 1,484 of the 4,119 abdominal were classified as normal . The frequency of cirrhosis was 9 .6%, fatty liver 30 0%,. gallstones 23 .9%, sludge 8 .5%, cholecystitis E145. Radiographic Appearance of Endoscopic Retrograde 1 .0%, and biliary obstruction 2 .0% . The EHD, RIHD, LIHD, and Cholangiopancreatography Instruments with Pictorial and gallbladder wall thickness and volume in normal patients were Functional Correlation 3 .8 ± 1 .6 mm, 1 . 9± 1 .9 mm, 1 .9 ± 1 .1 mm, 2 6. ± 1 .6 mm, and Kaplan, K.; Hartman, D. Penn State Milton S. Hershey Medical 242 ± 234 mL, respectively . Increasing EHD values correlated Center, Harrisburg, PA with increasing RIHD, LIHD, and gallbladder volume measure- Address correspondence to K. Kaplan ([email protected]) ments (p<0 0001). . There were small but statistically significant differences in normal EHD diameter with age (increase of 0 .02 ± Background Information: Endoscopic retrograde cholangiopan- 0 .11 mm/year, p<0 001),. gender (0 .3 ± 1 6. mm greater in creatography (ERCP) is invaluable in the evaluation of disorders females than males, p<0 .0001), and cholecystectomy status (1 .0 of the pancreaticobiliary system . The interpretation of these imag- ± 1 .6 mm greater in cholecystectomy patients, p<0 .0001) . es can be challenging as there is often uncertainty pertaining to Patients with fatty liver had smaller mean EHD measurements the type and purpose of the various endoscopic instruments (difference of 0 .4 ± 1 .6 mm, p=0 0003). compared to normals . being used . The gallbladder wall was thicker in patients with gallstones, sludge, and cholecystitis by 0 4. ± 1 .4 mm (p=0 0049),. 0 5. ± 1 .4 Educational Goals/Teaching Points: The exhibit is an auto-tu- mm (p=0 .0019), and 3 .1 ± 1 .6 mm (p<0 0001),. respectively, torial . A series of slides will review the various instruments within after adjusting for interdependence, age, and gender . In the pres- a typical ERCP endoscope . Gross photographs of the individual ence of biliary obstruction, the mean values for EHD, RIHD, LIHD, components will be presented along with corresponding radio- and gallbladder volume were significantly higher compared to graphic images . Details regarding the function of the individual normal subjects by 6 .0 ± 2 .1 mm, 4 2. ± 1 .4 mm, 4 1. ± 1 .4 mm, instruments will be provided while radiographs from actual ERCP and 171 ± 207 mL, respectively (p<0 0001. for all values) . cases will be used to correlate the structure and function . Examples of the instruments that will be discussed include guide Conclusion: Ultrasound is an excellent tool for the evaluation of wire, biliary extraction balloon, triple lumen needle knife, papil- the biliary system . This study clarifies normal values and ranges latome/sphincterotome, stone basket, pancreatic sized dilation for bile duct and gallbladder measurements, adjusted for demo- balloon, biopsy forceps and wire cytology brush . graphic data, and evaluates these measurements in a variety of common pathologic states . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Bile ducts, pancreatic ducts, biliary diseases, and pancreatic diseases will be discussed .

225 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E147. Biliary Ductal Plate Malformations: From the Conclusion: This exhibit will be a comprehensive review of the Embryology to the Imagiology imaging features of intrahepatic and extrahepatic cholangiocarci- Castro, M.; Almeida, A.; Silva, N.; Melao, L.; Pereira, J. Hospital de noma on MDCT and dynamic contrast-enhanced MRI . Pathologic São João, Porto, Portugal correlates for the characteristic imaging findings will be discussed Address correspondence to M. Castro ([email protected]) and illustrated . Features that determine resectability and impact surgical planning will be reviewed . Background Information: The ductal plate is a cylindric layer of cells that surrounds the branches of the portal veins that will form the biliary ducts after remodeling and partial involution . Ductal E149. Primary Sclerosing Cholangitis: Imaging Features plate malformation disorders can result in biliary atresia and in Shaikh, A.1; Hammond, N.2; Berggruen, S.2; Harmath, C.2; fibropolicystic liver diseases, when the ductal plates are insuffi- Nikolaidis, P.2 1. Chicago Medical School, North Chicago, IL; 2. ciently reabsorbed . The timing or stage of development arrest Northwestern University Feinberg, Chicago, IL determines the resulting clinicopathologic disorder such as con- Address correspondence to S. Berggruen (senta.berggruen@nmff. genital hepatic fibrosis, biliary hamartomas, autosomal dominant org) , and . Background Information: The goal is to review the imaging Educational Goals/Teaching Points: The goals are to discuss characteristics of primary sclerosing cholangitis seen on ultra- the pathogenesis of the disorders related with biliary ductal plate sound, CT, MRI, and MRCP that aid in the diagnosis of this malformation and review their clinical significance and to inflammatory disorder of the biliary tract . describe the imaging findings of fibropolicystic liver diseases and biliary atresia . Educational Goals/Teaching Points: The major teaching points are accurate characterization of the multimodality imaging fea- Key Anatomic/Physiologic Issues and Imaging Findings/ tures of primary sclerosing cholangitis . Techniques: CT and MR findings of the different clinical disor- ders related with ductal plate malformation are extensively dis- Key Anatomic/Physiologic Issues and Imaging Findings/ cussed and illustrated with particular emphasis in the findings Techniques: This educational exhibit will utilize case examples of that can assist in the differential diagnosis . primary sclerosing cholangitis to demonstrate the characteristic imaging findings that aid in the diagnosis and monitoring of this Conclusion: Knowledge of these disorders and the differences disease . Ultrasound, CT, MRI, and MRCP will be the primary between is fundamental to the correct diagnosis and proper modalities covered . ERCP will be also addressed . We will review management . the imaging features of a variety of complications associated with primary sclerosing cholangitis .

E148. Cholangiocarcinoma: Diagnosis and Preoperative Conclusion: Primary sclerosing cholangitis is a chronic inflamma- Evaluation with MDCT and Dynamic Contrast-Enhanced MRI tory disorder of the biliary tract . Recognizing the radiographic with Pathologic Correlation findings on multiple modalities is essential in the diagnosis and Rezvani, M.1; Kash, N. 1;Shaaban, A. 1; Olpin, J. 1; Sommers, D. monitoring of patients with this disorder . 1; Woodward, P. 1. University of Utah, Salt Lake City, UT; 2. Texas A & M University, College Station, TX Address correspondence to M. Rezvani (maryam.rezvani@ E150. The Effect of Positive Enteric Contrast Administration hsc.utah.edu) on IV Contrast-Enhanced MDCT in Choledocholithiasis Detection Background Information: This exhibit will familiarize the reader Ajlan, A.; Mesurolle, B.; Stein, L.; Kao, E.; Giovanni , A.; Reinhold, with the MDCT and MRI features of cholangiocarcinoma for accu- C. McGill University Health Centre, Montreal, Canada rate diagnosis with emphasis on pathologic correlation and treat- Address correspondence to A. Ajlan ([email protected]) ment planning . Objective: The objective is to retrospectively asses the accuracy Educational Goals/Teaching Points: Teaching points include: of IV-contrast-enhanced MDCT with and without oral contrast pathophysiology and classification of cholangiocarcinoma; administration in choledocholithiasis detection . imaging surveillance–optimizing MDCT and dynamic contrast-en- hanced MRI protocols; imaging characteristics of cholangiocarci- Materials and Methods: Among 1,580 endoscopic retrograde noma with pathologic correlation, and preoperative imaging eval- cholangiopancreatography (ERCP) studies performed over a uation . three-year period, only patients with portal venous (PV)- enhanced 4- and 64-MDCT examinations acquired within a week Key Anatomic/Physiologic Issues and Imaging Findings/ prior to the ERCP study were selected (n=129) . Of those, only Techniques: Key to understanding the imaging characteristics of patients in whom the entire common bile duct (CBD) length was cholangiocarcinoma and thereby optimizing MDCT and MRI pro- visualized comprised the final study population (n=48, 19 males, tocols is an understanding of the pathologic basis of the disease . 29 females; mean age, 68 years) . We identified two groups Predisposing factors and the patient population requiring surveil- according to the absence (n=31) or presence (n=17) of positive lance is reviewed . Key pathologic features and their correspond- intraduodenal contrast . Section thickness ranged from 1 .25-5 ing imaging findings are illustrated . Advanced imaging techniques mm . Two radiologists, blinded to clinical information and ERCP will be reviewed to optimally visualize tumor and enable accu- results, independently evaluated the CT images . Direct CBD stone rate preoperative evaluation . visualization was assessed according to predefined criteria . The

226 El e c t r o n i c Ex h i b i t s : Gastrointestinal

ERCP findings were used as the standard of reference . A third mechanisms include bradykinin associated vasodilatation and reader retrospectively reviewed all discordant results . The diag- increased vascular permeability, drug induced deficiency of C1 nostic performances of both observers and interobserver agree- esterase and possible induction of auto-antibodies leading to an ment were calculated for both groups . immunologic response resulting in angioedema .

Results: Moderate (0 .55) and good (0 .66) interobserver agree- Conclusion: Angioedema involving the upper airway and oral ments were obtained depending on the presence or absence of cavity is a rare, but known complication of ACE-I . Visceral duodenal contrast, respectively . There were 27 stone-positive and angioedema related to ACE-I without upper aerogastric angioede- 21 stone-negative ERCP studies . Using MDCT, a stone was detect- ma is a rare and less recognized entity . Although there may be ed by at least one of the two observers in 23/27(85%) . The an obvious temporal relationship with initiation of antihyperten- stone size ranged from 3-18 .3 mm (mean=11 .2) . According to sive therapy, symptoms may commence many years into the use the third reader, the major reasons for the false results were vol- of an ACE-I . Optimal management of this entity entails attention ume averaging and stone isoattenuation . A 77-88% sensitivity, to good clinical and history, recognition of common 50-71% specificity and 71-74% accuracy were obtained in the imaging features, a high index of suspicion, and timely discontin- group without positive intraduodenal contrast, vs . 50-80% sensi- uation of the offending medication . tivity, 57-71% specificity and 59-71% accuracy in the group with positive intra-duodenal contrast . With exception of the positive predictive value, all the diagnostic performance parameters E152. Value of CT Enterography in Evaluation of Focal and decreased when assessing the group with positive intraduodenal Diffuse Small Bowel Pathology: A Radiologic-Pathologic contrast . This was more pronounced with the negative predictive Correlation (CME Credit Available) value (71-78% vs . 50-67%) . Gerasymchuk, G.; Sokhandon, F.; Shirkhoda, A. William Beaumont Hospital, Royal Oak, MI Conclusion: PV-enhanced 4- and 64-MDCT have an overall mod- Address correspondence to G. Gerasymchuk ([email protected]) erate diagnostic performance in CBD stone detection . There was a trend to decreasing accuracy with positive intraduodenal con- Background Information: Evaluation of disorders of the small trast . Thus, a normal enhanced MDCT in the context of a suspect- intestine has been notoriously frustrating and difficult due to its ed CBD stone does not exclude the diagnosis and the use of pre- relative inaccessibility to endoscopic evaluation and the poor contrast scans or negative enteric contrast is still recommended sensitivity of barium studies . CT enterography (CTE) is a relatively in such cases . new technique that since its introduction in late 1990s has quick- ly become standard of care for evaluation of small bowel (SB) pathology . It has significantly improved visualization of SB muco- E151. Cross-Sectional Imaging of Angiotensin Converting sa, folds, wall and contents (including focal lesions) . Enzyme Inhibitor Induced Visceral Angioedema: A Case Series and Pictorial Review Educational Goals/Teaching Points: The goals are to discuss Vallurupalli, K.; Coakley, K. Southern Illinois University, Springfield, IL the technique and indications for CTE; to present the normal Address correspondence to K. Vallurupalli ([email protected]) anatomy and abnormal radiographic signs as demonstrated by CTE; to review potential pitfalls; to explain the advantages of CTE Background Information: Abdominal pain of acute onset is one over traditional contrast studies, and to address some concerns of the most common complaints of patients presenting to the and precautions during performing CTE . emergency department (ED) . Visceral angioedema induced by angiotensin converting enzyme inhibitor (ACE-I) is a rare etiology Key Anatomic/Physiologic Issues and Imaging Findings/ of acute onset or intermittent acute abdominal pain .We present Techniques: CTE utilizes a low density oral and IV contrast to the salient CT findings in four patients with ACE-I induced visceral distend the lumen and enhance visualization of the SB wall and angioedema . mucosa . With proper technique and knowledge of imaging appearance of SB pathologies, CTE provides an excellent tool to Educational Goals/Teaching Points: The goals are to describe evaluate the entire SB plus the solid abdominal organs and vas- CT features of visceral angioedema, correlate the imaging find- culature all at the same time . This will help our clinical colleagues ings with patient symptoms and medication history, and recog- to make the diagnosis and planning for treatment without any nize ACE-I induced visceral angioedema as a rare, but reversible need for further tests or invasive procedures in most situations . In cause of acute abdominal pain . review of more than 300 CTEs in our institution, we present many typical as well as unusual cases of SB pathology including, Key Anatomic/Physiologic Issues and Imaging Findings/ but not limited to, new onset, recurrence and complications of Techniques: Examinations were performed with a 64-row MDCT Crohn’s disease (fistulas, abscesses, strictures); partial bowel scanner (Siemens Medical Solutions, Malvern, PA) at 5 mm and obstruction; mesenteric ischemia; infectious and noninfectious 1 .5 mm slice width with multiplanar reformatting in four patients . enteritis; congenital variants; arteriovenous malformation; gas- Imaging characteristics include presence of ascites and mesenter- trointestinal bleed; benign and malignant tumors (adenocarcino- ic edema (n=4) and mural thickening of duodenum and jejunum ma, lymphoma, carcinoid, melanoma, etc ). . Also, we are able to (n=2) and ileum (n=2) . Engorgement of the vasa recta was seen provide surgical and pathological, and in some cases endoscopic in two cases . All patients improved clinically after discontinuation correlation . Additionally, there will be a short discussion on diag- of the ACE-I . Resolution of abnormal findings was documented in nostic approach, patient selection, and frequency in performing two patients on follow up imaging . The actual mechanism of vis- follow up CTE, with the consideration of radiation exposure and ceral angioedema induced by ACE-I remains unknown . Proposed the need for IV contrast . Given the advantages of CTE, we antici-

227 El e c t r o n i c Ex h i b i t s : Gastrointestinal pate that the new modality has a good potential to replace tradi- been postulated to result in various motility disorders in both tional SB barium studies, enteroclysis, staging CT scans, and to pediatric and adult patients . compliment capsule endoscopy in many instances . Educational Goals/Teaching Points: The goals are to discuss Conclusion: Knowledge of standard CTE techniques, normal ana- the central role of the ICC in modulating gut motility; describe tomical appearance of the SB, possible artifacts, and pitfalls as well the spectrum of gastrointestinal disorders linked to abnormalities as radiographic signs of SB diseases and extraintestinal pathology of ICC, and review the cross-sectional imaging findings of non- will help widely integrate the method in general practice . neoplastic entities related to the abnormalities of ICC .

Key Anatomic/Physiologic Issues and Imaging Findings/ E153. Isolated Intestinal and Multivisceral Transplantation: Techniques: Pediatric disorders linked to ICC include idiopathic Radiological Evaluation of the Normal and Abnormal hypertrophic pyloric stenosis, meconium ileus and Hirshsprung’s Transplanted Small Bowel disease . A wide spectrum of adult gut disorders such as achala- Lall, C.; Hoff, A.; Vianna, R.; Fridell, J. Indiana University Medical sia, gastroparesis, chronic idiopathic intestinal pseudo-obstruc- Center, Indianapolis, IN tion, diabetic gastroenteropathy, afferent loop syndrome, and Address correspondence to C. Lall ([email protected]) Chagas disease are hypothesized to be related to abnormal ICC morphology and/or function . Cross-sectional and projectional Background Information: This exhibit will discuss indications imaging findings of adult and pediatric disorders of ICC will be for small bowel transplantation and the role of new immunosup- discussed . pressive agents; describe the latest surgical techniques used in intestinal and multivisceral transplantation; describe the unique Conclusion: ICC play an important role in gut motility . cross-sectional imaging appearance of the normal transplanted Abnormalities of ICC may lead to a gamut of motility disorders in bowel, and discuss imaging of the abnormal intestinal transplant pediatric and adult patients . Many of these disorders have specif- and unique complications in this subgroup . ic imaging findings that help in diagnosis and management .

Educational Goals/Teaching Points: This exhibit will discuss types of intestinal transplantation, including isolated intestinal E155. Small Bowel Imaging: Have We Overcome the transplant, intestinal-liver and multivisceral transplantation and Challenge? A Review of MDCT Appearances of Small Bowel surgical techniques in the donor and recipient; new aspects of Pathology immunosuppression and breakthrough agents, and unique nor- Mumtaz, H.1; Kalra, N.1; Khandelwal, N.1; Choudhary, S.2; mal appearances of transplanted bowel on cross-sectional imag- Sunnapwar, A.2 1. Post Graduate Institute of Medical Education ing in view of lack of lymphatics and neural innervations . It will and Research, Chandigarh, India; 2. University of Texas Health illustrate appearances of the abnormal intestinal transplant and Science Center–San Antonio, San Antonio, TX unique complications in this group after transplantation . Address correspondence to S. Choudhary ([email protected])

Key Anatomic/Physiologic Issues and Imaging Findings/ Background Information: A few years ago small bowel follow Techniques: The exhibit will discuss CT imaging and CT enterocl- through (SBFT) was the primary and only method for evaluation ysis of intestinal transplantation and unique appearance of trans- of diseases of the small bowel, which also remained inaccessible planted small bowel, and illustrate unique complications that to the traditional endoscope . However with the introduction of beset this transplant population and appearances of the abnor- the MDCT, imaging of the small bowel has undergone a para- mal transplanted small bowel . digm shift . Faster acquisition of a large volume of data with thin collimation with use of MDCT allows multiplanar reformatting as Conclusion: This exhibit will illustrate the unique imag- well as use of multiple enhancement phases after intravenous ing appearance of transplanted small bowel as well as specific contrast administration . MDCT has the advantage of being the complications like rejection, infection, post-transplantation lym- one step modality for diagnosis of common as well as uncom- phoproliferative disorder and graft-versus-host disease among mon bowel pathologies as it can evaluate not only the lumen others . It will discuss advancements in the field of intestinal but also the wall, extramural changes, mesentery, nodes as well transplantation and future developments in this field and discuss as the vasculature . refinement in surgical techniques and the latest aspects of immu- nosuppression as well as experience in living related intestinal Educational Goals/Teaching Points: The goals are to give an transplantation . update on the current protocols and techniques of MDCT of the small bowel including the CT enteroclysis; provide a brief over- view of various pathologies involving the small bowel . The E154. Non-Neoplastic Disorders of the Interstitial Cells of pathologies can be classified as: congenital, inflammatory, infec- Cajal: A Comprehensive Review tious, malabsorption syndromes, vascular, post-traumatic and Katabathina, V.; Nagar, A.; Prasad, S.; Choudhary, S.; Ojili, V.; neoplastic; review the radiological imaging features of various Chintapalli, K. University of Texas Health Science Center at San pathologies affecting the small bowel, and emphasize the distinc- Antonio, San Antonia, TX tive radiological patterns and an algorithmic approach that may Address correspondence to V. Katabathina ([email protected]) help distinguish specific entities .

Background Information: Interstitial cells of cajal (ICC), found Key Anatomic/Physiologic Issues and Imaging Findings/ in the walls of the gastrointestinal tract, are thought to play an Techniques: With the advent of MDCT, imaging of the small important role in gut neurotransmission and pacemaker activity . bowel has undergone a major change . The important advantages Abnormalities of ICC (decrease in cell number or function) have of CT over the traditional small bowel follow through include 228 El e c t r o n i c Ex h i b i t s : Gastrointestinal evaluation of not only the lumen but also the wall, extramural Key Anatomic/Physiologic Issues and Imaging Findings/ changes, mesentery, nodes as well as the vasculature . Techniques: The increased utilization of MDCT has made post- processing MPR a quick, efficient, and useful adjunctive imaging Conclusion: Early detection of small bowel pathologies is desira- strategy in diagnostic imaging . This is an especially useful tool in ble for the clinicians but challenging for the radiologists . MDCT, the evaluation of small bowel obstructions . Accurately identifying with high sensitivity and specificity, is becoming the one step a transition point or multiple transition points provides useful imaging modality for evaluation of the small bowel . Various information to the surgeon in operative cases . By maximizing the pathologies show characteristic radiologic features that allow us ability of MDCT to reformat the bowel in different planes quickly to establish a specific diagnosis with confidence and an unneces- and efficiently, transition points and potential causes of small sary biopsy or surgery can be avoided . bowel obstruction can be identified with increased accuracy and diagnostic confidence .

E156. CT Significance of Bowel Wall Thickening Conclusion: MDCT and MPR reformations of the bowel in differ- Saenz, R.1,2; Rucks, A.1; Patel, A.1 1. Botsford Hospital, ent planes allow quick and efficient identification of transition Farmington Hills, MI; 2. Michigan State University, Lansing, MI points and potential etiology of small bowel obstructions, other- Address correspondence to R. Saenz ([email protected]) wise often obscured in standard axial planes .

Background Information: During CT studies, bowel wall thick- ening is often seen . There are many different etiologies of this E158. Spectrum of Small Bowel Masses on CT Enterography finding . Clinically, the signs and symptoms of abdominal pain are and CT Enteroclysis (CME Credit Available) overlapping . Therefore, it is often the radiologist that diagnoses Ruan, D.; Hough, D.; Fidler, J.; Barlow, J.; Trenkner, S.; Fletcher, J.; the pathologic process as involving the gastrointestinal tract . Huprich, J. Mayo Clinic, Rochester, MN Address correspondence to D. Ruan ([email protected]) Educational Goals/Teaching Points: The exhibit will review the CT findings of bowel wall thickening in order to allow the radiol- Background Information: CT enterography and CT enteroclysis ogist to understand its significance and discriminate certain etiol- have recently emerged as alternative techniques to image the ogies . Persons who view this exhibit will be able to recognize the small bowel . Traditional methods of small bowel imaging are key CT findings; review clinical and pathological relevant informa- suboptimal . Conventional CT suffers from lack of small bowel dis- tion related to the diagnoses of bowel wall thickening, and tension whereas fluoroscopic techniques provide limited informa- improve overall CT diagnostic ability . tion . CT enterography and CT enteroclysis address these limita- tions . In this essay, we discuss the advantages and limitations of Key Anatomic/Physiologic Issues and Imaging Findings/ these new techniques . We also present a pictorial review of small Techniques: Multiple cases will be reviewed utilizing CT . bowel masses and how these masses can be optimally imaged . Correlation will be made with the imaging findings and the EGD, colonoscopy, and biopsy results . Educational Goals/Teaching Points: The exhibit will review CT enterography and CT enteroclysis techniques; highlight advantag- Conclusion: Bowel wall thickening is an important CT finding . es and limitations of these techniques for detection of small Many different etiologies exist . At times, it is possible for the radi- bowel masses, and illustrate the spectrum of small bowel pathol- ologist to narrow the differential diagnosis based on the specific ogy identified using these techniques . CT findings of the wall thickening . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: CT enterography and CT enteroclysis differ from E157. Bowel Transit Delay? Switch Planes! Utilizing MDCT conventional CT in that better luminal distention is achieved . Two and Multiplanar Reformations to Identify Transition Points different types of enteric agents are available: neutral and posi- in Small Bowel Obstruction (CME Credit Available) tive . The enteric agent used should be chosen based on clinical Goud, A.; Goud, N.; Jati, A.; Manuel, D. VA Boston Healthcare indication to improve contrast between bowel lumen and mass . System, Boston, MA Neutral contrast agents are useful for detecting hypervascular Address correspondence to A. Goud ([email protected]) masses whereas positive contrast agents may improve detection of minimally enhancing masses . We performed a retrospective Background Information: The goal is to demonstrate the use- search of our radiology and pathology databases for patients fulness of multiplanar reformations (MPR) and MDCT capability with small bowel masses shown on CT enterography and CT as a quick and effective way to identify transition points in cases enteroclysis . Imaged small bowel masses included adenocarcino- of small-bowel obstruction (SBO) . ma, gastrointestinal stromal tumor, carcinoid tumor, metastasis, lymphoma, paraganglioma, vascular malformation, polyp, and Educational Goals/Teaching Points: The exhibit will review the lipoma . Representative images are selected to illustrate typical indications MPR in cases of small bowel obstruction; demon- imaging features for each . Special focus will be made upon those strate the usefulness of MPR in identifying transition points cases that illustrate the specific advantages (luminal distension obscured in the standard axial plane; review the findings of and enteric agent choice) that these new techniques confer . MDCT findings of small bowel obstruction; review the potential causes of SBO and surgical implications, and discuss how to opti- Conclusion: Recent advances in small bowel imaging address mize your report: A checklist for including useful and critical key the limitations of conventional CT with imaging of the small points in cases of small bowel obstruction for our surgical col- bowel . Knowledge of these new techniques will help the radiolo- leagues . gist to improve detection and characterization of small bowel masses . 229 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E159. CT Enterography vs. Fluoroscopic Small Bowel Follow- complementary imaging modalities and image-guided biopsy in Through in Inflammatory Bowel Disease: Is CT Enterography expediting a prompt tissue diagnosis . up to the Task? (CME Credit Available) Shin, K.; Ho, C.; Stay, R.; Carr, T.; Choudhri, A.; Lambert, D. Key Anatomic/Physiologic Issues and Imaging Findings/ University of Virginia, Charlottesville, VA Techniques: Abdominal involvement predominates at presenta- Address correspondence to C. Ho ([email protected]) tion in the nonendemic variants . Pathologic and imaging findings range from discrete bowel wall thickening to diffuse soft tissue Background Information: The mainstay for the evaluation of and organ infiltration . Despite its diverse appearance, BL demon- the features and complications of inflammatory bowel disease strates some characteristic sites of involvement (terminal ileum (IBD) has been fluoroscopic examination . With improvements in and mesentery) and appearance (nephromegaly) The. relative CT technique and availability, CT enterography (CTE) has become prevalence of BL is amplified in children and immune-compro- a viable option for the evaluation of inflammatory bowel disease . mised patients . BL is a highly aggressive malignancy, character- This presentation will compare and correlate CTE and small ized by rapid doubling time with prognosis dictated by the bur- bowel follow-through (SBFT) findings of IBD in a group of den of disease at presentation . BL demonstrates a dramatic patients receiving both examinations . response to chemotherapy . Early diagnosis, aided by imaging- guided biopsy techniques, and prompt management yield high Educational Goals/Teaching Points: The exhibit will review CTE remission and overall survival rates . technique and protocol ; discuss both CTE and SBFT findings and complications of IBD, and give a retrospective comparison and Conclusion: BL is a highly aggressive form of NHL with a predi- review of findings in patients who have undergone both CTE and lection for intra-abdominal and extranodal involvement . Although SBFT examinations . there is no one finding diagnostic of BL, familiarity with its com- mon and diverse radiological manifestations, as well as its Key Anatomic/Physiologic Issues and Imaging Findings/ aggressive clinical behavior, will enable prompt diagnosis and Techniques: CTE is comparable to SBFT in identifying findings of management of this potentially curable malignancy . IBD . Over a two-year period, 112 CTE studies were performed at our institution with 41 of the patients having had recent compari- son small bowel fluoroscopic examinations . CTE is able to deline- E161. Small Bowel Perforation: Differential Diagnosis and ate secondary findings and complications of IBD such as fistulas, Spectrum of CT Findings abscesses, perienteric inflammation, and strictures, some of Duncan, D.1; Wattamwar, A.2; Hines, J.1; Katz, D.2; Friedman, B.1 which are not detectable on SBFT . 1. Long Island Jewish Medical Center, Glen Oaks, NY; 2. Winthrop University Hospital, Mineola, NY Conclusion: CT enterography can be a stand-alone or comple- Address correspondence to D. Duncan ([email protected]) mentary tool in the evaluation of patients with inflammatory bowel disease . Because of its cross-sectional nature, CTE can Background Information: Small bowel perforation is an infre- identify additional secondary findings and complications of IBD quently encountered entity during abdominal imaging . The goal that can be difficult or impossible to identify on SBFT exams . of this exhibit will be to exemplify, using CT examples, the vari- ous pathological states which ultimately result in small bowel perforation . E160. Imaging Intra-Abdominal Burkitt Lymphoma: From Discrete Bowel Wall Thickening to Diffuse Soft Tissue Educational Goals/Teaching Points: CT combined with history Infiltration can often define the site and etiology of small bowel perforation . Martin, N.; Harris, A.; Chang, S. University of British Columbia, CT examinations will be utilized to demonstrate small bowel per- Vancouver, Canada forations which can occur as the result of: anastomotic leak, Address correspondence to N. Martin (nancyma@interchange. Crohn’s disease, diverticular disease, foreign body, iatrogenic, ubc.ca) ischemia, malignancy, and trauma .

Background Information: Burkitt lymphoma (BL) is a highly Conclusion: At the conclusion of this presentation the partici- aggressive lymphoproliferative malignancy classified under the pant should be able to provide a comprehensive differential diag- WHO umbrella of non-Hodgkin lymphomas (NHL) . Intra- nosis and be able to identify the CT findings associated with abdominal involvement is extremely common, and demonstrates small bowel perforation . the NHL predilection for extranodal involvement, reflected in a broad spectrum of clinicopathology . The purpose of this exhibit is to increase awareness of the clinical and imaging manifestations E162. Fistulizing Crohn’s Disease: Correlation Between of intra-abdominal BL, enabling early suspicion and an expedited MDCT Enterography and Surgical Findings (CME Credit tissue diagnosis . Available) Ballester, G.; Labat, E.; Badillo, K.; Colon, E.; Gomez, A.; Lopez- Educational Goals/Teaching Points: The exhibit will define BL Alvarez, Y. University of Puerto Rico, Guaynabo, PR within the WHO lymphoma classification system; briefly describe Address correspondence to G. Ballester ([email protected]) the subclassification of BL; review the clinicopathology of BL, with emphasis on sporadic and immunodeficiency variants and Background Information: Crohn’s disease is a chronic inflam- their intra-abdominal presentation; review the spectrum of intra- matory condition of unknown etiology, which may involve any abdominal BL, with sample cases illustrating solid organ, bowel, part of the gastrointestinal tract . Transmural inflammation extend- and soft tissue (ST) involvement, and briefly discuss the role of ing into adjacent bowel and organs through fistulous tracts is one

230 El e c t r o n i c Ex h i b i t s : Gastrointestinal of the most common complications in Crohn’s disease . The radiographs, ultrasound, CT and MRI . Identification of pathogno- cumulative risk for fistulas in patients with Crohn’s disease is 33% monic features of mesenteric ischemia such as pneumatosis and after 10 years and 50% after 20 years . The location and severity portal venous gas on abdominal radiographs, ultrasound and CT of fistulous disease is critical in determining treatment . MDCT scan will be discussed with examples . Identification of other signs enterography is an excellent tool for this purpose . Small fistulas of early mesenteric ischemia such as subtle bowel wall thickening are first treated medically . On the other hand, large or multiple and decreased enhancement will be discussed . Technique of CT fistulas, may need surgical treatment, particularly if they are angiography and MR angiography and their value in diagnosing accompanied by persistent symptoms, such as fever or abdominal acute and chronic mesenteric ischemia will be discussed . pain or if they are related to abscess formation . The purpose of Potential pitfalls in diagnosing mesenteric ischemia will be dis- this exhibit is: to describe an optimal protocol for MDCT enterog- cussed including nonischemic causes of bowel wall thickening, raphy; to understand the utility of MDCT enterography for the benign causes of pneumatosis and portal venous gas and mimics diagnosis of fistulizing Crohn’s disease, and to correlate the tom- of pneumatosis on abdominal radiographs and CT scan . ographic findings of fistulizing Crohn’s with the surgical findings . Conclusion: Radiologists should be able to identify the manifes- Educational Goals/Teaching Points: Fistulas are a common tations of mesenteric ischemia on all imaging modalities to make complication of Crohn’s disease . MDCT enterography plays a an accurate diagnosis to aid proper patient management . There major role in the diagnosis of fistulizing Crohn’s disease, provid- are also several potential pitfalls in diagnosing mesenteric ing great benefit for surgical planning . ischemia which radiologists should be aware of to avoid a misdi- agnosis of mesenteric ischemia as well . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: We will review the pathophysiology of Crohn’s dis- ease; describe MDCT enterography protocol in the evaluation of E164. Variants of Gastric Carcinoma and its Mimicking Crohn’s disease, and will discuss pitfalls in the diagnosis of fistu- Diseases lizing Crohn’s disease . We will also describe the different types of Cho, O.; Kim, Y.; Jeong, W.; Song, S.; Koh, B.; Cho, Y. Hanyang surgery available for patients with Crohn’s disease, including stric- University Kuri Hospital, Kuri City, Kyunggido, South Korea tureplasty, small bowel resection and colectomy . Cases of fistuliz- Address correspondence to Y. Kim ([email protected]) ing Crohn’s disease with surgical correlation will be presented . Background Information: Usually gastric lesions are detected as Conclusion: MDCT enterography has become a very important wall thickening on the CT scans . Gastric wall thickening is nonspe- tool in the evaluation of Crohn’s disease . Radiologists play a cific to diagnosis of specific disease . Most common gastric wall major role in the diagnosis of the disease and its complications, thickenings are adenocarcinoma in malignant disease . However, including fistulizing disease . Therefore, their recognition and dem- variant carcinoma and other tumor mimicking diseases are occa- onstration in MDCT is paramount for the management of patients sionally encountered . These diseases are very different from prog- with this condition . Patients with Crohn’s disease need a multidis- nosis and treatment each other . We illustrate differential diagnos- ciplinary approach, with close collaboration between radiologists, tic points and characteristic CT findings of these diseases . gastroenterologists and surgeons for the accurate assessment and management of the disease and its complications . Educational Goals/Teaching Points: The goals are to review the clinical and radiologic characteristics of gastric carcinoma classified by its variants, and to discuss the differences between E163. Diagnosis of Mesenteric Ischemia: Pearls and Pitfalls these gastric carcinomas, and to distinguish between these gas- (CME Credit Available) tric carcinomas and some diseases which mimic them . Wasnik, A.1; Kaza, R.1; Surabhi, V.2; Al-Hawary, M.1; Liu, P.1 1. University of Michigan, Ann Arbor, MI; 2. University of Texas Key Anatomic/Physiologic Issues and Imaging Findings/ Medical School at Houston, Houston, TX Techniques: We reviewed MDCT and pathologic findings of typi- Address correspondence to R. Kaza ([email protected]) cal gastric adenocarcinoma . We correlated MDCT findings of vari- ants of gastric carcinoma (mucin producing adenocarcinoma, Background Information: Diagnosis of mesenteric ischemia in squamous carcinoma, hepatoid adenocarcinoma, lymphoepitheli- patients presenting with nonspecific abdominal pain is a chal- al carcinoma and carcinoid tumor) and the mimicking diseases of lenge to the radiologist . The early detection of subtle signs helps gastric carcinoma (lymphoma, stromal tumor, gastric metastasis, in correct patient management . At the same time there are sever- metastasis adjacent to stomach, severe gastritis, tuberculous gas- al pitfalls which one should avoid in making a misdiagnosis of tritis, and parasite infestation) on the pathologic basis . mesenteric ischemia . Conclusion: It is possible to know the clinical and radiologic key Educational Goals/Teaching Points: The goal is for the learner points that explain each variant . It is also possible to discriminate to make a correct and confident diagnosis of mesenteric other diseases from gastric carcinomas to make a correct treat- ischemia on all imaging modalities and be able to identify the ment plan . mimics of mesenteric ischemia to avoid a wrong diagnosis of mesenteric ischemia .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The etiology and pathophysiology of mesenteric ischemia will be discussed . Role of imaging in diagnosing mesenteric ischemia will be discussed with findings on abdominal

231 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E165. Imaging Manifestations and Mimics of Ischemic trends in interpretation of the imaging findings . The major teach- Bowel (CME Credit Available) ing points of this exhibit are: 1 . CTE can be easily performed with Murphy, G.; Beddy, P.; Knox, M.; Keogan, M.; Wilson, G. St. modern equipment . 2 . When CTE is performed appropriately, it is James’s Hospital, Dublin, Ireland a powerful tool capable of characterizing small bowel pathology, Address correspondence to G. Murphy (gillianmurphy78@hotmail. identifying lesions within the stomach, duodenum and colon, com) and providing an opportunity to evaluate both the extraluminal and extraintestinal tissues . The exhibit will also provide a review Background Information: Ischemic bowel is caused by insuffi- of the recent trends in interpretation of the imaging findings; for cient blood flow to the bowel and ranges from localized transient example diagnosing the active component of Crohn’s disease . ischemia to catastrophic necrosis of the gastrointestinal tract . MDCT with the benefit of multiplanar reconstruction is the most Key Anatomic/Physiologic Issues and Imaging Findings/ commonly used modality for this diagnosis . However, as CT find- Techniques: The exhibit begins with a short introduction of CTE ings in ischemic bowel are nonspecific and variable, the diagno- followed by discussion of the imaging parameters, patient prepa- sis of ischemic bowel provides a challenge for radiologists . This ration, and types of negative oral contrast . We then discuss the exhibit reviews patients with a CT diagnosis of ischemic bowel utility of CTE in diagnosing various gastrointestinal diseases and from January to December, 2007 outlining positive and false pos- review the imaging findings according to the recent trends in itive imaging findings . interpretation . The exhibit concludes with sample cases illustrat- ing the diagnostic role of CTE and imaging findings of a spectrum Educational Goals/Teaching Points: The goals are to review of diseases including inflammatory bowel disease, mesenteric the pathophysiology of ischemic bowel; illustrate the common ischemia, gastrointestinal bleeding, small bowel obstruction, and imaging manifestations of ischemic bowel; present imaging find- gastrointestinal tumors . ings of ischemic bowel based of a series of 50 patients, and pro- vide examples of mimics of ischemic bowel emphasizing the Conclusion: CTE can be easily performed with modern equip- challenge this diagnosis presents to radiologists . ment and, when performed appropriately, is a powerful tool capable of characterizing small bowel pathology, identifying Key Anatomic/Physiologic Issues and Imaging Findings/ lesions within the stomach, duodenum and colon, and providing Techniques: Plain films of the abdomen demonstrate the non- an opportunity to evaluate both extraluminal and extraintestinal specific findings in early bowel ischemia . The CT imaging findings tissues . Radiologists need to be able to recognize and interpret of ischemic bowel include: bowel wall thickening with or without the relevant findings in CTE and apply them to the various gas- the target sign; intramural pneumatosis; mesenteric or portal trointestinal diseases . venous gas; mesenteric arterial or venous thromboembolism; engorgement of mesenteric veins and mesenteric edema; lack of bowel wall enhancement; increased enhancement of the thick- E167. Duodenal Abnormalities at MR Small-Bowel Follow- ened bowel wall; bowel obstruction, and infarction of other Through abdominal organs . Cronin, C.; Lohan, D.; DeLappe, E.; Roche, C.; Murphy, J. University College Hospital Galway, Galway, Ireland Conclusion: This comprehensive case series illustrates the spec- Address correspondence to C. Cronin (carmelcronin2000@hot- trum of imaging findings of ischemic bowel and highlights mim- mail.com) ics of this diagnosis . Background Information: Cross-sectional characterization of duodenal pathology is plagued with inadequacy, a reflection of E166. Computed Tomographic Enterography: Principles and the meandering course of this segment . We consider the imaging Recent Interpretation Trends of Imaging Findings (CME appearance of such pathology at MR small bowel follow-through Credit Available) (MRSBFT), illustrating the typical manifestations of each patho- Elsayes, K.; Al-Hawary, M.; Platt, J. University of Michigan, Ann logically-confirmed condition . Arbor, MI Address correspondence to K. Elsayes ([email protected]) Educational Goals/Teaching Points: Many of the duodenal pathologies we illustrate were found incidentally, reminding us Background Information: Recent improvements in computed not to forget the duodenum and highlighting the need for a thor- tomographic enterography (CTE) technique have increased its ough assessment . Undoubtedly many of the duodenal patholo- utility as an effective, efficient, and noninvasive tool aiding in the gies are well known to the reader; however we consider the diagnosis and management of a variety of gastrointestinal disor- imaging manifestations at MRSBFT, illustrating features that may ders . As more and more CTE examinations are performed, it is aid in their differentiation . Such a description has not previously important to be able to recognize and interpret the relevant been undertaken, making this a valuable addition to the current imaging findings as they pertain to various gastrointestinal dis- literature . eases . Key Anatomic/Physiologic Issues and Imaging Findings/ Educational Goals/Teaching Points: The exhibit will describe Techniques: Through our institutional experience and a review the imaging techniques of CTE; describe the clinical indications of literature we will provide a diverse review of MRSBFT’s role in for CTE; discuss the clinical utility of CTE in diagnosis of various duodenal disease diagnosis and management . We will provide a gastrointestinal diseases; and illustrate the imaging characteristics thorough, informative and concise guide . of these diseases . Special emphasis will be placed on the recent

232 El e c t r o n i c Ex h i b i t s : Gastrointestinal

Conclusion: MRSBFT allows confident duodenal evaluation intrinsic contrast resolution, faster imaging times, and decreased owing to a combination of sufficient luminal distension and mul- artifacts . MRI can suppress intra-abdominal fat signal, expand the tiplanar versatility . Diseases of the duodenum may have a variety dynamic range of abdominal tissue signal intensities, and distin- of manifestations at MRSBFT, a knowledge of which may aid in guish between intraluminal bowel contents and the bowel wall . confident noninvasive patient diagnosis . Educational Goals/Teaching Points: Persons who view the exhibit will be able to define the comprehensive protocol used E168. Evaluation of Crohn’s Disease In The Era of Radiation for bowel imaging on MRI, including methods for rapid imaging, Saftey: MR Enterography Technique and Spectrum of timing of postgadolinium sequences, and bowel preparation and Disease distension; understand the anatomical involvement of the bowel Grand, D.; Shah, S.; Beland, M.; Mayo-Smith, W. Warren Alpert wall and identify the involved segments of bowel . Differentiate School of Medicine/Brown University, Providence, RI mucosal/submucosal involvement from transmural disease on Address correspondence to D. Grand ([email protected]) unenhanced and enhanced sequences; differentiate acute dis- ease from chronic processes, and identify complications of Background Information: The purpose of this exhibit is to inflammatory processes, including abscesses and fistulae . describe the technique and demonstrate the feasibility and effi- cacy of evaluation of patients with known or suspected Crohn’s Key Anatomic/Physiologic Issues and Imaging Findings/ disease using MR enterography . First, we demonstrate the tech- Techniques: Applications of MRI in the evaluation of bowel wall nique of MR enterography including the rationale for each thickening include diagnosing and monitoring severity of inflam- sequence, optimized protocols for bowel distension with oral matory bowel disease, including the identification of acute dis- contrast and mucosal enhancement with intravenous contrast . ease from chronic inflammation; diagnosing inflammatory proc- Additionally, we demonstrate the spectrum of Crohn’s disease as esses such as enteritis, appendicitis, diverticulitis; identifying visualized on MR enterography from varying degrees of active enteric abscesses and fistulae; depicting abnormalities in the small bowel inflammation, colonic disease, skip lesions, fistulae arterial supply and venous outflow of the bowel with unen- and abscess formation and differentiation of chronic from active hanced and postgadolinium sequences; and elucidating the changes . source and extent of neoplastic disease . Acute inflammation alters the appearance of the bowel wall, fat and mesentery Educational Goals/Teaching Points: The exhibit will focus on : around the abdominal bowel on fat suppressed T2 sequences . 1) Technique—coil choice and positioning, scan coverage, pulse Chronic disease will demonstrate progressive enhancement after sequences, oral contrast protocol, and IV contrast protocol; intravenous gadolinium but without a similar degree of T2 signal 2) Spectrum of Disease—active inflammation (terminal ileitis – change . MRI is well suited for directing therapeutic management mild, moderate, severe; skip lesions; colonic disease); chronic of patients with Crohn’s disease and complements the informa- inflammation (differentiation from active disease; stricture forma- tion derived from endoscopy . tion); and complications (fistula formation; abscess) and 3) Future Directions—real-time cine bowel imaging and monitoring Conclusion: With the implementation of modern MRI techniques response to new immunomodulatory therapies . in bowel imaging, bowel wall thickening can be reliably depicted . The differential diagnosis, which runs the gamut of inflammatory, Key Anatomic/Physiologic Issues and Imaging Findings/ infectious, ischemic, and neoplastic diseases, can be narrowed Techniques: This exhibit illustrates the technique of small bowel based on pertinent positive and negative MRI findings . MRI for the detection and characterization of changes of inflam- Furthermore, the ability of MRI to identify acute processes is vital matory bowel disease, an exquisitely sensitive technique without to formulating the optimal treatment plan and assessing ionizing radiation . response to therapy .

Conclusion: MR enterography is technically feasible and effica- cious for routine evaluation of the full spectrum of pathology in E170. Normal Small Bowel Wall Characteristics on MR Small patients with Crohn’s disease without exposure to ionizing radia- Bowel Follow-Through tion . As readers become more comfortable with the techniques Cronin, C.; DeLappe, E.; Lohan, D.; Roche, C.; Murphy, J. University and appearances presented in this educational exhibit, we College Hospital Galway, Galway, Ireland believe MR enterography may replace fluoroscopy and CT in the Address correspondence to C. Cronin (carmelcronin2000@hot- evaluation of Crohn’s disease . mail.com)

Objective: The objective was to assess the normal small bowel E169. Demystifying Bowel Wall Thickening With MRI (CME parameters, namely bowel diameter, bowel wall thickness, Credit Available) number of folds (valvulae connivientes) per 2 5. cm (inch), fold Krishnamoorthy, S.; Sebastian, S.; Kalb, B.; Rostad, B.; Li, J.; thickness and interfold distance per small bowel segment (duo- Salman, K.; Sitaraman, S.; Sarmiento, J.; Martin, D. Emory denum, jejunum, proximal ileum, distal ileum and terminal University, Atlanta, GA ileum) on MR small bowel follow-through/enterography . Address correspondence to S. Krishnamoorthy (saravanan. [email protected]) Materials and Methods: Between September, 2003 and January, 2008, 280 MR small bowel follow-through examinations Background Information: Bowel wall thickening is a commonly were performed for investigation of known or suspected small encountered question in clinical practice . Advances in MRI have bowel pathology . A total of 120 of these examinations were nor- allowed for detailed visualization of the bowel due to improved mal . Sixty-five (29 males, 36 females, mean age=34years,

233 El e c t r o n i c Ex h i b i t s : Gastrointestinal range=17-73years) of 120 examinations without a prior small 3) CT examinations (standard, CT enterography, and CT enterocl- bowel diagnosis, with no prior or subsequent abnormal radiology ysis; and 4) MR methods (same as the CT categories) . The basic or endoscopy examinations, no prior small bowel surgery and techniques of these radiologic studies are discussed and normal with a minimum three years follow-up demonstrating normality examinations presented . Also, common causes of SBO seen on were retrospectively evaluated for the described small bowel radiologic imaging are illustrated . The advantages and limitations parameters . of radiologic imaging relative to the methods used are outlined . Finally, recommendations are made regarding selecting one or Results: We found the mean diameter of the duodenum to be more imaging studies for assessing specific clinical problems . 24 .8 mm (SD=4 .5 mm), jejunum to be 24 .5 mm (SD=4 .2 mm), proximal ileum to be 19 5. mm (SD=3 6. mm), distal ileum to be Conclusion: SBO remains a common problem . Radiologic imag- 18 9. mm (SD=4 2. mm) and terminal ileum to be 18 7. mm ing of the SB has expanded exponentially in recent years, and (SD=3 .6 mm) . The number of folds per 2 .5 cm varied from 4 6. in selecting a specific imaging examination has become more diffi- the jejunum to 1 .5 in the terminal ileum . The fold thickness var- cult . This exhibit will hopefully update and clarify this selection ied from 2 1. mm in the duodenum to 1 8. mm in the terminal process . ileum . The small bowel parameters gradually decreased in size from the duodenum to the smallest measurements which were in the terminal ileum . The bowel wall is similar in size through- E174. The Usefulness of MRI in the Evaluation of Acute out the small bowel measuring 1 .5 mm +/-0 .5 mm . Sigmoid Diverticulitis Halpenny, D.; McNeill, G.; Snow, A.; Buckley, O.; Geoghegan, T.; Conclusion: These results provide the mean, range of normality Torreggiani, W. Adelaide + Meath Hospitals Incorporating the and standard deviation of the small bowel parameters per seg- National Childrens Hospital, Dublin, Ireland ment on the current population on MR Small bowel follow Address correspondence to D. Halpenny (darraghhalpenny@hot- through . From our experience, knowledge of these parameters is mail.com) extremely helpful and essential in the everyday assessment of MR small bowel follow through studies . Objective: The aim of the study was to evaluate the usefulness of MRI in the detection and characterization of acute sigmoid diverticulitis . E171. Small Bowel Obstruction: Radiologic Evaluation and Imaging Selection (CME Credit Available) Materials and Methods: Twenty-six patients (15 women, 11 Caserta, M.; Ott, D.; Oliphant, M.; Leyendecker, J. Wake Forest men; mean age 58 years, range 42-74) with acute sigmoid diver- University Medical Center, Winston Salem, NC ticulitis diagnosed at CT, underwent MR imaging . The examina- Address correspondence to D. Ott ([email protected]) tions were evaluated independently by two radiologists on a monitor in a PACS (Siemens Medical Solutions, Forchheim, Background Information: Small bowel obstruction (SBO) Germany) environment . Each radiologist attempted to identify the remains a common clinical problem, which is difficult to diag- features of diverticulitis and grade the severity of disease on both nose accurately and to decide on a treatment option . Plain film CT and MRI at different sittings . Results were recorded on coded imaging is still performed often as the initial examination, but forms which were entered in a computerized database . The data has low specificity in distinguishing functional vs . mechanical was statistically analysed using SPSS software . Correlation analysis obstruction, and a diagnostic accuracy of only 50%-60% . was performed with Speaman’s rank correlation coefficient . The Traditional peroral contrast studies of the small bowel (SB) often inter-rater agreement was measured with Cohen’s kappa test for provide little improvement in accuracy; however, enteroclysis each imaging modality between the two observers . with intubated ‘large volume’ infusion of the SB provides a much more accurate examination . In more recent years, both CT and Results: The sensitivity of MRI for diagnosing acute diverticulitis MR have been applied to the evaluation of SBO; these tech- MRI was 100% and specificity was 100% . The relative sensitivity niques can be perform using ‘standard’ methods or with a vol- of MRI for diagnosing the severity of diverticulitis was derived; ume challenge as enterography or enteroclysis variations . Thus, 93 5%. for mild disease, 41 5%. for moderate disease and 50% current imaging assessment of SBO has changed and expanded for severe disease . The correlation between CT and MRI was ana- dramatically, and clinicians and radiologists must be aware of lyzed using Speaman’s rank correlation coefficient . The ρ (rho) these various options and choose appropriately . value was 0 .73 with p<0 01. which was statistically significant, demonstrating good correlation between CT and MRI in the diag- Educational Goals/Teaching Points: The goals are to provide a nosis of acute diverticular disease . The reliability or internal con- clinical overview of the current etiology and status of SBO; dis- sistency of each imaging modality (CT and MRI) was assessed cuss the various imaging options now available for evaluating the with the Cronback alpha (a) test between the two observers . The SB; review and illustrate the advantages and limitations of these a value for CT was 0 84,. the a value for MRI was 0 75. . Each of imaging methods, and outline algorithms for specific clinical the a values is statistically significant implying that both imaging presentations and imaging recommendations . modalities are reliable in diagnosing acute diverticulitis . The inter- rater agreement was measured with Cohen’s kappa test for each Key Anatomic/Physiologic Issues and Imaging Findings/ imaging modality between the two observers . The kappa value Techniques: In this exhibit, the current clinical status of SBO for CT was 0 44,. considered significant; the kappa value for MRI regarding etiology, clinical assessment, and potential treatment was 0 549,. considered highly significant . There was higher agree- options are first reviewed . The various imaging modalities for ment between the observers when MRI was used to assess evaluating SBO are presented, and include: 1) plain abdominal patients with acute diverticulitis . imaging; 2) SB contrast studies (both peroral and enteroclysis);

234 El e c t r o n i c Ex h i b i t s : Gastrointestinal

Conclusion: This comparative study of CT and MR demonstrates E176. Can CT Replace MRI in Preoperative Assessment of that MRI is a fast, safe and accurate imaging modality for diag- the Circumferential Resection Margin in Rectal Cancer? nosing acute sigmoid diverticulitis, with a sensitivity and specifici- Maizlin, Z.1; Brown, J.2; So, G.1; Phang, T.2; Brown, C.2; Kirby, J.1; ty of 100% in comparison to the “gold-standard” CT . MRI may Walker, M.1; Maizels, L.3; Coblentz, C.1; Vora, P.1; Tiwari, P.2 1. provide an alternative to CT in this clinical setting when CT can- McMaster University Medical Centre, Burlington, Canada; 2. St. not be performed . Paul’s Hospital, Vancouver, Canada; 3. Technion, Haifa, Israel Address correspondence to Z. Maizlin ([email protected])

E175. The Role of Functional Imaging in Colorectal Cancer Objective: The goal was to evaluate the efficiency of MDCT in Garcia Figueiras, R.1; Goh, V.2; Gómez, A.1; Villalba Martín, C.1; identification of the mesorectal fascia (MRF) and the relationship Armesto, V.3; Baleato, S.4; Martínez Alegría, A.1; Padhani, A.2 1. of rectal carcinoma and lymph nodes to MRF within the MRF Complexo Hospitalario Universitario de Santiago de Compostela, envelope . Santiago De Compostela, Spain; 2. Paul Strickland Scanner Centre, Northwood, United Kingdom; 3. Complexo Hospitalario de Materials and Methods: Institutional approval was obtained for Lugo, Lugo, Spain; 4. Complejo Hospitalario de Pontevedra, this study . Ninety-two patients with a biopsy proven rectal carci- Pontevedra, Spain noma were evaluated with MDCT scan of the abdomen and pel- Address correspondence to R. Garcia Figueiras (roberto.garcia. vis and MRI of the pelvis . Rectal tumors were defined as tumors [email protected]) within 15 cm of the anal verge as measured with a rigid sig- moidoscope . Tumor downsizing following neoadjuvant therapy Background Information: Conventional imaging techniques in made the histopathology (the traditional gold standard) invalid . colorectal cancer (CRC) can depict morphologic features of the Hence, MRI was used as the only available reference standard for tumors but they cannot provide the full information to character- the evaluation of the accuracy of MDCT for the prediction of ize or monitor lesions . Functional imaging techniques such as dif- tumor invasion of the MRF . All examinations were reviewed inde- fusion-weighted (DW) MRI, perfusion techniques, PET-CT, or pendently by two dedicated abdominal radiologists who were MR-lymphography are increasingly being used to image CRC for blinded to each other, to the findings from another technique diagnosis, staging, and evaluating tumoral response and in post- and to clinical information . MRF at three levels, tumor position, treatment follow-up . More recently, these techniques may offer lymph nodes and relation of the tumor and lymph nodes to MRF the potential to establish a tumoral prognosis . were analyzed . Categorical agreement between MRI and MDCT and the interobserver agreement were determined by using Educational Goals/Teaching Points: The goals are to review Intraclass Correlation weighted kappa statistics . the indications and technical features for performing functional imaging in CRC; describe their relevant imaging findings; show Results: Strong correlation was found between MDCT and MRI the additional information gained by functional imaging in refer- in identification of MRF, tumor and lymph nodes size, location ence to conventional techniques in CRC, and understand what and relationship to MRF on the upper level . Moderate agreement the benefits are in combining different functional imaging tech- was identified on mid level and only fair correlation on the lower niques in CRC . level . These tendencies were present in both reviewers . Interobserver agreement was strong in all the evaluated parame- Key Anatomic/Physiologic Issues and Imaging Findings/ ters except visualization of mesorectal fascia on lower and mid Techniques: Perfusion imaging may be used to improve detec- levels . tion and characterization of CRCs, to monitor tumor response to therapeutic intervention, to improve delineation of residual or Conclusion: The results of this study differ from those previously recurrent tumor, to evaluate liver metastatic involvement, and to published demonstrating substantial agreement between the assess patient prognosis before and after treatment . DWI pro- readers in assessment of the tumor, MRF and lymph nodes on vides indirect information about tissue structure and intra/extra- MDCT . With exception of MRF assessment on lower rectal level cellular space and can be used to diagnosis CRCs, estimate and the distance of the nodes to MRF, other evaluated parame- tumor cellularity, and detect early changes following therapeutic ters were assessed with moderate and substantial agreement on intervention . Lymph node imaging is of great importance for the MDCT as compare to MRI . However, in such a high stake situa- staging of CRCs . Assessment of lymph nodes based on structural tion, excellent agreement should probably be required between imaging features alone is limited in sensitivity and specificity for the findings on MDCT compared with MRI in characterization of microscopic metastatic disease . Functional lymph node imaging tumor relationship to the MRF and MRF invasion in order to rec- can be performed using ultrasmall superparamagnetic iron oxide- ommend MDCT as MRI replacement for preoperative assessment based nanoparticles . Metabolic imaging, based on FDG-PET pro- of the circumferential resection margin in rectal cancer . vides complementary information to structural imaging tech- niques for diagnosis, staging, and treatment planning . Blood oxy- gen level-dependent (BOLD) functional MRI depicts tumor oxi- E177. Mechanisms of Spread of Rectal Tumors (CME Credit genation . Whole-body MRI, including DW sequences, may be Available) useful for staging CRC . Oliphant, M.; Ott, D. Wake Forest University, Winston-Salem, NC Address correspondence to M. Oliphant ([email protected]) Conclusion: Structural imaging alone can not provide all the information necessary for CRC management . Functional imaging Background Information: Recent advances in the combined techniques in CRC represent a noninvasive and quantitative trimodality therapy for rectal cancer, neoadjuvant radiation thera- opportunity to study tumoral physiology . py and chemotherapy along with surgery, has decreased the rate of local, regional, and distant recurrences . This treatment regi-

235 El e c t r o n i c Ex h i b i t s : Gastrointestinal men and more aggressive surgery (total mesorectal resection) Key Anatomic/Physiologic Issues and Imaging Findings/ has placed greater demands on the imaging of rectal tumors . Techniques: This presentation displays the anatomic location Pretreatment imaging for staging of disease is required to aid in and relationship of the duodenum with other organs such as management decisions . Essential for the interpreting of modern stomach, pancreas, gallbladder, liver, and other segments of the imaging is a knowledge of normal anatomy and an understand- gastrointestinal tract . Furthermore, it also demonstrates diverse ing of the pathways of spread of rectal cancer . disease entities of the duodenum classified as developmental, traumatic, inflammatory, neoplastic, and postsurgical conditions Educational Goals/Teaching Points: The anatomy of the rec- with conventional imaging modalities . tum, mesorectum, and pelvic organs is reviewed emphasizing the vasculature and lymphatic supply of the rectum and the relation- Conclusion: It is possible to understand the anatomy and ship of the rectum to its contiguous organs . The goal is the diverse disease category of the duodenum . Knowledge about the understanding of the anatomy as it relates to disease spread . duodenum can result in early and accurate diagnosis . The patterns of spread of rectal cancer are described to include local, lymphatic, and contiguous spread . Emphasis will be placed on the different patterns of spread from different regions E179. Esophageal Rupture: A Pictorial Review of Common of the rectum . The teaching point is the knowledge of the pat- and Unusual Causes (CME Credit Available) terns of spread aids in the radiologist’s search pattern . The exhib- Ferguson, E.1; Berkowitz, E.2; Goldman, S.1 1. The University of it correlates imaging findings with the staging of disease . The Texas Medical School at Houston, Houston, TX; 2. Emory teaching point is the correlation of imaging with staging and its University School of Medicine, Atlanta, GA affect on patient management . The integration of multiple imag- Address correspondence to E. Ferguson ([email protected]) ing modalities (MRI, MDCT, PET-CT) as they relate to evaluation of the patient in the staging of disease is discussed . The goal is Background Information: Esophageal perforation may occur in to learn the value and limitations of each technique . a variety of settings . Examples of different causes of esophageal perforation will be discussed and their classic radiological Key Anatomic/Physiologic Issues and Imaging Findings/ appearances on CT, plain film, and/or esophagram will be shown Techniques: The anatomy of the rectum, the mesorectum, and and explained . Sources of esophageal perforation to be demon- contiguous structures; the pathophysiology of the spread of rectal strated include Boerhaave’s syndrome from vomiting, iatrogenic cancer with emphasis on mesenteric, lymphatic, and contiguous causes such as Dobbhoff tube insertion and balloon dilatation, spread; MRI, MDCT, PET-CT imaging findings and how they relate acute rupture from trauma, malignant destruction, and an unusu- to staging of disease, and the impact of the imaging evaluation al variant of “esophageal” perforation involving a colonic interpo- on patient treatment will be discussed . sition, as well as an example of chronic perforation . Each type of perforation and its cause as well as imaging manifestations will Conclusion: Trimodality treatment and more aggressive surgery be discussed, diagnostic clues to aid in distinguishing among of rectal cancer have made it imperative that the radiologist them will be offered, and the natural outcome of each will be use modern imaging modalities to delineate the extent of dis- explained along with current treatment options . Moreover, radio- ease spread . In order to best achieve this goal search patterns logical findings in both acute and chronic perforations will based on anatomy and the knowledge of patterns of disease be demonstrated . spread is essential . The accurate assessment of pretreatment extent of disease greatly impacts patient management . Educational Goals/Teaching Points: Persons who view this exhibit will become familiar with the various entities that may cause esophageal perforation; recognize important imaging E178. The Duodenum: An Often Neglected Segment Despite abnormalities associated with esophageal perforation and diag- its Important Anatomic Location and Related Various nostic clues which aid in making that diagnosis, and will under- Disease Entities stand the pathophysiology of each type of perforation and why it Kim, Y.1; Jeong, W.1; Cho, O.2; Song, S.2; Koh, B.2; Cho, Y.1 1. occurs, the sequela of esophageal perforation and its treatment . Hanyang University Kuri Hospital, Kuri City, Kyunggido, South Korea; 2. Hanyang University Hospital, Seoul, South Korea Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to Y. Kim ([email protected]) Techniques: Each type of esophageal perforation will be dis- cussed and plain film, fluoroscopic, and/or computed tomo- Background Information: The duodenum is the shortest seg- graphic imaging of each will be shown . The pathophysiology and ment of the intestinal tract, so it is often overlooked by radiolo- radiographic findings of each type of perforation will be gists . However, it is located at both the intraperitoneal and retro- explained . peritoneal space and has a close relationship with various organs . As a result, the duodenum is involved in diverse primary Conclusion: This exhibit will review the many causes for esopha- and secondary disease processes . geal perforation . Showing examples of the radiological findings in esophageal perforation is useful since seeing how each type of Educational Goals/Teaching Points: The goals are to review its perforation manifests will aid in future diagnosis . This exhibit anatomic location and relationship among various adjacent includes common and rare as well as unusual causes for perfora- organs; review primary and secondary disease entities involving tion . Understanding these causes and recognizing patterns of the duodenum, and understand the importance of the duode- perforation is important because this affects patient care, out- num which radiologists and clinicians often neglect . come and prognosis . Acute and chronic manifestations and their sequela will be discussed .

236 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E180. Acute Esophageal Emergencies Encountered During E181. Gallbladder Cancer: Imaging Findings and Mechanism the “Ides of July”: One Hospital’s Experience from Late June of Spread (CME Credit Available) through Labor Day With the Arrival of the New House Staff Olsen, K.; Oliphant, M. Wake Forest University Baptist Medical Ferguson, E.; Goldman, S. The University of Texas Medical School Center, Winston Salem, NC at Houston, Houston, TX Address correspondence to K. Olsen ([email protected]) Address correspondence to E. Ferguson (ecferguson@hotmail. com) Background Information: Gallbladder carcinoma is the most common malignancy of the biliary tract . The prognosis is greatly Background Information: Most teaching-affiliated hospitals altered with detection of disease beyond local involvement . It experience a variety of changes during the month of July with spreads by several routes and the MDCT detection of metastatic the arrival of the new house staff . This manifests in a number of spread is crucial for initial staging and treatment planning . The ways, particularly with new residents and medical students who purpose of this exhibit is to review the pertinent anatomy of the may occasionally make inadvertent and unintentional errors gallbladder; highlight key imaging findings of gallbladder cancer, while in the process of learning to care for their patients . Many and discuss patterns of gallbladder cancer spread, with the inten- of these examples are captured radiologically . This exhibit focus- tion to enable the radiologist to develop a focused search pattern . es on acute iatrogenic esophageal emergencies encountered with the arrival of the new house staff in and around the month Educational Goals/Teaching Points: Educational goals of this of July . Examples include iatrogenic esophageal perforation from exhibit include developing a heightened awareness of the imag- tube placement and other interventions, perforation of a colonic ing appearances of gallbladder cancer and its mechanisms of interposition acting as an esophagus, and malpositioned spread; understanding the nuances of gallbladder anatomy and Dobbhoff feeding tubes placed into the airway, the lung, and the how they determine the direct, subperitoneal, and intraperito- pleural space . This pictorial review will serve to familiarize the neal routes of spread, and developing a search pattern in cases radiologist with possible iatrogenic esophageal trauma that may of gallbladder cancer . be encountered during this time and will be useful for the new house staff to caution them of potential errors that may occur so Key Anatomic/Physiologic Issues and Imaging Findings/ that they may be avoided in the future . Each type of esophageal Techniques: Gallbladder carcinoma spreads by several routes emergency, its imaging manifestations, and sequelae will be dis- determined by its anatomy . Direct spread occurs early to the liver cussed . especially segment four due to venous drainage . Other direct spread includes the duodenum and hepatic flexure due to ana- Educational Goals/Teaching Points: Radiologists should be tomic proximity and along the bile ductules . Subperitoneal acquainted with the various types of iatrogenic esophageal trau- spread occurs early via the lymphatics . The drainage is to the ma that may occur with the annual arrival of the new house staff cystic node and pericholedochal nodes then to the anterior and in July, at a time when new residents and medical students are posterior periportal nodes within the hepatoduodenal liga- learning to take care of their patients . They should be familiar ment, and to the celiac node and para-aortic nodes . Spread also with the appearance of malpositioned esophageal tubes, esopha- occurs within the hepatoduodenal ligament along the bile ducts . geal perforation, and other iatrogenic esophageal trauma and Hematogenous spread is usually a late occurrence . instruct new house staff about causes of potential iatrogenic Intraperitoneal spread is from the peritoneal surface of the gall- esophageal trauma and ways to avoid it . bladder . The gallbladder anatomy including gallbladder venous and lymphatic drainage, anatomic relations to the liver and Key Anatomic/Physiologic Issues and Imaging Findings/ other adjacent organs, and the patterns of cancer spread are dis- Techniques: This exhibit will focus on plain film, CT, and some cussed and illustrated . fluoroscopic findings associated with acute iatrogenic esophageal emergencies that are encountered with the arrival of the new Conclusion: The understanding of gallbladder anatomy and the house staff . patterns of gallbladder tumor spread are the keys for developing a logical and focused search pattern . Malignancy of the gallblad- Conclusion: A review of the radiographic manifestations of iatro- der has a poor prognosis . Localized tumor is generally associated genic esophageal emergencies that may occur with the arrival of with longer survival . The detection of spread to the liver and the new house during the “Ides of July” is helpful for the radiolo- regional lymph nodes greatly alters prognosis and influences gist, especially since esophageal trauma and malpositioned treatment planning . The radiologist plays an essential role in the tubes may at times be overlooked or can mimic other abnormali- detection of disease and the treatment of these patients . ties . It is also beneficial for the house staff to learn of some inadvertent errors to be avoided . When they occur, medical errors should be used as teaching tools, which is the goal of this exhib- E182. Meckel’s Diverticulum Revisited: Imaging it, and, more importantly, to spare future patients of some of Manifestations of its Many Faces (CME Credit Available) these mistakes . Shanbhogue, A1; Papadatos, D.1; Prasad, S.2; Ojili, V.2; Fasih, N1. 1. The Ottawa Hospital, Ottawa, Canada; 2. University of Texas Health Science Center-San Antonio, San Antonio, TX Address correspondence to A. Shanbhogue (shanbhogue_kp@ yahoo.com)

Background Information: Meckel’s diverticulum which results from improper closure of the omphalomesenteric duct is the most common congenital anomaly of the gastrointestinal tract,

237 El e c t r o n i c Ex h i b i t s : Gastrointestinal occurring in 2–3% of the population . It occurs with equal fre- Conclusion: Knowledge of the imaging features produced by dif- quency in both sexes and the majority of them are asymptomat- ferent etiologies of intussusception in adults is a key element for ic . Complications occur in approximately 4–40% of patients and accurate radiologic diagnosis, can aid in predicting the clinical include diverticulitis, hemorrhage from peptic ulceration, intus- course, and may help avoid unnecessary surgical explorations . susception, small intestinal obstruction, stone formation and neo- plasm . Diagnosis of Meckel diverticulum and these complications is difficult to establish in a substantial number of cases . The pur- E184. Imaging of Budd-Chiari Syndrome pose of this exhibit is to review the multimodality imaging of Kalra, N.; Virmani, V.; Singh, P.; Kang, M.; Anand, A.; Chawla, Y.; complicated and uncomplicated Meckel’s diverticulum . Khandelwal, N. Postgraduate Institute of Medical Education and Research, Chandigarh, India Educational Goals/Teaching Points: The goals are to present Address correspondence to N. Kalra ([email protected]) the radiological spectrum of various clinical presentations of Meckel’s diverticulum; identify the distinctive imaging features of Background Information: Budd-Chiari syndrome is a manifesta- each of these relatively uncommon entities, and describe imag- tion of hepatic venous outflow obstruction . It can be classified ing features that help differentiate them from various other caus- according to etiology as primary or secondary or according to the es that may mimic them . duration of disease as acute, subacute and chronic . The obstruc- tion can occur at any level from the hepatic venules to the Key Anatomic/Physiologic Issues and Imaging Findings/ cavoatrial junction . Prompt diagnosis of Budd-Chiari syndrome Techniques: In this exhibit, we will review the anatomy and and detection of the cause of obstruction, level of obstruction embryology of Meckel’s diverticulum . A comprehensive multimo- and stage of the disease is essential for appropriate management dality imaging review of various presentations and complications of the patient . like diverticulitis, hemorrhage, stone formation, intussusception and intestinal obstruction will also be presented . Certain salient Educational Goals/Teaching Points: 1 The. goals are for the features of these entities are described for reliable and accurate viewer of this exhibit to know the current status of various imag- diagnosis . ing modalities in the diagnosis of Budd-Chiari syndrome and understand the various imaging features helpful in diagnosing Conclusion: Meckel’s diverticulum can present with a wide and classifying Budd-Chiari syndrome . range of clinical and radiological manifestations ranging from being benign and indolent to acute and life threatening . Key Anatomic/Physiologic Issues and Imaging Findings/ Familiarity with these appearances allows an accurate diagnosis Techniques: Imaging modalities like Doppler sonography, MDCT, to initiate an accurate management . MRI, MR venography and conventional inferior vena cavagraphy are used for the diagnosis of Budd-Chiari syndrome . Each of these modalities has its advantages and pitfalls . Doppler sonog- E183. CT Findings of Adult Intussusception (CME Credit raphy, MDCT, MR venography and inferior vena cavagraphy are Available) useful for the evaluation of the hepatic veins and inferior vena Borghei, P.; Lockhart, M.; Morgan, D.; Clements, R. University of cava . On the other hand, dynamic CT and dynamic MRI provide Alabama Birmingham, Birmingham, AL information about the hepatic parenchymal changes and can be Address correspondence to P. Borghei ([email protected]) used for staging the disease .

Background Information: Unlike childhood intussusception that Conclusion: This didactic exhibit depicts the imaging features of is typically idiopathic, adult intussusception often has an identifi- Budd-Chiari syndrome and in a case format illustrates the various able cause . At times, diagnosis of this condition and identification stages and level of obstruction of Budd-Chiari syndrome . Primary of underlying pathology can be challenging, but the latter is as well as secondary Budd-Chiari syndrome cases will be dis- important for directing therapy . The purpose of this exhibit is to cussed . The advantages and disadvantages of various modalities demonstrate the variety of imaging features of intussusception including their current status will be highlighted . that may be produced by different underlying etiologies .

Educational Goals/Teaching Points: CT diagnostic criteria of E185. The Caudate Lobe Revisited: Cross-Sectional Imaging intussusception will be reviewed . Classification according to loca- Findings of Caudate Lobe Pathologies and Implications for tion (gastric, enteroenteric, ileocolic, ileocecal, or colocolic) and Surgery cause (benign, malignant, or idiopathic) will be demonstrated . Nagar, A.; Katabathina, V.; Prasad, S.; Ojili, V.; Choudhary, S.; Imaging features of transient intussusception without a lead Chintapalli, K. University of Texas Health Science Center at San point will be contrasted with those that have a lead point . Based Antonio, San Antonio, TX on these findings, the decision process for surgical vs . conserva- Address correspondence to A. Nagar ([email protected]) tive management will be discussed . Background Information: Accurate knowledge of the surgical Key Anatomic/Physiologic Issues and Imaging Findings/ anatomy of the caudate lobe is essential for planning liver trans- Techniques: CT is the most common imaging modality utilized plantation or hepatobiliary surgery . Surgical approach to segmen- to identify intussusception . Factors such as clinical demographics, tal or total resection of caudate lobe lesions depends on the size, size or length of the intussusception, and location are important type and precise location of the lesion as well as on the volume to the prognosis . In some cases, small bowel series, barium of the caudate lobe itself . Caudate hepatectomy is the most diffi- enema and pathology results will be correlated with CT findings cult and technically challenging procedure due to complex vascu- to better understand pathophysiology . lar supply and deep location . Caudate lobe accounts for 9% of

238 El e c t r o n i c Ex h i b i t s : Gastrointestinal the total mass of the liver and is used in transplantation . A spec- Key Anatomic/Physiologic Issues and Imaging Findings/ trum of lesions affects the caudate lobe either in isolation or as a Techniques: We will examine the following radiologic-pathologic part of multifocal process . A spectrum of pathologies, imaging correlations: 1 . Radiologic-pathologic correlation of the fat con- and surgical anatomy of the caudate with their surgical implica- taining non-neoplastic extrahepatic intra-abdominal conditions – tions will be discussed in this exhibit . mesenteric panniculitis, omental infarction, and mesenteric lipod- ystrophy; 2 . Radiologic-pathologic correlation of the fat contain- Educational Goals/Teaching Points: The goals are to discuss ing extrahepatic intra-abdominal neoplasms- lipoma, AML, clear embryology and applied anatomy of the caudate lobe with spe- cell RCC, PECOma, liposarcoma, adrenal adenoma, myelolipoma, cial emphasis on lobar changes in diffuse liver diseases, and teratoma and lipoleiomyoma .We will then present a differential review the spectrum of pathologies involving the caudate lobe diagnoses for various radiologic findings and discuss methods to with implications on liver surgery . distinguish various entities based on microscopic or macroscopic fat histopathologic presentations . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Caudate lobe, the first segment of the liver is func- Conclusion: A wide spectrum of fat containing neoplastic and tionally a part of the left lobe . The caudate lobe is characterized non-neoplastic diseases may occur in the abdomen . These disor- by separate vasculature and biliary ducts . The significance of cau- ders may either arise from the intra-abdominal organs or sur- date anatomy is reflected in major hepatic resections for various rounding mesenchyme . In this exhibit, we enumerate and review neoplastic and non-neoplastic conditions . Diffuse caudate lobe the fat containing extra hepatic neoplastic and non-neoplastic enlargement is the most common abnormality of the caudate diseases . Salient imaging findings of various conditions and lobe, which occurs commonly in cirrhosis and Budd chiari syn- methods to distinguish based on microscopic vs . macroscopic fat drome . The caudate lobe is also a target site for a wide spectrum and organ of origin are discussed . of focal pathologies including primary and secondary malignant neoplasms, benign tumors and infections . Malignant tumors of the caudate lobe manifest advanced disease and thus portend E187. Avoiding Pitfalls in Hepatocellular Carcinoma: MDCT poor prognosis . Microscopic involvement of the caudate lobe is Spectrum of Imaging Findings (CME Credit Available) commonly seen in hilar cholangiocarcinomas; resection of cau- Rowell, A.; Sangster, G.; Heldman, M.; Zibari, G.; Shokouh-Amiri, date is thus performed with right hepatectomy . Disorders in the H.; Roberts, K. Louisiana State University Health Science Center, porta hepatis may displace the papillary process of the caudate Shreveport, Shreveport, LA lobe and thus simulate an extrahepatic/retroperitoneal mass . Address correspondence to A. Rowell ([email protected]) Variations in the anatomy of the papillary process may give a pseudotumor like appearance . MDCT/MRI findings of focal/dif- Background Information: Hepatocellular carcinoma (HCC) is fuse abnormalities of the caudate lobe are presented with impli- increasing in incidence in the US as the number of patients with cations for surgery . hepatitis B and C infection rises . MDCT, along with ultrasound and MRI, plays an important role in the diagnosis and staging of Conclusion: In this exhibit, we discuss the relevant surgical anat- HCC . Because these tumors most often arise in liver parenchyma omy and spectrum of pathologies that involve the caudate lobe that is already altered by pathology, their identification and differ- and their implications on surgery . entiation from other lesions may represent a diagnostic chal- lenge . Hypervascular tumors and nontumoral vascular conditions may mimic HCC . MDCT is the modality of choice in differentiating E186. Fat Containing Extrahepatic Intra-Abdominal between these various entities . Neoplastic and Non-neoplastic Disorders: Cross-Sectional Imaging Findings with Pathological Correlation (CME Credit Educational Goals/Teaching Points: After reviewing this exhibit Available) the reader should be able to differentiate the HCC from other Chang, K.; Surabhi, V. University of Texas Houston Health Science benign and malignant hepatic conditions; recognize the MDCT Center, Pearland, TX imaging findings on typical and atypical HCC, and identify pitfalls Address correspondence to K. Chang ([email protected]) and false positive findings that may mimic HCC on MDCT .

Background Information: A wide spectrum of fat containing Key Anatomic/Physiologic Issues and Imaging Findings/ neoplastic and non-neoplastic diseases may occur in the abdo- Techniques: This presentation will discuss the MDCT imaging men . Our aim is to review the various fat containing extrahepatic findings of hepatocellular carcinoma and similar appearing neoplastic and non-neoplastic disorders and examine salient hepatic processes . imaging findings then confirm with histopathology . Conclusion: The aim of this presentation is to demonstrate the Educational Goals/Teaching Points: The goals are to review MDCT imaging findings that are typical for HCC as well as to the fat containing extrahepatic neoplastic and non-neoplastic dis- illustrate MDCT features that help distinguish HCC from other orders; discuss salient imaging findings of the broad spectrum of similar appearing conditions . fat containing extrahepatic intra-abdominal neoplastic and non- neoplastic pathologies; discuss the differential diagnosis based on radiologic findings, and correlate the above findings with gross histopathology .

239 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E188. Liver Involvement in Hereditary Hemorrhagic Educational Goals/Teaching Points: The goal is to differentiate Telangiectasia: A Multimodality Approach using CT, MR and radiologic findings of various fat-containing hepatic nodules with Color Doppler Sonography pathologic correlation . Kantawala, K.; Robinson, K.; Dahiya, N.; Middleton, W.; Menias, C.; Mallinckrodt Institute of Radiology, St. Louis, MO Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to K. Kantawala ([email protected]. Techniques: We reviewed many cases of fat containing hepatic edu) lesions (multifocal fatty infiltration, hepatic angiomyolipoma, nodular regenerative hyperplasia of the liver, hepatocellular ade- Background Information: Hereditary hemorrhagic telangiectasia noma, dysplastic nodules, and hepatocellular carcinoma with (HHT), also known as Rendu-Osler-Weber disease, is an autosom- fatty metamorphosis) and correlated between their radiologic al dominant vascular disease characterized by mucocutaneous or and pathologic findings . visceral angiodysplasias (telangiectases and arteriovenous malfor- mations) that may be distributed throughout the body . The report- Conclusion: Fat containing hepatic lesions were very diverse, ed prevalence is estimated to be around 1:100,000 to 200,000 . ranging from completely benign to malignant . By knowing the Liver, lungs and brain, in order of prevalence, are the most fre- additional features of fat containing hepatic nodules, we could quently involved visceral organs of the body . The aim of this exhib- make more precise diagnoses . it is to describe the multimodality imaging features of the hepatic manifestations of HHT using Ultrasound (US), CT and MR . E190. Higher Concentration Contrast Media for MDCT of the Educational Goals/Teaching Points: Familiarity with the hepat- Liver ic manifestations of HHT on multiple modalities results in more Lepanto, L. CHUM Hospital of St. Luc, Montreal, Canada accurate and early diagnosis and allows for better therapeutic Address correspondence to L. Lepanto ([email protected]) options if necessary . Objective: The goal was to evaluate whether the use of contrast Key Anatomic/Physiologic Issues and Imaging Findings/ media with a higher iodine concentration provide a benefit for Techniques: Our experience with a large group of HHT patients, rapid MDCT of the liver . with symptomatic and asymptomatic liver involvement, indicates that it is far more frequent than reported . It is characterized by Materials and Methods: A number of studies have demonstrat- intrahepatic vascular shunts, disseminated intraparenchymal tel- ed that the use of high concentration contrast media (HCCM; angiectases, and other vascular lesions . These lesions can cause 370-400 mgI/mL solution) provides improved enhancement dur- serious complications, including congestive cardiac failure, portal ing multiphasic MDCT of the liver and associated vasculature . hypertension, portosystemic encephalopathy, cholangitis, and However, in studies comparing various contrast media (CM) con- atypical cirrhosis . Thus, a correct diagnosis is important, and diag- centrations in which the injection rate and/or total grams of nostic imaging has a fundamental role in detecting vascular alter- iodine delivered varied between study groups, it has been diffi- ations in the liver . Grey-scale and Doppler sonography are nonin- cult to assess the benefit of HCCM . Two recently conducted stud- vasive, highly accurate and relatively low cost procedures for the ies compared a moderate concentration CM (320 mgI/mL) with screening of liver involvement in patients with hereditary hemor- a HCCM for first pass angiography and equilibrium phase MDCT rhagic telangiectasia . Multiphasic contrast-enhanced CT and MRI imaging of the liver . In both trials, all patients received equiiodine provide high quality multiplanar and angiographic reconstruc- (40 gI) doses of CM injected at 4 mL/second, improving the like- tions, allowing for detection and characterization of the com- lihood that any observed differences can be ascribed solely to plex anatomopathologic alterations typical of this disease . the CM concentration .

Conclusion: Diagnostic imaging based on ultrasound (US), CT Results: In the IMPACT trial [1], 121 patients undergoing liver and MRI has a fundamental role in evaluating hepatic involve- MDCT received iodixanol-320 (n=61) or iopamidol-370 (n=60) . ment in patients with HHT . Here, the HCCM iopamidol-370 also provided significantly higher HU values in abdominal aorta during the arterial phase of enhancement for both readers (reader 1: 301 3. vs . 273 .6 HU, E189. Fat-Containing Hepatic Nodules: Ultrasound, CT, MR p=0 02;. reader 2: 302 .0 vs . 275 1. HU, p=0 .03) . In this study, no and Pathologic Correlation significant difference was observed between the two CM during Cho, Y.; Kim, Y.; Jeong, W.; Cho, O.; Song, S. Hanyang University the portal-venous phase of enhancement . In the ACTIVE trial [2], Kuri Hospital, Kuri City, Kyunggido, South Korea 183 patients undergoing liver MDCT received iodixanol-320 Address correspondence to Y. Kim ([email protected]) (n=92) or iomeprol-400 (n=91) . In this study, iomeprol-400 pro- duced significantly greater enhancement of the aorta during the Background Information: Nowadays we can easily detect fat- arterial phase for both blinded readers (reader 1: 337 .3 vs . 294 .9 containing hepatic lesions by various image modalities . There are HU, p=0 .0004; reader 2: 325 .7 vs . 295 3. HU, p=0 01). and greater various histologic types of hepatic nodules that contain fat . Those enhancement of liver parenchyma during the portal-venous nodules have similar sonographic findings: hyperechoic nodules, phase (reader 1: 115 .1 vs . 108 .6 HU, p=0 04;. reader 2: 115 .2 vs . well circumscribed margin, and occasionally posterior attenua- 109 .3 HU, p=0 .05) . No significant difference was noted between tion . However, their CT and MR findings make it easy to diagnose the two study groups regarding enhancement of the inferior vena among them . These radiologic findings are well correlated with cava or portal vein . pathologic findings and we can differentiate these fat-containing hepatic nodules . Conclusion: In well-designed comparative trials, the use of CM with higher iodine concentration (370-400 mgI/mL) results in greater enhancement for vascular phase imaging . The finding that 240 El e c t r o n i c Ex h i b i t s : Gastrointestinal parenchymal phase imaging may also be improved with the use E192. MR Cholangiopancreatography of Liver Transplant of HCCM deserves further clinical evaluation . The use of HCCM Biliary Complications With Radiographic Cholangiographic provides the ability to reduce CM volumes, potentially minimizing Correlation (CME Credit Available) patient exposure to CM while reducing examination costs . Alsheik, N.; Taylor, A.; Sadowski, E.; Paul, R.; Pfau, P.; Reeder, S. 1 . Sahani DV, et al . Invest Radiol . 2007; 42:856-861 . University of Wisconsin Hospitals and Clinics, Madison, WI 2 . Romano L, et al . Br J Radiol. 2008; In Press . Address correspondence to N. Alsheik ([email protected])

Background Information: Post liver transplant biliary complica- E191. Portal Vein Thrombosis: A Multimodality Approach to tions occur commonly (19-30%) and are usually evaluated with the Diagnosis of Bland vs. Malignant Thrombi (CME Credit ultrasound, liver biopsy and/or direct (endo- Available) scopic retrograde cholangiopancreatography [ERCP] or percuta- Masuda, E.; Myers, D. Henry Ford Hospital, Detroit, MI neous cholangiography [PTC]] . Direct cholangiography is consid- Address correspondence to E. Masuda ([email protected]) ered the diagnostic gold standard for post-transplant complica- tions and can provide treatment at the time of diagnosis . Background Information: Portal vein thrombus is a frequently However, direct cholangiography is invasive and confers a risk of encountered finding in hepatic imaging . Bland thrombosis of the pancreatitis, ascending cholangitis and duodenal perforation . portal vein can occur secondary to numerous benign etiologies Although these complications are infrequent, they are devastating such as infection, surgical intervention, nonspecific parenchymal in the immune-compromised transplant patient . MR cholangio- disease, and secondary to malignancy; particularly hepatocellular pancreatography (MRCP) offers a viable, noninvasive means to carcinoma (HCC) . Portal vein thrombosis has been shown to directly visualize postoperative biliary strictures and bile ducts occur in up to 30% of cases of HCC, and in up to 5% of patients above the stricture, which ERCP does not demonstrate . MRCP with cirrhosis or portal hypertension . Malignant tumor thrombus, offers the benefit of diagnosing postoperative biliary complica- however, is much less common, and usually is discovered inci- tions (anastomotic stricture, intrahepatic nonanastomotic stricture dentally during cancer staging . Malignant tumor thrombosis of and extrahepatic nonanastomotic stricture) as well as extrabiliary the portal vein occurs most commonly secondary to HCC . It is complications (recurrence of preoperative hepatitis, biloma, vas- therefore of value to differentiate bland vs . malignant thrombus, cular compromise) . as this plays a crucial role in the correct staging and appropriate treatment for these patients, as well as avoiding unnecessary Educational Goals/Teaching Points: The aim of this exhibit is risks involved in anticoagulation therapy if a malignant thrombus to review the physics of our current MRCP protocol, which has is misdiagnosed . This exhibit will discuss the imaging characteris- enhanced background suppression secondary to the addition of tics of various modalities used to differentiate bland vs . malig- a T2-prep pulse sequence module, and demonstrate the utility of nant thrombus, including findings on CT, ultrasound, PET-CT, and MRCP as a viable, noninvasive alternate means of direct visualiza- MRI . This exhibit will also discuss the potential pitfalls in the tion of the biliary tree in post liver transplant patients . diagnosis of bland vs . malignant portal vein thrombosis with these various imaging modalities . A short series of challenge Key Anatomic/Physiologic Issues and Imaging Findings/ cases will be presented at the end of our exhibit . Techniques: Our current MRCP imaging protocol will be reviewed . The diagnostic efficacy of MRCP for postoperative bil- Educational Goals/Teaching Points: The exhibit will differenti- iary and extrabiliary complications is compared to direct cholangi- ate imaging characteristics on CT, ultrasound, PET-CT and MR, ography (ERCP, PTC) . Delayed images with gadobenate dimeglu- which can be used by the radiologist to confidently distinguish mine determine which strictures are physiologically significant . between bland vs . malignant portal vein thrombus (PVT); Complications following orthotopic liver transplantation describe the sensitivity and specificity of malignant portal vein include anastomotic and nonanastomotic strictures, bile leak, and thrombus detection by various modalities as described by the biliary recurrence of pre-existing preoperative conditions . current literature, and identify artifacts that can falsely present as portal vein thrombus . Conclusion: MRCP detects and characterizes biliary strictures as accurately as direct cholangiography (ERCP, PTC) and serves as an Key Anatomic/Physiologic Issues and Imaging Findings/ indispensable roadmap for interventional procedures . Also, MRCP Techniques: CT characteristics of malignant portal vein thrombus images the biliary tree in patients in whom direct cholangiography include: intrathrombus neovascularity, venous expansion, and is unsuccessful . A negative MRCP examination may obviate the direct invasion of the portal vein . Generalized enhancement on need for diagnostic ERCP or PTC in patients with elevated liver CT strongly suggests malignant PVT . Hypermetabolism on PET-CT enzymes following liver transplantation, limiting direct cholangiog- may suggest either malignant tumor or septic thrombophlebitis . raphy to patients who require therapeutic intervention alone . The exhibit will discuss the identification of neovascularity and Doppler flow characteristics of malignant thrombus on ultra- sound . E193. MR Cholangiography for Evaluation of Orthotopic Liver Transplant Complications: A Viable Noninvasive Conclusion: Portal vein thrombus is a common finding in hepat- Alternative to Radiographic Direct Cholangiography ic imaging . The distinction of bland vs . malignant thrombus by Alsheik, N.; Taylor, A.; Sadowski, E.; Paul, R.; Pfau, P.; Reeder, S. the radiologist through the imaging characteristics discussed in University of Wisconsin Hospitals and Clinics, Madison, WI this exhibit plays a crucial role in correct staging and therapy . Address correspondence to N. Alsheik ([email protected])

Objective: Although direct cholangiography (endoscopic retro- grade cholangiopancreatography [ERCP] and percutaneous cholangiography [PTC]) is the diagnostic gold standard of 241 El e c t r o n i c Ex h i b i t s : Gastrointestinal postorthotopic liver transplant complications, it confers a multitude Key Anatomic/Physiologic Issues and Imaging Findings/ of risks in immunocompromised patients . Post-transplantation Techniques: Normal liver parenchyma has similar signal intensity biliary complications occur between 19-30% . MR cholangiopan- on gradient echo in-phase and opposed-phase images . Hepatic creatography (MRCP) offers a viable, noninvasive means of direct steatosis can be detected if there is signal intensity loss on visualization of the biliary tree, vasculature and liver . Our current opposed-phase images and the severity of steatosis can be grad- MRCP protocol has enhanced background suppression secondary ed by the degree of signal loss . Fat deposition can also be diag- to a T2-prep pulse sequence module . Delayed images with gado- nosed with the application of other fat suppression techniques, benate dimeglumine offer crucial physiologic information regard- but this is less sensitive than chemical shift imaging . The signal ing the significance of biliary strictures . The purpose of this study changes caused by focal steatosis can give rise to pseudolesions is to establish the efficacy of MRCP compared to direct cholangi- in the liver, and the presence of steatosis can also complicate the ography in liver transplant patients . characterization of focal liver lesions . We will present recent examples to illustrate the varied appearances . Materials and Methods: Fourteen liver transplant patients were referred for both MRCP and direct cholangiography . These stud- Conclusion: MRI is sensitive and specific for detection of fat in ies were independently interpreted by two radiologists . At MRCP, the liver, but hepatic steatosis has many manifestations and the strictures were graded as mild, moderate, or severe based on radiologist must be aware of these varied appearances to avoid radiographic size of stricture and physiology of delayed gado- misdiagnosis . benate dimeglumine excretion . At ERCP, strictures were graded as mild, moderate or severe based on fluoroscopic size of stric- ture and resistance with balloon sweep of the stricture . Also E195. Liver Imaging at 3T: Technical Optimization recorded were the presence of upstream and downstream dilata- Mwangi, I.; Shiehmorteza, M.; Sirlin, C. University of California- tion, intrahepatic or extrahepatic strictures, bile leak/biloma, and San Diego, San Diego, CA transplant vascular complications . Address correspondence to I. Mwangi ([email protected])

Results: MRCP had a sensitivity and specificity of 100% in the Background Information: MR imaging at 3T provides higher detection of six anastomotic strictures and three cases of multifo- signal to noise ratio and higher sensitivity to contrast agents than cal intrahepatic strictures . MRCP was particularly useful in dem- at 1 5T. . In principle, this makes 3T MR imaging suited for detec- onstrating the biliary tree in patients in whom direct cholangiog- tion of small cancers and difficult lesions, both in cirrhotic and raphy was unsuccessful . Six patients received delayed imaging . In noncirrhotic livers . However, consistently high image quality may each case with delayed imaging, the grading of strictures as mild, be difficult to achieve at 3T . This exhibit demonstrates how opti- moderate or severe correlated with ERCP grading of strictures . mization of liver imaging at 3T can be achieved, by selection of appropriate sequences and adjustment of technical parameters . Conclusion: MRCP detects and characterizes biliary strictures as Basic physics and technical concepts, schematic diagrams, and accurately as direct cholangiography and serves as an indispensa- clinical illustrations are presented . ble roadmap for interventional procedures . A negative MRCP examination may obviate the need for diagnostic ERCP or PTC in Educational Goals/Teaching Points: The learning objectives are patients with elevated liver enzymes following liver transplanta- to review basic concepts of MR imaging of the liver at 1 .5T and tion, limiting invasive cholangiography to patients requiring thera- 3T; understand theoretical and practical advantages and disadvan- peutic intervention alone . tages of liver imaging at 3T, and learn how to optimize 3T exami- nations of the liver .

E194. The Varied MRI Appearances of Diffuse and Focal Key Anatomic/Physiologic Issues and Imaging Findings/ Hepatic Steatosis Techniques: High field strength MRI (3T) accentuates motion, Yang, N.1; Goodwin, M.2; Chang, S.1; Schelleman, A.2; Elser, S.1 standing wave, susceptibility and chemical shift artifacts . Also, 1. Vancouver General Hospital, Vancouver, Canada; 2. Austin obtaining in- and out-of-phase sequences with appropriate echo Health, Heidelberg, Victoria, Australia spacing to characterize lipid accumulation may be challenging . Address correspondence to N. Yang ([email protected]) Conclusion: By applying basic technical concepts it is possible to Background Information: As the rates of obesity, diabetes and formulate robust and reliable 3T sequences that generate con- alcohol use increase in the community, so too does the inci- sistently high image quality, avoid artifacts, and delineate liver dence of diffuse and focal hepatic steatosis . In addition, nonalco- lesions with high conspicuity . holic steatohepatitis (NASH) is now known to be a major cause of cirrhosis . The varied appearances of fat in the liver can lead to diagnostic confusion, in turn leading to unnecessary invasive pro- E196. Liver Lesion Characterization: “The Good, the Bad and cedures . MRI is highly sensitive and specific for intrahepatic fat, the Ugly” (CME Credit Available) and we aim to review its varied appearances . Shanbhogue, A.1; Cao, L.2; Papadatos, D.1 1. The Ottawa Hospital, Ottawa, Canada; 2. No Institutional Affiliation Educational Goals/Teaching Points: The goals are to review Address correspondence to A. Shanbhogue (shanbhogue_kp@ the risk factors, pathophysiology, epidemiology and MR imaging yahoo.com) appearances of diffuse and focal hepatic steatosis . In addition, the MRI physics will be reviewed . Background Information: Characterization of liver lesions is one of the commonest indication for which an outpatient MRI is indicated . The differential diagnosis of liver nodules is wide and depends on presence or absence of underlying liver parenchymal 242 El e c t r o n i c Ex h i b i t s : Gastrointestinal disease, age and sex of the patient and a number of other risk internal fat . Cystic bile duct hamartomas have been mistaken for factors . The diagnosis is effortless when classical imaging mani- malignancy . When treatment is required, these masses respond festations are present, but may be more challenging and difficult favorably to simple deroofing procedures, thereby avoiding hepa- when the imaging manifestations are not classic . The purpose of tectomy . Hepatocellular carcinoma and cholangiocarcinoma this exhibit is to review the imaging spectrum of a diverse group appear differently on pre- and postcontrast sequences . Properly of benign and malignant liver nodules which demonstrate atypi- timed arterial phase imaging and subsequent multiphasic imag- cal imaging characteristics . ing are vital in this discrimination . Metastases have a different pattern of enhancement after gadolinium than primary hepato- Educational Goals/Teaching Points: The goals are to discuss cellular carcinoma . imaging features of liver lesions on ultrasound, CT and MRI with emphasis on making a specific diagnosis, and to discuss potential Conclusion: By implementing a comprehensive yet rapid MRI pitfalls using a standard algorithmic approach . protocol for abdominal imaging and employing an algorithmic approach, the radiologist can confidently tackle hepatic masses . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: In this exhibit, we will review the classic algorithmic approaches to various liver nodules in cirrhotic and noncirrhotic E198. Delayed Enhancing Hepatic Lesions on MR Imaging livers and highlight the pitfalls of using a classic algorithmic (CME Credit Available) approach . We will also present numerous simple and Morani, A.; Elsayes, K.; Liu, P.; Hussain, H.; Weadock, W.; Caoili, E. benign (“The Good”), difficult (“The Bad”) and very complex University of Michigan, Ann Arbor, MI (“The Ugly”) liver nodules using ultrasound (US), CT and MRI . Address correspondence to A. Morani ([email protected])

Conclusion: Liver nodules can vary from benign to malignant Background Information: Many pathologic entities in the liver causes . Imaging features can be nonspecific . We plan on expos- enhance on delayed postgadolinium imaging . This enhancement ing the audience to a classic algorithmic approach, with review of pattern may be due to fibrous tissue, edema or vascular spaces imaging findings on US, CT and significant emphasis on MRI, in within these entities . an attempt to properly characterize liver nodules . We will expose the audience to classic and nonclassic appearances of both Educational Goals/Teaching Points: The goals are to illustrate benign and malignant liver nodules . Finally, we will present more the spectrum of delayed enhancing hepatic lesions on MRI, and challenging cases to interpret . to describe their temporal enhancement characteristics and sig- nal intensities on current comprehensive pulse sequences .

E197. Hepatic Masses: An Algorithmic Approach (CME Credit Key Anatomic/Physiologic Issues and Imaging Findings/ Available) Techniques: Benign entities such as intrahepatic fibrosis, postra- Krishnamoorthy, S.; Sebastian, S.; Salman, K.; Rostad, B.; Li, J.; diotherapy changes, , pseudotumor, abscesses Sharma, P.; Kalb, B.; Spivey, J.; Sarmiento, J.; Martin, D. Emory and hemangiomas, and malignant entities such as hemangioen- University, Atlanta, GA dotheliomas, cholangiocarcinomas, combined hepatocellular car- Address correspondence to S. Krishnamoorthy (saravanan. cinoma-cholangiocarcinoma, and hypovascular metastases show [email protected]) characteristic delayed enhancement . These lesions have variable morphologic features, signal intensities and early enhancement Background Information: The superlative soft tissue contrast pattern . MR imaging can help distinguish between these entities . and depiction of hepatic vasculature, makes MRI ideal for charac- terization of hepatic masses . Modern MRI sequences allow for Conclusion: Delayed enhancing hepatic lesions can be diag- faster scanning and greater resistance to motion artifacts . In order nosed and differentiated on MRI by assessing their temporal to thoroughly exploit the advantages of MRI, proper unenhanced enhancement and signal characteristics . and postgadolinium sequences are mandatory . Once such a sys- tem is established, the radiologist must understand the imaging features of masses to determine the optimal course of action . E199. Diffusion-Weighted MRI Findings of Diffuse Liver Disease in Patients with Orthotopic Liver Transplant Educational Goals/Teaching Points: The goals are to define a Momtahen, A.; Balci, N.; Fattahi, R.; Wolverson, M. Saint Louis protocol for hepatic imaging by MRI; differentiate common University, Saint Louis, MO benign hepatic masses, including cyst, cystic bile duct hamarto- Address correspondence to A. Momtahen ([email protected]) ma, hemangioma, focal nodular hyperplasia, and hepatic adeno- ma; identify MRI features of hepatic metastases and primary Objective: The goal was to evaluate the role of diffusion-weight- hepatic malignancies; outline a followup protocol for dysplastic ed MRI (DWI) in the assessment of diffuse liver parenchymal dis- nodules and hepatocellular carcinoma, and describe the imaging ease in patients with orthotopic liver transplants (OLT) . criteria for hepatic transplantation as a treatment for hepatocellu- lar carcinoma . Materials and Methods: DWI of 31 OLT patients (20 men and 11 women; mean age 53 years) and 20 patients without liver dis- Key Anatomic/Physiologic Issues and Imaging Findings/ eases (11 men and nine women; mean age 49 years) were retro- Techniques: Hemangiomas demonstrate increased T2 signal . spectively evaluated . All liver transplant patients had histopatho- They have nodular peripheral enhancement on the arterial phase logically proven diffuse liver disease . Patients with pathologic with subsequent progressive enhancement with time . Hepatic diagnosis of transplant rejection were excluded from the study . adenoma features arterial enhancement and frequently contains DWI was acquired on a 1 .5T MR scanner with b=0, 300, and 600

243 El e c t r o n i c Ex h i b i t s : Gastrointestinal seconds/mm2 . Apparent diffusion coefficient (ADC) maps were as a surrogate for liver lesion enhancement the LHA, SVHAD and created on all patients and ADC values of the liver were displayed HAD all had greater enhancement than earlier phases . These on a color map . Quantitative measurement of ADC values was landmarks may be useful to predict adequacy of timing for early performed for each segment of the liver separately . Effects of dynamic liver imaging . Assessment of the subtype of early fibrosis, cholestasis, and necroinflammatory activity grade accord- enhancement may allow better judgment of liver lesions ing to the Scheuer classification on the mean ADC value of the enhancement and characterization, which may prove valuable liver were evaluated using linear regression analysis . when assessing the response of liver lesions to treatment inter- ventions . Results: Three patients had hepatitis, two patients had cholesta- sis and hepatitis, two patients had cholestasis and fibrosis, 14 patients had hepatitis and fibrosis, and ten patients revealed E201. Ferumoxides Shift to the Spleen During MR Imaging cholestasis, hepatitis, and fibrosis . The grade of necroinflammato- of the Cirrhotic Liver ry changes and cholestasis did not have any effects on the ADC Mwangi, I.; Shiehmorteza, M.; Mantrawadi, L.; Sirlin, C. University values . ADC values were lower than the control group when of California-San Diego, San Diego, CA fibrosis was present . In the patient group, the mean ADC value of Address correspondence to I. Mwangi ([email protected]) the liver was 1 .72 mm2/second in the absence of fibrosis and 1 .21 mm2/second in grade 4 fibrosis . Mean ADC value of the Objective: The objective was to retrospectively identify and liver in the control group was 1 .77 mm2/second . ADC color describe imaging features of ferumoxides shift to spleen in cir- maps in patients with diffuse liver changes revealed distinctly dif- rhotic patients undergoing MR imaging . ferent patterns as compared to the control group . Materials and Methods: In this IRB-approved, HIPAA-compliant, Conclusion: DWI with color ADC map can reveal the presence of descriptive study, patients with ferumoxides shift to spleen were liver fibrosis in patients with OLT . identified retrospectively by searching the abdominal imaging teaching file of an academic hospital . Ferumoxides shift was defined as reduced signal of the spleen relative to liver on T2*- E200. Early Contrast Enhancement of the Liver: Exact weighted gradient-recalled-echo images . Two radiologists in con- Description of Phases Using MRI sensus evaluated the images . Patients’ medical records were Neto, J.1; Ramachandran, S.2; Semelka, R.2; Troy, J.2 1. No reviewed . Institutional Affiliation; 2. University of North Carolina Hospital, Chapel Hill, NC Results: Ten patients (five women, five men; mean age, 50 Address correspondence to S. Ramachandran (sudha_ramachan- years; range, 39-63 years) with cirrhosis (hepatitis C (n=4), alco- [email protected]) hol (n=4), nonalcoholic steatohepatitis (n=1), unknown (n=1)) and ferumoxides shift to spleen were identified . All had abnor- Objective: The purpose was to classify early postcontrast mal liver function tests . Two underwent liver transplantation after enhancement of the liver into subtypes, using vessel enhance- imaging (three and 12 months respectively) . All had splenomega- ment patterns; and correlate these findings with quantitative ly, two with Gamna Gandi bodies . In three, liver parenchyma abdominal organ enhancement . cloaking hepatic vessels was hypointense to background liver, suggesting preferential perivascular uptake of ferumoxides . Materials and Methods: All abdominal MRI studies performed between June 1, 2007 and June 18, 2007 were retrospectively Conclusion: This is the first study to our knowledge to describe reviewed . The final study population comprised 114 studies . MR ferumoxides shift to spleen as an entity in cirrhotic patients, studies were performed by using a set delay of 18 seconds undergoing MR imaging . Further studies are needed to establish between the initiation of contrast injection and image acquisi- the prevalence and clinical significance of this finding . tion . Subjective determination of phases of enhancement was made by evaluating the presence of contrast in various abdomi- nal vascular structures and the perceived extent of organ E202. The Varied Imaging Appearances of Fat Containing enhancement . Correlation was made between the subjective Lesions of the Liver: A Pictorial Review to Aid Differential assessment and quantitative percentage enhancement of pancre- Diagnosis (CME Credit Available) atic, liver, spleen and kidney parenchyma . Yang, N.; Zwirewich, C.; Chang, S. Vancouver General Hospital, Vancouver, Canada Results: Five patterns of early postcontrast enhancement were Address correspondence to N. Yang ([email protected]) determined subjectively which included: early hepatic arterial (EHA) [14 studies], mid hepatic arterial (MHA) [23 studies], late Background Information: Fat may be present in a variety of hepatic arterial (LHA) [33 studies], splenic vein only hepatic arte- benign and malignant liver lesions . The detection of fat within a rial dominant (SVHAD) [20 studies], and hepatic arterial domi- liver lesion can be critical in the characterization of the lesion, nant (HAD) [24 studies] . Percentage pancreatic enhancement and coupled with the other imaging characteristics, can be help- was over 70% for LHA, SVHAD, and HAD, which was significantly ful in narrowing the differential diagnosis . Ultrasound (US), CT, different than for the EHA and MHA phases (p<0 .001) . and MRI can be used to detect intralesional fat . In particular, Percentage liver enhancement was 33 .4% in the HAD, which was MRI is both sensitive and specific for demonstrating both macro- significantly greater than at any of the earlier phases, (p<0 001). . scopic fat and/or intracellular lipid within a liver lesion .

Conclusion: Vascular landmarks can be used to classify the spe- Educational Goals/Teaching Points: The goals are to describe cific early phases of enhancement . Using pancreatic parenchyma both benign and malignant types of fat containing liver lesions

244 El e c t r o n i c Ex h i b i t s : Gastrointestinal and to describe and demonstrate the imaging appearances of ground of high hepatic parenchymal signal . Additionally, the bil- various fat containing liver lesions across a range of modalities, iary excretion of the agent is best seen between 20-40 minutes including US, CT and MRI, to aid in narrowing the differential postinjection and can be used to assess the patency and caliber diagnosis . of the intrahepatic and extrahepatic biliary ductal system .

Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: Hepatobiliary specific contrast agents are important Techniques: Although the presence of fat can be documented for a variety of reasons . These could allow for improved diagnos- on US and CT, MRI is the most specific imaging technique for tic accuracy in liver lesion detection and characterization over demonstrating both an admixture of fat and soft tissue within a existing extracellular contrast media . In addition, this has the lesion as well as pure macroscopic fat . A variety of MR tech- potential to be used for functional imaging of the hepatobiliary niques can be used to detect intralesional fat, but most com- system, including evaluation for acute cholecystitis . The biliary monly chemical shift opposed phase gradient echo sequences excretion helps evaluate the cystic duct patency, providing similar and fat saturation sequences are used . Intracellular lipid-contain- functional information as a nuclear medicine cholescintigraphic ing lesions include focal hepatic steatosis, hepatic adenoma, scan, while still providing the anatomic detail of a conventional focal nodular hyperplasia, regenerative nodules and hepatocellu- MR study . lar carcinoma . Macroscopic fat-containing liver lesions include hepatic adenoma, hepatocellular carcinoma, angiomyolipoma, lipoma, hydatid cyst, metastases and pericaval fat . E204. Quantitative Hepatic Imaging: Current and Emerging Trends Conclusion: The recognition of fat within a focal liver lesion is an Bajpai, S.; Singh, A.; Kambadakone R. A.; Catalano, O.; Blake, M.; important finding, as this coupled with other imaging characteris- Sahani, D. Massachusetts General Hospital, Boston, MA tics, aids in narrowing the differential diagnosis of these liver Address correspondence to S. Bajpai ([email protected]) lesions . US, CT and MRI can be used to further characterize these lesions, but in particular, MRI is the most specific tool for demon- Background Information: With the evolution of medicine cou- strating both macroscopic and microscopic fat deposition within pled with imaging advances, expectations from radiology have lesions . increased substantially . The liver is a target organ for several focal and diffuse disease processes . Quantification in liver has many important clinical applications ranging from the estimation of E203. MRI of the Hepatobiliary System with a Liver-Specific total hepatic fat, iron, preoperative evaluation of normal liver vol- Contrast Agent umes in hepatic transplantation and increasingly in functional Gupta, R.; Brady, C.; Massey, C.; Merkle, E. Duke University evaluation such as perfusion imaging . The purpose of this exhibit Medical Center, Durham, NC is to study the current role of imaging in the quantification of Address correspondence to R. Gupta ([email protected]) normal liver, diffuse hepatic diseases and focal liver lesions and its impact on patient management, and to discuss the emerging Background Information: Recently, hepatobiliary specific agents trends in volumetric evaluation of the liver by imaging . have become commercially available . One such agent is gadoxe- tate disodium . It is unique in that it has a dual route of excretion Educational Goals/Teaching Points: The exhibit will discuss with approximately 50% hepatic excretion and 50% renal excre- imaging methods and techniques in the quantification of liver fat tion . Most MRI contrast agents currently in use are extracellular and iron; highlight the role of CT and MR in liver volumetric esti- agents and have negligible amounts of excretion through the mation prior to hepatic transplantation; describe the clinical hepatobiliary system, primarily being excreted by the kidneys . applications and role of imaging in tumor volumetry, and discuss Hepatocyte-specific agents can be used in a wide range of hepa- imaging techniques such as perfusion CT, MR, PET for the quanti- tobiliary applications and the purpose of this exhibit is to show tative evaluation of functional aspects of liver . cases in which the unique properties of liver-specific contrast agents can be utilized effectively . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The exhibit will outline the performance of current Educational Goals/Teaching Points: The goals of this exhibit and novel techniques such as ultrasound, CT, MRI and MR spec- are to familiarize the reader with MR imaging protocols and troscopy in hepatic fat quantification; technique and protocols of sequences utilized with liver-specific contrast agents and how imaging techniques such as MR in hepatic iron quantification; they differ from protocols used with extracellular contrast agents; volumetric assessment of functional and anatomical liver volume illustrate the impact that the liver-specific contrast has on in hepatic donors for presurgical evaluation; tumor volumetry T2-weighted imaging; help understand how the hepatocyte-spe- and its impact on planning surgery and treatment strategies such cific nature of these agents can help with liver lesion detection as for proton beam therapy and selective internal radiation thera- and characterization, illustrate specific imaging features of liver py (SIRT), and discuss perfusion imaging of the liver by CT and lesions with these agents, and learn how the biliary excretion of MRI for quantification of hepatic microvascular physiology and such agents can be used to evaluate for biliary ductal system angiogenesis . pathology on delayed images . Conclusion: This exhibit highlights established hepatic quanti- Key Anatomic/Physiologic Issues and Imaging Findings/ tative imaging techniques and their pitfalls as well as novel Techniques: Using a hepatocyte-specific agent, the liver reaches methods also capable of providing useful liver quantification maximal enhancement approximately 15-30 minutes postinjec- information . tion . This allows for lesions such as hepatocellular carcinoma, adenomas, and cysts to be more conspicuous against the back-

245 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E205. Postoperative Diagnostic Workup of Orthotopic Liver Results: The associated diseases with perihepatitis were vari- Transplantation: Impact of Recent Advances of Cross- ous; Fitz-Hugh-Curtis (FHC) syndrome (n=13), gastrointestinal Sectional Imaging (CME Credit Available) inflammation or perforation (n=10), hepatobiliary problem Kanaan, Y.; Elsayes, K.; Trout, A.; Hussain, H.; Bude, R.; Dasika, N.; (n=6), trauma (n=6), carcinomatosis peritonei (n=1), dialysis-re- Francis, I. University of Michigan, Ann Arbor, MI lated peritonitis (n=1), and pyelonephritis (n=1) . In cases of Address correspondence to Y. Kanaan ([email protected]) FHC syndrome and cholangitis, subcapsular parenchymal enhancement was also noted . In cases of FHC syndromes, right Background Information: Orthotopic liver transplant (OLT) is a upper quadrant (RUQ) pain was the main complaint, however in common procedure and its complications should be identified other associated diseases, pain in the primary inflammatory foci quickly to avoid problematic outcomes . Familiarity with multimo- was the main complaint . dality imaging findings is extremely important for the radiologist and consulting surgeon . In this presentation we will review the Conclusion: Perihepatitis is a relatively nonspecific finding not surgical procedures and anatomic sequelae of liver transplanta- only seen in FHC syndrome but also seen in other inflammatory tion; discuss the current diagnostic workup and utility of various processes . RUQ pain is less commonly associated in patients cross-sectional modalities and interventional radiology in reveal- with perihepatitis other than FHC syndrome . ing the complications of liver transplantation, and describe what the surgeon needs to know when complications occur . E207. The Radiological Spectrum of Peritoneal Educational Goals/Teaching Points: The exhibit provides a dia- Carcinomatosis (CME Credit Available) grammatic demonstration of OLT surgery, with imaging correla- Vummidi, D.; Kolokythas, O.; Bush, W.; Lee, J.; Dighe, M. University tion; outlines the complications of OLT including pathophysiology of Washington School of Medicine, Seattle, WA and incidence; discusses imaging strategies post OLT, including Address correspondence to D. Vummidi ([email protected]) diagnostic workup and utility of various imaging techniques in the postoperative evaluation of orthotopic liver transplantation, Background Information: The peritoneum is a complex serous and reviews the imaging features of OLT complications and what membrane with a visceral component that envelopes the organs the surgeon needs to know when complications occur . and a parietal component lining the abdominal wall . The perito- neal cavity is a potential space between these two layers that can Key Anatomic/Physiologic Issues and Imaging Findings/ be affected by various pathological processes including neopla- Techniques: A retrospective analysis of orthotopic liver trans- sia . Secondary or metastatic involvement is more commonly plants performed at the University of Michigan Health Systems encountered with ovarian cancer being the prototypical causative was reviewed and the sensitivities and specificities of the radio- lesion . logic work-up was determined . Examinations that were evaluated included: ultrasound, CT, MRI, interventional radiology and nucle- Educational Goals/Teaching Points: The goals are to illustrate ar medicine . The surgical and pathologic findings were used as the anatomy of the peritoneum and describe its various compart- the standard for imaging accuracy . ments; describe the various pathways of spread of malignant tumor; depict the multimodality approach to imaging peritoneal Conclusion: There is a wide spectrum of complications following carcinomatosis, and illustrate with suitable examples primary and OLT . Clinical evaluation and multimodality imaging can be used secondary peritoneal neoplasms . in conjunction to diagnose these complications . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The peritoneal reflections and mesenteries divide E206. Perihepatitis: Various Causes and CT Findings the peritoneal cavity into various compartments . The circulation Kim, Y.1; Oh, S.1; Rha, S.1; Lee, Y.1; Jung, S.2; Byun, J.1; Lee, J.2 of the peritoneal fluid and rich blood supply provide an excellent 1. Kangnam St. Mary’s Hospital, Catholic University, Seoul, South vehicle for the dissemination of neoplasia . Peritoneal carcinoma- Korea; 2. St. Mary’s Hospital, Catholic University, Seoul, South tosis can be primary or secondary (metastatic) The. latter which is Korea more common occurs by direct spread, lymphatic dissemination, Address correspondence to Y. Kim ([email protected]) hematogenous embolic spread and peritoneal seedling . It is commonly associated with ascites and can cause bowel/ureteral Objective: The objective is to review the pathophysiology of peri- obstruction . In this exhibit we shall illustrate the characteristic hepatitis caused by various inflammatory processes and to dem- involvement of the peritoneum including fat stranding, omental onstrate the imaging findings of the perihepatitis on dynamic masses/nodules, peritoneal thickening, mesenteric nodules/ contrast-enhanced CT (CECT) . masses, scalloping of visceral surface by peritoneal nodules and Krukenberg’s tumor . Cross-sectional imaging affords the best Materials and Methods: This study included 38 patients (15 imaging option with both CT and MR providing excellent results . men, 23 women; age range, 15-72 years) with hepatic capsular enhancement identified by dynamic CECT . We analyzed the pres- Conclusion: This educational exhibit will illustrate the radiologi- ence and pattern of hepatic capsular enhancement, presence of cal spectrum of peritoneal carcinomatosis with emphasis on ana- subcapsular enhancement, presence of ascites and associated tomical aspects and etiopathogenesis . It is necessary for all prac- abnormalities in abdomen and pelvis on dynamic CECT . Imaging ticing radiologists to accurately identify often subtle peritoneal findings were correlated with medical records and pathological carcinomatosis due to its far reaching implications on diagnosis reports . and treatment .

246 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E208. MDCT of Retroperitoneal Air: What Lies Beneath? E209. When Pieces of the Pancreatic Puzzle Don’t Fit: (CME Credit Available) Discrepancies Between Multiphasic MDCT, 3D Datasets, Ojili, V.1; Shanbhogue, A.2; Nagar, A.1; Surabhi, V.3; Katabathina, Endoscopic Ultrasound, and Surgery (CME Credit Available) V.1; Prasad, S.1 1. University of Texas Health Science Center at Shulman, D.; Lockhart, M.; Eloubeidi, M.; Arnoletti, J.; Morgan, D. San Antonio, San Antonio, TX; 2. The Ottawa Hospital, Ottawa, University of Alabama at Birmingham, Birmingham, AL Canada; 3. University of Texas Health Science Center at Houston, Address correspondence to D. Morgan ([email protected]) Houston, TX Address correspondence to V. Ojili ([email protected]) Background Information: The only potentially curative treat- ment for patients with pancreatic adenocarcinoma is complete Background Information: Retroperitoneal air is an uncom- surgical resection . Using multiphasic MDCT, the sensitivity for mon finding of significant clinical importance . It is most com- detection of tumors and positive predictive value for determina- monly the result of bowel perforation secondary to inflamma- tion of unresectability approach 100% . However, detection of tory, ischemic or neoplastic causes, blunt or penetrating trau- tumors and accurate staging to properly select surgical candi- ma, foreign body, iatrogenic injury or a gas-producing infection dates remains a challenge in some patients . The purpose of this originating in retroperitoneal organs . As the fascial planes of exhibit is to demonstrate persistent pitfalls encountered despite the retroperitoneum are in continuity with those of the medi- using state-of-the-art pancreatic imaging techniques . astinum through the diaphragmatic hiatus, air from the neck and the mediastinum can also track into the retroperitoneum Educational Goals/Teaching Points: Sources of false positive or vice versa . Plain radiographs are the initial modality in eval- and false negative interpretations of resectable pancreatic tumors uation of acute abdomen and can depict retroperitoneal air will be demonstrated, including detection of isoattenuating non- and predict the possible cause with CT being the definite contour-altering tumors or tiny hepatic and peritoneal metastas- investigation . The purpose of this exhibit is to provide a es, as well as inaccuracies in estimation of vascular involvement detailed review of various causes of retroperitoneal air and to prior to or following neoadjuvant therapy . Emphasis will be discuss the role of MDCT in the evaluation of patients with placed on relative roles of multiphasic MDCT and MRI of the pneumoretroperitoneum . pancreas vs . endoscopic ultrasound (EUS), using surgically prov- en case material . The evolving issue of venous reconstructive sur- Educational Goals/Teaching Points: The goals are to provide gery and the impact that surgical technique variability has on the comprehensive review of various common and uncommon imaging determination of “resectable” vs . “unresectable” disease causes of retroperitoneal air; provide an overview of the anato- will be discussed . my of the extraperitoneal fascial planes and the retroperitoneal compartments, and discuss the role of MDCT in identifying the Key Anatomic/Physiologic Issues and Imaging Findings/ likely primary source of retroperitoneal air . Techniques: “3D surgical planning” pancreatic protocols have been proposed following the advances in isometric voxel acquisi- Key Anatomic/Physiologic Issues and Imaging Findings/ tion using MDCT . In addition to standard thin section axial images Techniques: Retroperitoneal tissues do not react as acutely and acquired during the pancreatic and portal venous phases, these severely to bacterial contamination as the peritoneal cavity . So it postprocessed images including thin section maximum intensity is not until retroperitoneal gas is recognized on MDCT that projection coronal and axial reformations, 3D volume rendered attention is directed to an acute process in the abdomen . CT angiography and CT venography, as well as curved multiplanar Imaging features of the distribution and localization of the retro- coronal reformations may help in assessment of tumor stage and peritoneal air provides an important clue to the identification of thus more accurate prediction of resectability . We reviewed our the primary source . MDCT is both highly sensitive and specific in experience enacting a “3D surgical planning pancreatic protocol” the detection of abnormal gas and is well suited for reliable and found inconsistencies between EUS, MDCT, and 3D images; depiction of the anatomic location, the extent of the gas and the these case examples will be used to the persistent difficulty underlying cause . The various causes discussed in this exhibit in imaging of pancreatic cancer patients . include the pathologies of retroperitoneal bowel and solid organs as well as rare conditions including aortitis, necrotic met- Conclusion: Knowledge of the potential pitfalls for accurate eval- astatic lymphadenopathy with air and retroperitoneal perforation uation of pancreatic cancer patients is critical . This exhibit will of gallbladder . demonstrate these imaging pitfalls encountered despite using state-of-the-art techniques . Conclusion: Though pneumoretroperitoneum by itself is not dangerous, prompt recognition of its origin is essential to unveil an underlying serious etiology . Distribution and location of the E210. Imaging of Pancreatitis: Prognostic Value of CT Findings retroperitoneal gas on CT provides an important clue to the Trout, A.; Elsayes, K.; Ellis, J.; Francis, I. University of Michigan, Ann identification of the likely source . MDCT plays a major role in Arbor, MI evaluating patients with pneumoretroperitoneum . Address correspondence to A. Trout ([email protected])

Background Information: Pancreatitis has multiple associated complications and findings that are apparent on CT evaluation . Several classification schemes have been developed to attempt to categorize outcomes in acute pancreatitis . In this exhibit, we will review CT findings of various subtypes and complications of acute pancreatitis with emphasis on the prognostic significance of these findings .

247 El e c t r o n i c Ex h i b i t s : Gastrointestinal

Educational Goals/Teaching Points: This exhibit will review the Conclusion: Non-neoplastic cystic tumors of the pancreas are epidemiology, pathophysiology and public health burden of rare lesions, aside from pseudocysts, which are increasingly iden- acute pancreatitis; briefly review the classification schemes used tified due to the more routine use and improved resolution of to stratify patients with acute pancreatitis; review the CT findings cross-sectional imaging . While an imaging diagnosis is often not of various subtypes of acute pancreatitis, including: uncomplicat- possible, familiarity with the features of these benign lesions is ed acute pancreatitis, groove pancreatitis, necrotizing pancreatitis, essential in forming a complete differential and guiding treat- and emphysematous pancreatitis, and review complications of ment . acute pancreatitis including: pseudocyst formation, peripancreat- ic/pancreatic abscess formation, and vascular complications such as pseudoaneurysm formation and venous thrombosis . Special E212. Heterotopic Pancreas in Various Locations: emphasis will be placed on the clinical context and prognostic Multimodality Imaging Features with Clinical and Pathologic significance of these findings to highlight those which are partic- Correlation ularly significant . Lee, J.1; Shin, K.1; Han, H.2; Cho, J.1; Kang, D.1 1. Chungnam National University Hospital, Daejeon, South Korea; 2. Eulji Key Anatomic/Physiologic Issues and Imaging Findings/ University Hospital, Daejeon, South Korea Techniques: Necrosis is the common pathway for most of the Address correspondence to K. Shin ([email protected]) prognostically significant imaging findings . It is important that contrast-enhanced CT is employed to identify the presence of Background Information: Heterotopic pancreas (HP) is seen necrosis identified by a lack of parenchymal enhancement fol- incidentally in approximately 2-5% of autopsies . The most fre- lowing contrast administration . The presence of gas within a peri- quent sites are the stomach and the duodenum . The jejunum is pancreatic fluid collection is a relatively specific sign of super-in- a less common site . It is rarely seen in the esophagus, mediasti- fection . Hemorrhage and pseudoaneurysm formation are typically num, gallbladder, omentum, spleen, fallopian tubes, and lymph delayed effects of pseudocyst formation and can result in signifi- nodes . It is usually asymptomatic . However, some patients have cant blood loss . epigastric pain, upper gastrointestinal bleeding, and occasional gastric outlet obstruction . In a few cases, the complications such Conclusion: Although pancreatitis is a common entity evaluated as pancreatitis, pseudocyst, cyst formation, insulinoma, adenoma, by CT, findings of necrosis and infection warrant special attention and malignant transformation, have been reported . Sometimes it due to their clinical significance and association with poor prog- is mistaken for a submucosal neoplasm . Therefore, It should be nosis . part of the differential diagnosis for a variety of abnormalities found at diagnostic imaging .

E211. Non-Neoplastic Cysts of the Pancreas (CME Credit Educational Goals/Teaching Points: The purpose of this exhibit Available) is to illustrate multimodality imaging features of heterotopic pan- Molvar, C.; Oto, A. University of Chicago, Chicago, IL creas in various locations with clinicopathologic correlation, Address correspondence to C. Molvar ([email protected]) and to understand advantage and limitation of each imaging modality . Background Information: Cystic lesions of the pancreas encom- pass a wide spectrum of pathologic entities with variable mor- Key Anatomic/Physiologic Issues and Imaging Findings/ phology, clinical behavior and pathogenesis . Familiarity with these Techniques: Thirty-seven patients (14 women, 23 men; mean lesions is essential since they are increasingly identified with the age, 42 years; age range, 6-75 years) with pathologically (n=33) more widespread use and the improved resolution of cross-sec- or clinically (n=4) proven heterotopic pancreas (HP) were identi- tional imaging . Cystic pancreatic masses are broadly classified into fied through a computerized search of radiologic and pathologic neoplastic and non-neoplastic cysts . Neoplastic cysts are consid- records at our institution from May, 1994 to August, 2008 . A ret- ered malignant or premalignant, except for serous cystadenomas, rospective review of radiologic and clinical findings was per- which are almost always benign . Conversely, non-neoplastic cysts formed . The locations of HP were as follows: 25 at stomach, six at have no malignant potential . Management strategies for many duodenum, three at jejunum, two at ileum, and one at urachus . pancreatic cysts are controversial due to their uncertain natural The clinical presentations were as follows: pancreatitis (n=3), history and the frequent lack of a preoperative diagnosis . Although intussusception (n=1), epigastric pain (n=11) melena (n=2), and preoperative differentiation of neoplastic and non-neoplastic jaundice (n=1) . The remaining 19 patients were asymptomatic . lesions is often not possible, awareness with the disease spec- In two cases, HP showed malignant transformation pathologically . trum and key features of cystic pancreatic masses is important . Imaging modalities such as MDCT, upper gastrointestinal series, hypotonic duodenography, barium enema, Meckel’s scan, MRI Educational Goals/Teaching Points: This review describes and endoscopic ultrasound were used . We performed a retro- the clinical presentation, histology, and imaging findings of non- spective review of radiologic findings of HP in various locations neoplastic cystic lesions of the pancreas . In addition, treatment with clinicopathologic correlation and review of literature . options for several of these lesions are explored . Conclusion: This exhibit will enhance the radiologists under- Key Anatomic/Physiologic Issues and Imaging Findings/ standing regarding pathophysiology and radiologic features of Techniques: We report the CT and MRI findings of non-neoplas- HP . Familiarity with this anomaly, the imaging techniques availa- tic pancreatic cysts; specifically, pseudocysts, retention cysts, ble for its study, and its variable imaging manifestations may be benign epithelial cysts, abscesses, duodenal wall cysts (diverticu- useful in making the correct diagnosis . la), lymphoepithelial cysts and the recently described mucinous non-neoplastic cyst .

248 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E213. Severe and Unusual Forms of Acute Pancreatitis: Educational Goals/Teaching Points: The goals are to describe Spectrum of CT Findings with Emphasis on Complication the normal anatomy and related structures on imaging; illustrate Shin, K.1; Lee, J.1; Han, H.2; Cho, J.1 1. Chungnam National the array of disease processes affecting the pancreatic groove on University Hospital, Daejeon, South Korea; 2. Eulji University imaging; assess utility of reformatted images; propose an imag- Hospital, Daejeon, South Korea ing based approach, and understand the role of imaging in man- Address correspondence to K. Shin ([email protected]) agement planning .

Background Information: Acute pancreatitis is a self-limited Key Anatomic/Physiologic Issues and Imaging Findings/ disease in many patients . At the other end of the spectrum, it is Techniques: The exhibit includes normal anatomy; imaging an unpredictable illness with an appreciable incidence of severe appearance of various pathologies affecting the pancreas, duode- complications and death . Accurate diagnosis is not easy in some num, lymph nodes, common bile duct, vascular structures, mis- unusual forms . Early recognition of pancreatitis and its complica- cellaneous; imaging modalities, reformatted images and optimal tion is critical, because proper management of the patient applications; pitfalls and mimics on imaging; imaging algorithm remains a formidable challenge . CT is the imaging technique of to various disease processes, and the role of imaging in manage- choice for confirming the diagnosis and detecting complication . ment planning .

Educational Goals/Teaching Points: The goals are to illustrate Conclusion: A spectrum of aggressive and nonaggressive patho- and assess the imaging findings of acute pancreatitis with logical processes can affect the pancreatic groove . Imaging has a emphasis on its complication in severe and unusual forms, and potential role to play in differentiating structure of origin and dis- illustrate and assess the imaging findings of acute pancreatitis ease processes . Various imaging modalities can be used prudent- with emphasis on its complication in severe and unusual forms . ly and optimally to elucidate this gray zone and guide appropri- ate management . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: We retrospectively reviewed the imaging findings of severe acute pancreatitis . CT allows the detection of pancreatic E216. MRI of the Pancreas: State-of-the-Art necrosis, hemorrhage and abscess and demonstrates the spread Sebastian, S.; Krishnamoorthy, S.; Kalb, B.; Rostad, B.; Li, J.; of inflammatory process into adjacent retroperitoneal and sub- Salman, K.; Sharma, P.; Adsay, V.; Sarmiento, J.; Martin, D. Emory peritoneal spaces . Hemorrhagic pseudocyst, pseudocyst mimick- University, Atlanta, GA ing cystic tumor, pseudocyst with calcification are demonstrated . Address correspondence to S. Krishnamoorthy (saravanan. CT is helpful determining the route of percutaneous drainage of [email protected]) deeply located pseudocyst . Extensive inflammatory extension toward adjacent organs (i .e ., spleen, stomach, duodenum, colon, Background Information: Common pancreatic diseases range and gallbladder) results in tissue destruction, severe mural from infectious or inflammatory conditions to benign or malig- edema, and fistula formation into various sites (mediastinum, nant neoplastic masses . With superior soft tissue detail and high peritoneal cavity, hollow viscus) . Unusual form of acute pancrea- sensitivity to acute as well as chronic processes, MRI allows the titis include post-traumatic or endoscopic retrograde cholangio- radiologist to elucidate pancreatic diseases . pancreatography, pancreatitis, pancreatitis related to choledochal cyst and tumor, pancreatitis mimicking carcinoma, and groove Educational Goals/Teaching Points: The goals are to define a pancreatitis . Other significant complications include biliary comprehensive MRI protocol for pancreatic imaging; differentiate obstruction mimicking common bile duct, cancer, thrombosis in acute from chronic pancreatitis and delineate complications of splenic vein, and splenic arterial aneurysm . pancreatitis; understand the features of benign pancreatic masses on MRI, including masses that require followup imaging, and Conclusion: CT is able to delineate the spreading route of identify malignant pancreatic masses, including features that cor- inflammatory process and accurately identify the complications of relate with the histologic diagnosis, and patterns of metastatic acute pancreatitis . In some unusual form, malignancy should be disease . differentiated . Familiarity with these imaging findings is necessary for the proper management and thus to avoid catastrophic clini- Key Anatomic/Physiologic Issues and Imaging Findings/ cal outcomes . Techniques: Fast sequences with reproducible and homogenous fat suppression are vital for pancreatic imaging . Proper timing of the arterial phase post gadolinium sequences in conjunction with E214. Imaging Approach to Lesions of Pancreatic Groove subsequent multiphasic postgadolinium sequences are integral With Radiologic-Pathologic Correlation to identifying chronic pancreatitis and pancreatic adenocarcino- Sainani, N.; Catalano, O.; Mino-Kenudson, M.; Forcione, D.; ma . Acute pancreatitis alters the appearance of the pancreatic Sahani, D. Massachusetts General Hospital, Boston, MA parenchyma and surrounding retroperitoneal fat on T2 fat sup- Address correspondence to N. Sainani ([email protected]) pressed sequences . Acute complications can be discerned by similar inflammatory changes . Metastatic disease to the liver has Background Information: Pancreatic groove or pancreatoduo- characteristic appearances that often correlate with the type of denal groove is a narrow potential space bordered by important pancreatic malignancy . Vascular encasement limits surgical treat- structures . A spectrum of aggressive and nonaggressive patholog- ment options for pancreatic adenocarcinoma . ical processes can affect the pancreatic groove . Imaging has a potential role to play in differentiating structure of origin and dis- Conclusion: With superlative soft tissue contrast, fast updated ease processes . Imaging can be used prudently and optimally to MRI techniques, and a comprehensive protocol, MRI can deline- elucidate this gray zone and guide appropriate management . ate pancreatic diseases with high sensitivity and reproducibility .

249 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E218. Multimodality Imaging of the Pancreas Transplant: A Key Anatomic/Physiologic Issues and Imaging Findings/ Pictorial Review of the Expected Postoperative Imaging Techniques: The exhibit will describe the location of the primary Appearance and Complications neoplasm within the pancreas (head, neck, body, tail, and/or Downey, R.; Dillman, J.; Elsayes, K.; Bude, R.; Platt, J.; Francis, I. uncinate); enhancement characteristics on contrast-enhanced University of Michigan Health Center, Ann Arbor, MI MRI and CT; vascular involvement (portal vein, superior Address correspondence to R. Downey ([email protected]. mesenteric vein, splenic vein, hepatic artery, celiac axis, superior edu) mesenteric artery, gastroduodenal artery) and the relationship to surgical respectability; invasion of adjacent organs (common bile Background Information: A growing number of pancreas trans- duct, stomach, duodenum, colon) and the relationship to surgical plantations are being performed in the United States for the respectability, and metastatic spread (liver, lungs, lymph nodes, treatment of insulin-dependent diabetes mellitus . Consequently, intraperitoneal) . the radiologist must be well-acquainted with the normal imaging appearance of the post-transplant pancreas along with the spec- Conclusion: Pancreatic adenocarcinoma is a significant cause of trum of possible transplant-related complications . cancer morbidity and mortality in the United States . Radiology plays an important role in the team approach to prompt diagno- Educational Goals/Teaching Points: To discuss the utility of sis, staging, and approach to therapy . Knowledge of the typical, various imaging modalities in the assessment of the post-trans- as well as atypical, radiographic findings of disease and their plant pancreas and to provide representative examples of normal impact on therapeutic decision making is a necessary skill for and abnormal postoperative radiological findings . practicing radiologists .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Indications for pancreatic transplantation along with E220. PET-CT of the Pancreas: Lesion Detection, transplantation surgical technique are reviewed . The various Characterization, Surgical Planning and Response imaging modalities used to evaluate pancreas transplants as well Assessment as the indications for each are discussed . The uncomplicated Cronin, C.; Catalano, O.; Blake, M.; Mueller, P.; Sahani, D. post-transplantation appearance of the pancreas by ultrasound, Massachusetts General Hospital, Boston, MA CT and MRI is described . Radiological findings of post-transplan- Address correspondence to C. Cronin (carmelcronin2000@hot- tation complications, including graft vascular thrombosis, graft mail.com) vessel compression, graft rejection, peritransplant fluid collec- tions, pancreatic duct anastomotic leak/pseudocyst formation, Background Information: The goals are to provide an educa- pseudoaneurysm and post-transplant lymphoproliferative disor- tional and pictorial review of the PET-CT imaging manifestations, der are also provided . distribution and classification of pancreatic malignancy namely pancreatic adenocarcinoma, metastasis, lymphoma, islet cell Conclusion: Pancreatic transplantation has become more com- tumors, and less common pancreatic malignancies such as intra- monplace over the past several decades, and as such, familiarity ductal papillary mucinous neoplasms, and to illustrate and with the expected postoperative graft appearance as well as pos- describe PET-CT’s impact on surgical planning and disease sible transplant-related complications is increasingly important . response assessment of these pancreatic malignancies . Ultrasound, CT and MRI are useful in the evaluation of pancreas transplants . Educational Goals/Teaching Points: PET-CT has revolutionized disease understanding, disease assessment, staging, treatment E219. Pancreatic Cancer: A Review of the Radiology of and response assessment . In this pictorial review we consider the Diagnosis, Staging, and Treatment (CME Credit Available) range of neoplastic pathologies that may be detected by this Schabel, A.; Shaaban, A. University of Utah, Salt Lake City, UT imaging modality and review their clinical, pathological and PET- Address correspondence to A. Schabel ([email protected]. CT imaging manifestations . We discuss differentials where appro- edu) priate, in particular in differentiating the various pancreatic malig- nancies . Background Information: Pancreatic cancer is the fourth lead- ing cause of cancer mortality in the United States with 34,290 Key Anatomic/Physiologic Issues and Imaging Findings/ fatalities in 2008 . Additionally, with a five year survival rate of less Techniques: Through our institutional experience and a review than 5%, it has one of the worst prognoses of any cancer sec- of literature we will provide a diverse review of PET-CT’s role in ondary to the generally advanced stage at the time of diagnosis . pancreatic disease diagnosis and management . Radiology plays an essential role in prompt diagnosis, staging, and therapy monitoring . This presentation will provide a review Conclusion: The important factors of better disease staging and of the regional anatomy, pathophysiology, diagnosis, staging, more accurate response assessment offered by PET-CT imaging management, and therapy of pancreatic adenocarcinoma . allows for more appropriate disease management and treatment of pancreatic disease . We provide an interesting, informative and Educational Goals/Teaching Points: The goals are to review concise radiological guide . the regional anatomy; pathophysiology of pancreatic adenocarci- noma; radiological methods and findings in the diagnosis and staging (CT, MRI, PET-CT) of pancreatic adenocarcinoma; routes of disease spread (local invasion, lymphatic, hematogenous, intraperitoneal); specifics of disease staging; therapy based on disease staging, and complications related to disease and/or therapy . 250 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E221. Pelvic MRI for Perineal Crohn’s Disease: A Pictorial 58 .2 years) with 25 SHs (size range: 0 8-10. 1;. mean: 2 2. cm)– Essay (CME Credit Available) confirmed by splenectomy (n=2), CT (n=18) and/or MRI Labat, E.; Ballester, G.; Colon, E.; Gomez, A.; Devesa, N.; Lopez- (n=13)–evaluating baseline and contrast-enhanced findings of Alvarez, Y. University of Puerto Rico, Guaynabo, PR each lesion in comparison with adjacent spleen parenchyma . Address correspondence to G. Ballester ([email protected]) Results: At baseline US, 19/25 (76%) lesions showed homoge- Background Information: Crohn’s disease (CD) is a chronic, neous echo texture, mainly hyperechoic (n=14) . In all cases transmural inflammatory process of the gastrointestinal tract . The round contours were observed with well-defined borders in most common perineal manifestations are perianal fistulas and 24/25 (96%) SHs . Color-Doppler imaging did not show any sig- abscesses . In up to 25% of patients, fistulas may precede the nal in 20/25 (80%) hemangiomas . At CEUS, nine out of 25 SHs intestinal manifestations . MRI with its high soft tissue contrast, showed an isoechoic appearance throughout the vascular phase; multiplanar capabilities and spatial resolution, is the most specif- two out of 25 were hypoechoic in arterial phase becoming isoe- ic and sensitive tool for the diagnosis of perineal complications in choic in the remaining phase, whereas one out of 25 SH was iso- fistulizing Crohn’s disease . MRI can reveal the location, extent, echoic in the arterial phase but became hypoechoic in portal-ve- and severity of the inflammatory reaction . Assessment for the nous and delayed phases . Four out of 25 SHs showed a rapid presence and severity of perianal fistulas in Crohn’s disease is and complete fill-in in the arterial phase, but appeared isoechoic important for patient management and prognosis . The purpose (n=2) and hypoechoic (n=2) in delayed phase respectively . Two of this exhibit is to review the anatomy of the pelvic floor and out of 25 SHs showed peripheral hyperechoic nodules in the perineum; described an MRI protocol for the evaluation of the arterial phase, followed by progressive centripetal fill-in . Finally, pelvic floor and perineum in patients with CD in a 1 .5T magnet, seven out of 25 hemangiomas appeared constantly hypovascular . and emphasize the role of MRI for the demonstration of perineal complications in CD . Conclusion: When a splenic mass is discovered during an US performed for other reasons, in the absence of history of cancer, Educational Goals/Teaching Points: The complex pelvic floor a primary benign vascular neoplasm should be considered and anatomy can be accurately evaluated with MRI . Pelvic MRI is the hemangioma is the most common focal splenic lesion . At CEUS, most useful imaging technique for accurate assessment of peri- the majority of SHs presents contrast-enhancement patterns simi- neal CD . Pelvic MRI plays a major role in the diagnosis and clas- lar to that of liver hemangiomas . sification of fistulas in CD, which is used to guide therapeutic interventions and is very useful for prognosis . E223. Submucosal Tumors of the Stomach: Differentiation of Key Anatomic/Physiologic Issues and Imaging Findings/ Gastric Schwannoma from Gastrointestinal Stromal Tumor Techniques: The exhibit will include a brief discussion of the With CT pathophysiology in perineal Crohn’s disease; a description of the Choi, J.1; Choi, D.1; Liu, W.2 1. Samsung Medical Center, Seoul, pelvic floor MRI protocol for the evaluation of perineal CD; a South Korea; 2. Wooridul Spine Hospital, Seoul, South Korea review the anatomy of the pelvic floor and the perineal compart- Address correspondence to C. Jin Wook ([email protected]) ments, and a review the classifications of perianal fistulas and its MRI correlation . Objective: The goal is to describe CT findings of gastric schwan- noma (GS) and determine characteristics that distinguish GS Conclusion: The role of MRI to evaluate perineal disease activity from gastrointestinal stromal tumor (GIST) . in CD has been investigated extensively, as MRI has intrinsic advantages over other techniques, including noninvasiveness, the Materials and Methods: A total of 130 patients who underwent absence of ionizing radiation and a superb contrast resolution . contrast-enhanced CT and were confirmed to have GS (n=5) or Noncontrast and contrast-enhanced MRI evaluation of the pelvic GIST (n=105) were assessed retrospectively . Two experienced floor and perineal region can define the localization and extent radiologists reviewed CT findings of those patients in consensus . of fistulas . MRI can accurately show the pelvic and perineal com- The size, contour (round or lobulated), surface (regular or irregu- plications of CD and help to establish the best patient manage- lar), location with respect to the bowel wall (intraluminal, mixed, ment . Ultimately, radiologists should have a thorough knowledge or exophytic), enhancement degree (poor, moderate, or well), of the pelvic floor anatomy and the common MRI findings in enhancement pattern (homogeneous or heterogeneous) were perineal CD . documented . We also evaluated for the presence of necrosis, hemorrhage, calcification or ulceration .

E222. Role of Contrast-Enhanced Ultrasound in the Results: There were significant differences in surface and loca- Assessment of Splenic Hemangiomas tion with respect to the bowel wall between GS and GIST . Bartolotta, T.; Taibbi, A.; Galia, M.; Lo Re, G.; La Grutta, L.; Bova, Irregular surface is seen in no patient (0%) with GS and 22 V.; Midiri, M.; De Maria, M. University Hospital, Palermo, Italy patients (21 4%). with GIST, respectively . Intraluminal growing Address correspondence to A. Taibbi ([email protected]) masses were seen in no patient with GS (0%) and 24 patients (23 3%). with GIST, respectively . There were no significant differ- Objective: The goal is to illustrate contrast-enhancement pat- ences in size, contour, enhancement degree, enhancement pat- terns of splenic hemangiomas (SH) at contrast-enhanced ultra- tern, presence of necrosis, hemorrhage, calcification or ulceration sound (CEUS) . between GS and GIST .

Materials and Methods: Two experienced radiologists retro- Conclusion: GS and GIST showed similar imaging findings . spectively reviewed baseline and sulphur hexafluoride-enhanced Location with respect to the bowel wall and surface irregularity ultrasound (US) of 25 patients (14 women, 11 men; mean age: may helpful to differentiate GS from GIST . 251 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E224. Gastrointestinal Carcinoid Tumors and Mesenteric Educational Goals/Teaching Points: The goal is to illustrate Abnormalities: The Spectrum of Radiological Appearances the imaging characteristics of GISTs across the range of imaging Bharwani, N.; Druce, M.; Grossman, A.; Reznek, R.; Rockall, A. modalities and describe in detail the use of embolization in the Barts and The London NHS Trust, London, United Kingdom treatment of GIST . Address correspondence to N. Bharwani (nishatbharwani@gmail. com) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: We have performed a retrospective review of more Objective: One of the hallmarks of mid-gut carcinoid tumors is than 45 cases of GIST over a ten-year period . Cases of GIST aris- the occurrence of fibrosis both locally and distant from the pri- ing in the esophagus, stomach, small intestine and colon are dis- mary tumor . In the mesentery this can result in a marked desmo- cussed . The typical imaging characteristics on CT, MRI, ultrasound plastic reaction . Fibrosis can also occur at other sites, for exam- and barium studies are reviewed . We also present a case of a ple, the retroperitoneum, pleura, skin and cardiac valves . The eti- rare duodenal GIST embolized with micro-particles . ology of carcinoid fibrosis is thought to involve serotonin proba- bly via the 5HT2B receptor and downstream pathways . Although Conclusion: GISTs are well demonstrated using a number of features of carcinoid heart disease have been well documented, imaging modalities . These can be used both for initial diagnosis the prevalence and clinical significance of intra-abdominal fibro- and staging and for follow-up . In addition, interventional radiolo- sis has been reported in very few series . Our study aims to evalu- gy plays a role in the active management of some cases of GIST . ate this further .

Materials and Methods: We included all patients with mid-gut E226. Imaging Evaluation for Internal Hernia in carcinoid tumors and available imaging over the past eight years . Laparoscopic Roux-en-Y Gastric Bypass Patients – A Notes were reviewed for demographic characteristics, history of Difficult but Essential Diagnosis (CME Credit Available) small bowel obstruction and biochemical investigations . The Umphrey, H.; Lockhart, M.; McArthur, T.; Clements, R.; Robbin, M.; available imaging was reviewed for mesenteric abnormalities, in Canon, C. University of Alabama at Birmingham, Birmingham, AL particular those characteristically associated with carcinoid Address correspondence to H. Umphrey ([email protected]) tumors . Where imaging of other sites was also available the occurrence of extra-abdominal fibrosis was sought . Background Information: Obesity is an important public health problem in the United States and is associated with significant Results: Thirty-two patients were included in the study, 16 men morbidity . Surgical approaches to therapy, bariatric procedures, and 16 women . Sixteen patients (50%) had a mesenteric mass . are routinely used to treat patients with morbid obesity (body The mass was associated with coarse calcification in seven mass index [BMI] greater than 40 or BMI>35 with comorbidity) . patients, surrounding soft tissue stranding in 11 patients and Internal hernia after laparoscopic Roux-en-Y gastric bypass “indrawing” of tissues in nine patients . Five of the 16 patients (LRGB) is an uncommon but clinically significant complication, as had all three of these associated features . One further patient it can progress to volvulus and small bowel infarction . It is more had soft-tissue stranding without a visible mass . Eleven of 32 common after LRGB as opposed to open procedures . It is a chal- patients (34%) had small bowel thickening and one had small lenging diagnosis both clinically and with imaging, and ideally bowel separation . Two patients had a “misty” mesentery and two should be identified before patients present with obstruction to patients had early retroperitoneal fibrosis . Three patients had assure best outcome . incidental evidence of extra-abdominal fibrosis (pleural thicken- ing) . In 27 of 32 patients (78%), imaging confirmed the presence Educational Goals/Teaching Points: This exhibit will describe of liver metastases . There was no correlation of mesenteric pertinent abdominal anatomy post LRGB; prescribe appropriate involvement with gender or with mean 24-hour urinary 5-hydrox- imaging evaluation of these patients; list complications after yindole acetic acid value . Of the patients with radiological fibro- LRGB, and analyze imaging findings associated with internal sis, 31% had a history of small bowel obstruction, in comparison hernia . to 7% in the group without fibrosis (p>0 .05) . Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: Intra-abdominal fibrosis is a hallmark of mid-gut Techniques: CT findings of internal hernia post LRGB include: 1) carcinoid and can be detected radiologically in approximately swirled appearance of the mesenteric fat or vessels at the 50% of patients . This is more common in association with a pre- mesenteric root, 2) clustered loops of small bowel, 3) small vious clinical presentation of small bowel obstruction . bowel obstruction, 4) mushroom shape of herniated mesenteric root with crowding and stretching of the mesenteric vessels, 5) round shape of the herniated mesenteric fat closely surrounded E225. Gastrointestinal Stromal Tumors: A Review of the by bowel loops, 6) small bowel other than duodenum passing Imaging Findings posterior to the superior mesenteric artery, and 7) distal jejunal Knox, M.; Beddy, P.; Murphy, G.; Ryan, J.; McDermott, R.; Meaney, anastomosis located in the right aspect of the abdomen . J. St. James’s Hospital, Dublin, Ireland Address correspondence to M. William ([email protected]) Conclusion: Internal hernia is an ominous complication of LRGB; therefore, it is essential to have a commanding knowledge Background Information: Gastrointestinal stromal tumors of the postsurgical anatomy and be skilled in identification of the (GISTs) are mesenchymal tumors arising from the muscularis axial imaging signs of internal hernia unique to this patient pop- propria layer, which can occur throughout the gastrointestinal ulation . (GI) tract . They comprise less than 1% of all GI tumors . GISTs commonly arise in the stomach, small intestine and colon . Less common sites include the esophagus and mesentery . 252 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E227. The Roux-en-Y Gastric Bypass: Normal Anatomy and includes Roux-en-Y gastric bypass, laparoscopic adjustable gastric Complications; A Comparison of Operative and Radiographic banding, vertical-banded gastroplasty, gastric sleeve bypass, and Findings (CME Credit Available) lesser used surgical procedures . Laparoscopic adjustable gastric Cardoza, S.; Tsai, L.; Angus, L.; Scarmato, V. Nassau University banding is being performed increasingly in the United States Medical Center, East Meadow, NY since FDA approval in 2001 . Address correspondence to S. Cardoza (supriyacardoza@yahoo. com) Educational Goals/Teaching Points: The exhibit will discuss the epidemic problem of obesity and the surgical options availa- Background Information: Morbid obesity is one of the com- ble; describe the technical details of laparoscopic adjustable gas- mon and debilitating health problems in the United States . The tric banding; identify the early and late complications of adjusta- increasing prevalence, especially in a younger age group, and ble gastric banding, and review the role of imaging in patients associated increased morbidity and mortality, continues to have a following gastric banding . significant impact on overall healthcare costs . Nonsurgical treat- ments like education, diet, exercise, and pharmacological inter- Key Anatomic/Physiologic Issues and Imaging Findings/ vention have had disappointing results . Bariatric surgery has Techniques: At our institution, laparoscopic adjustable gastric emerged as a reliable method of weight reduction . Roux-En-Y banding has become a popular alternate to other bariatric surgi- gastric bypass surgery, introduced by Mason and Ito in 1967, has cal procedures . Gastric banding is a pure ‘restrictive’ procedure, seen an exponential increase in the number of procedures per- and the degree of restriction can be easily altered or the band formed . It is now imperative for the radiologist to become famil- removed, if necessary . In this exhibit, the indications and tech- iar with normal postsurgical anatomy and the spectrum of possi- niques of laparoscopic adjustable gastric banding are discussed ble complications . and illustrated . The normal appearances of gastric banding are shown on plain abdominal imaging, and on standard contrast Educational Goals/Teaching Points: Our goals in this presenta- and CT examinations . In addition, potential early and late compli- tion are to correlate key surgical anatomy of the most common cations are reviewed and the role of imaging in identifying and bariatric surgery, the Roux-En-Y gastric bypass, using intraopera- managing these problems is discussed and illustrated . tive photographs with the radiologic findings on MDCT upper gastrointestinal studies . We will also illustrate the spectrum of Conclusion: Laparoscopic adjustable gastric banding is one of postoperative complications of this surgery . the newly approved bariatric ‘restrictive’ surgeries in the United States . The procedure has gained in popularity in recent years, Key Anatomic/Physiologic Issues and Imaging Findings/ but is not without potential complications . Radiologic imaging Techniques: We will illustrate key surgical steps of Roux-en-Y plays an important role in evaluating patients following gastric gastric bypass surgery; the gastric reservoir creation, Roux limb banding to assess both normal and abnormal anatomy . creation, gastrojejunostomy anastomosis, and distal Roux to bili- opancreatic limb anastomosis . Both intraoperative photographs and post operative radiological images will be used to correlate E230. The “O” Sign, a Helpful Tool in the Diagnosis of the normal post surgical anatomy . We retrospectively reviewed Laparoscopic Gastric Band Slippage. 400 Roux-en-Y gastric bypass surgeries performed at our institu- Pieroni, S.; Sommer, E.; Burch, M.; Tkacz, J. Boston University tion for postoperative complications, both immediate and long Medical Center, Boston, MA term . We demonstrate examples of anastomotic leaks, strictures, Address correspondence to S. Pieroni ([email protected]) marginal ulcers, acute gastric distention, gastrogastric fistulas, small bowel obstruction and internal hernias . Objective: The purpose of this scientific exhibit is to describe a sign on plain film radiography for gastric band slippage, a known Conclusion: With the steadily increasing number of bariatric sur- complication of the laparoscopic adjustable gastric banding sur- geries performed in the United States, the probability of a radiol- gery and to emphasize the importance of this finding to radiolo- ogist encountering a postoperative patient, either in routine or gists and clinicians . emergency settings, has similarly increased . It is essential to understand the normal postsurgical anatomy, clinical course and Materials and Methods: We reviewed the radiological findings common complications so as not to misinterpret radiological in 55 consecutive patients who underwent the laparoscopic gas- examinations . Understanding the surgical process will allow the tric banding surgery . Between March, 2007 and September, 2008, radiologist to better understand the normal anatomy, diagnose four patients were diagnosed at our institution with gastric band complications and communicate with the referring clinicians . slippage . All patients underwent a barium upper gastrointestinal (UGI) examination at the time of presentation to the emergency room . Based on radiographic findings and/or clinical concern, all E228. Laparoscopic Gastric Banding: Techniques, patients were explored in the operating room . Complications, and Imaging (CME Credit Available) Ott, D.; Oliphant, M.; Fernandez, A. Wake Forest University Results: On the initial scout abdominal plain film image, all four Medical Center, Winston Salem, NC of the patients with surgically proven gastric band slippage dem- Address correspondence to D. Ott ([email protected]) onstrated an “O” shaped configuration of the gastric band, (the “O” sign) . In all 4 cases, a baseline UGI examination was availa- Background Information: Obesity has become an epidemic ble for comparison . In all of these cases, the “O” configuration of health problem and bariatric surgical procedures are now being the slipped gastric band was a change from the proper band performed commonly and at increasing frequency . In addition to position, a rectangular appearance with the long axis of the band historic surgeries for obesity, the current spectrum of procedures oriented at an acute angle with respect to the spine .

253 El e c t r o n i c Ex h i b i t s : Gastrointestinal

Conclusion: As laparoscopic adjustable gastric banding surgery Educational Goals/Teaching Points: The goals are to accurately becomes increasingly used, more and more patients are present- protocol CT and contrast fluoroscopy examinations in com- ing to the emergency room with complications of the procedure, plex postoperative gastrointestinal patients; identify radiographic particularly as a result of slippage of the gastric band . As the con- findings of postoperative leaks and fluid collections; avoid con- sequences of slippage may require acute surgical intervention, it trast fluoroscopy pitfalls, including failure of adequate patient is imperative that the radiologist be familiar with the surgical positioning, and accurately identify foreign bodies . technique and appearance of the correct and incorrect position- ing of the gastric band . Identification of the “O” sign on plain film Key Anatomic/Physiologic Issues and Imaging Findings/ radiography can potentially aid the radiologist, surgeon or emer- Techniques: Protocoling of imaging studies remains an integral gency room physician to the early detection of gastric band slip- process in accurate and timely postoperative imaging . Selection page and appropriate patient triage . of appropriate examination technique and contrast agent is imperative . In contrast fluoroscopy, the importance of patient positioning and repositioning cannot be underscored enough . E231. Signs in Gastrointestinal Radiology: An Interactive Teaching File Part I Plain Film and Barium Studies (CME Conclusion: The radiologist’s role in the increasingly complex Credit Available) postoperative patient continues to grow . If we are to remain inte- Bloomer, C.1; Hartman, D.1; Hartman, M.2 1. Penn State, gral in this process, we must provide timely, accurate imaging Harrisburg, PA; 2. Allegheny General Hospital, Pittsburgh, PA diagnoses . Address correspondence to C. Bloomer ([email protected])

Background Information: Metaphorical signs are commonly E233. Spectrum of Findings on Defecography Using High used in the day-to-day practice of all aspects of diagnostic radiol- Quality Digital Fluoroscopy ogy . These signs frequently serve as a mnemonic to suggest a Ruma, J.; Al-Hawary, M.; Kaza, R.; Liu, P.; Cohan, R.; Weadock, W.; specific diagnosis or limited differential diagnosis . Sonda, P. University of Michigan, Ann Arbor, MI Address correspondence to M. Al-Hawary ([email protected]) Educational Goals/Teaching Points: The exhibit is auto-tutorial . A series of cases demonstrating a sign encountered in gastroin- Background Information: Observation of the normal and testinal radiology will be presented . This will be followed by an abnormal findings found during defecography relies on the explanation of the sign, a metaphorical illustration and the most dynamic observation of the pelvic structures motion during real- common diagnosis or differential diagnosis associated with that time fluoroscopy in order to make the appropriate diagnosis . sign . Some of the signs will include: bird’s beak (esophagus and Both radiologic diagnostic observation and communication of the colon), reverse three (esophagus and duodenum), feline esopha- abnormal findings to the referring physician is difficult using still gus, football, leather bottle, stalactite, Carmen’s meniscus, ram’s images or even videotape from defecography procedures . horn, pad, soap bubble, windsock, cloverleaf, hidebound appear- Interpretation efficiency can be enhanced using digital fluorosco- ance, cobblestone, apple peal, picket fence, bull’s-eye, aneurys- py with improved image quality edited for physician review in a mal dilatation, coiled spring, stacked coin, stripe, northern expo- format suitable for transmission to both the PACS and subse- sure, southern exposure, bowler hat, collar button, apple core, quently through the Internet . thumb printing, and double track . Educational Goals/Teaching Points: The goal is to demonstrate Key Anatomic/Physiologic Issues and Imaging Findings/ the normal anatomy and different abnormalities noted on defec- Techniques: The exhibit will include: anatomy (the hollow vis- ography using digital fluoroscopy format for enhanced visualization cera of the gastrointestinal tract—esophagus, stomach, small of the dynamic findings observed during real-time fluoroscopy . intestine, large intestine) and imaging techniques (plain film and barium studies of the organs listed above) . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The normal anatomy and different types of abnor- Conclusion: This exhibit will enable users to familiarize them- mal defecation causing either constipation or incontinence as selves with signs in gastrointestinal radiology as well as a limited observed during defecography will be illustrated . Emphasis will be differential diagnosis for each sign . placed on the relationship and movement of the different pelvic structures during the different dynamic phases of fecal control and evacuation . Pathognomonic features of common disorders such E232. Postoperative Gastrointestinal Tract: Leaks, Fluid as rectoceles, enteroceles, rectal prolapse and intussusception Collections and Foreign Bodies which can be identified during defecography will be presented . Smith, J.; Lockhart, M.; Canon, C. University of Alabama at Birmingham, Birmingham, AL Conclusion: Understanding of pelvic motion during defecation is Address correspondence to C. Canon ([email protected]) enhanced using high quality digital fluoroscopic formatting . Such formatting enhances the detection of pathologic conditions lead- Background Information: The number of gastrointestinal sur- ing to constipation or fecal incontinence, thus improving the abil- geries continues to grow . Patients are increasingly complex and ity to communicate findings to the referring physician for subse- difficult to clinically evaluate . As a result, imaging has moved to quent treatment decisions . the forefront of postoperative patient care . Simply diagnosing postoperative fluid collections is no longer adequate . Imagers must be facile in postsurgical anatomy, expected imaging find- ings, and complications .

254 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E234. MR Imaging of Organ Iron Deposition: Physical Educational Goals/Teaching Points: The goals are to illustrate Principles and Clinical Utility the spectrum of iron containing abdominal pathology, and dem- Romano, P.; Stephenson, M.; Hanley, M.; Hardie, A. Medical onstrate the effects of, including the pitfalls caused by, variable University of South Carolina, Charleston, SC echo-time used for out-of-phase and in-phase MR imaging on Address correspondence to A. Hardie ([email protected]) characterizing these entities .

Background Information: Iron deposition in the abdominal Key Anatomic/Physiologic Issues and Imaging Findings/ organs occurs in congenital disorders of iron metabolism as well Techniques: On dual phase gradient echo sequences, a shorter as in patients receiving chronic blood transfusions, often termed echo time for out-of-phase imaging can help distinguish between secondary hemosiderosis . However, it is increasingly being appre- lipid containing lesions (lose signal on out-of-phase) and iron ciated that patients with liver cirrhosis also can have abnormal containing lesions (lose signal on in-phase) . But, if the out-of- iron deposition, not only in the liver but other abdominal organs . phase sequence is acquired with a longer echo time than the in- Some authors suggest that the presence of hepatic iron in cirrho- phase sequence, it will be difficult to distinguish signal loss sis may increase the risk for hepatocellular carcinoma and may caused by the coexistence of lipid and water in the same voxel, need to be treated . The purpose of this educational exhibit is to and that due to susceptibility effect from iron . present the physical principles of MRI that can allow for not only iron detection but quantification . Also, case examples will be pre- Conclusion: Magnetic susceptibility artifact is useful to diagnose sented which demonstrate how iron deposition can be quanti- iron containing lesions on MRI . The echo time used for out-of- fied in the liver and other abdominal organs . phase imaging relative to in-phase is important to distinguish between lipid-containing and iron-containing lesions . Educational Goals/Teaching Points: The goals are to review the MR physics of T2* decay and demonstrate how lengthening of the time to echo (TE) can be used to identify regional field E236. A Pictorial Tour of Abdominal Manifestations in inhomogeneity caused by metal ion deposition, and present Neurocutaneous Syndromes (CME Credit Available) example cases including: quantitatively mild, moderate, and Shanbhogue, A.1,2; Fasih, N.1; Ojili, V.2; Surabhi, V.3; severe liver iron deposition (with pathology correlation), exam- Shanbhogue, D.2; Prasad, S.2; Khandelwal, A.4 1. The Ottawa ples of iron deposition in the liver, pancreas, and spleen resulting Hospital, Ottawa, Canada; 2. University of Texas Health Science from primary hemochromatosis, porphyria cutanea tarda, second- Center at San Antonio, San Antonio, TX; 3. University of Texas ary hemosiderosis, and cirrhosis alone, and an example of anoth- Health Sciences Center at Houston, Houston, TX; 4. Post Graduate er type of metal deposition in the liver (manganese) . Institute of Medical Education and Research, Chandiagrh, India. Address correspondence to A. Shanbhogue (shanbhogue_kp@ Key Anatomic/Physiologic Issues and Imaging Findings/ yahoo.com) Techniques: Iron deposition in the abdominal organs results in a progressively shortened T2* decay which is proportional to the Background Information: Neurocutaneous syndromes form a amount of iron deposited . This deposition can be measured quan- broad group of hereditary or congenital conditions which have titatively by performing a sequence with a progressively length- many features in common . They can present with a wide spec- ened TE . An automated calculation of the T2 slope can be per- trum of abdominal manifestations, ranging from benign inciden- formed for an image slice and a region of interest can be meas- tal findings to aggressive malignancies . Although these syn- ured . A lower T2 value in that region of interest indicates a greater dromes are relatively uncommon and often diagnosed clinically, amount of iron deposition, which can be correlated with histology . they can pose a diagnostic challenge and may lead to complica- tions which may occasionally be fatal . Radiology plays a pivotal Conclusion: MRI is able to diagnose and also quantify the degree role in the diagnosis when the classical clinical manifestations of iron deposition in the abdominal organs . Not only can MRI are not apparent, in the surveillance of clinically diagnosed assess iron deposition in hemochromatosis patients and patients patients and also can alert the clinician to the development of with iron overload, but the presence of iron deposition in the various unsuspected complications . abdominal organs in patients with cirrhosis is increasingly being recognized as clinically important and may require treatment . Educational Goals/Teaching Points: The goals are to describe the radiology of common and uncommon abdominal manifesta- tions of various neurocutaneous syndromes, and discuss the E235. Iron Containing Abdominal Pathologies: Exploiting the imaging features of various complications associated with them . Magnetic Susceptibility Artifact on MRI Morani, A.; Elsayes, K.; Liu, P.; Weadock, W.; Hussain, H.; Caoili, E. Key Anatomic/Physiologic Issues and Imaging Findings/ University of Michigan, Ann Arbor, MI Techniques: A comprehensive multimodality imaging review of Address correspondence to A. Morani ([email protected]) common and uncommon abdominal manifestations of tuberous sclerosis complex, neurofibromatosis, Sturge-Weber syndrome Background Information: A multitude of abdominal pathologic and Von Hippel-Lindau disease in the various organ systems entities such as hemochromatosis, siderotic liver nodules, gamna within the abdomen will be presented with emphasis on differ- gandy bodies, and hemorrhagic lesions, as well as paroxysmal ential diagnosis . Abdominal manifestations of tuberous sclerosis nocturnal hemoglobinuria etc . contain iron . These lesions drop including hepatic and renal angiomylipoma, renal cysts, renal cell signal on longer echo time (TE) MRI sequences due to T2* effect, cancer, retroperitoneal lymphangioma, and a variety of gastroin- called as magnetic susceptibility artifact . Magnetic susceptibility testinal tumors will be presented . Manifestations of Von Hippel and chemical shift artifacts can be used to diagnose iron and fat Lindau disease including pancreatic and renal cysts, renal cell containing lesions, respectively on MRI . cancer, pheochromocytoma, pancreatic serous cystadenoma,

255 El e c t r o n i c Ex h i b i t s : Gastrointestinal neuroendocrine tumors and adenocarcinoma of the pancreas will imaging findings in acute appendicitis, and review limitations of be described with attention to lesions that may undergo malig- the exam, and alternative diagnoses to consider in patients with nant transformation . Manifestations of neurofibromatosis and a similar clinical presentation . Sturge-Weber syndrome including various complications are also highlighted . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: MRI is often pursued at our institution if a pregnant Conclusion: Imaging of the abdomen in neurocutaneous syn- patient presents with right lower quadrant pain worrisome for dromes can be challenging given the wide spectrum and diverse acute appendicitis after a negative ultrasound or if suspicion is nature of involvement . Knowledge of the constellation of findings high . In a retrospective analysis, 50% of pregnant patients with specific to a syndrome helps in pinpointing the diagnosis . suspected appendicitis had positive findings on MRI . Of those Regular surveillance and follow-up guides in appropriate and patients that had surgery 80% had confirmed acute appendicitis timely management . on surgical pathology .

Conclusion: Diagnosing and appropriately managing a pregnant E237. Fat Containing Lesions of the Abdomen and Pelvis: CT patient with right lower quadrant pain can place one in a diagnos- and MRI tic dilemma . MR imaging sans intravenous contrast during preg- Jati, A. VA Boston Health Care System, West Roxbury, MA nancy has no known harmful effects on the fetus or mother, and Address correspondence to A. Jati ([email protected]) has been proven effective in the diagnosis of acute appendicitis .

Background Information: Demonstration of fat within the abdominal lesions can significantly narrow the differential diag- E239. Imaging Findings in Patients with Succinate nosis . CT and MRI can help identify macroscopic fat while MRI is Dehydrogenase Gene Mutations usually required to identify the microscopic fat . Bharwani, N.; Sahdev, A.; Rockall, A.; Srirangalingam, U.; Chew, S.; Reznek, R. Barts and The London NHS Trust, London, United Educational Goals/Teaching Points: The exhibit will outline the Kingdom importance of CT and MRI to identify microscopic and macro- Address correspondence to N. Bharwani (nishatbharwani@gmail. scopic fat in the various abdominal lesions; the major differential com) diagnosis on the basis of location and imaging findings, and fur- ther imaging or followup recommendations . Background Information: Mutations in genes encoding succi- nate dehydrogenase (SDH) are responsible for the majority of Key Anatomic/Physiologic Issues and Imaging Findings/ familial paragangliomas and also a significant proportion of “spo- Techniques: Fat containing abdominal lesions include congeni- radic” cases . Paragangliomas associated with SDH mutations tal, inflammatory, post-traumatic and neoplastic lesions . The ana- tend to occur in diverse anatomical locations and have a greater tomical location, imaging features and clinical history plays an potential for malignancy . Theories for tumorigenesis include important role in narrowing the differential diagnosis . These mitochondrial resistance to apoptosis and failure to inactivate lesions can contain macroscopic fat (lipoma, liposarcoma, angi- hypoxic inducible factors resulting in unsuppressed angiogenic omyolipoma, omental infarct, mesenteric panniculitis, epiploic stimulation . appendagitis, pseudolipoma, teratoma, pericaval fat, extramedul- lary hematopoiesis, and metastases) or intracellular lipid (focal Educational Goals/Teaching Points: The goals are for the steatosis, adenoma, focal nodular hyperplasia, regenerative nod- learner to be familiar with the range of appearances of paragang- ules, and hepatocellular carcinoma) . liomas in patients with SDH gene mutations and to understand how they differ from nonfamilial tumors and to appreciate Conclusion: CT and MRI lesions can help in characterization of diverse distribution of paragangliomas and potential for malig- fat containing abdominal lesions by allowing specific diagnosis or nancy associated with this mutation . narrowing the differential diagnosis . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The distribution of tumors and the various imaging E238. Right Lower Quadrant Pain in the Pregnant Patient: Is modalities that can be used in their detection will be discussed MRI Appropriate? and illustrated in this pictorial review . At our institution screening Ho, C.; Shin, K.; Carr, T.; Stay, R.; Lambert, D. University of of carriers is performed using MRI to avoid use of ionizing radia- Virginia, Charlottesville, VA tion . Lesions are typically high signal intensity on T2-weighted Address correspondence to C. Ho ([email protected]) imaging, a feature which is accentuated with the use of fat-sup- pressed sequences . The tumors are generally intermediate signal Background Information: Appendicitis is the most common intensity on T1-weighted imaging and enhance avidly with cause of the acute abdomen in pregnant female patients that administration of contrast . Functional imaging using meta-iodo- requires emergent surgical intervention . The purpose of this benzylguanidine and PET-CT can be used to detect metastatic exhibit will be to review normal gastrointestinal anatomy and the disease and help identify patients suitable for treatment with radiographic appearance of appendicitis on MRI in the pregnant radiopharmaceuticals . patient . Conclusion: This pictorial review describes the spectrum of dis- Educational Goals/Teaching Points: The goals are to review ease associated with SDH gene mutations and highlights the typ- MR techniques and sequences utilized in evaluation of suspected ical sites of paragangliomas and imaging features . appendicitis; review normal gastrointestinal anatomy, and MR

256 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E240. Lumps and Bumps of the Abdominal Wall: Cross- approach to diagnosis—an approach to the differential diagnosis Sectional Imaging Findings of gastrointestinal disease based on the MDCT reading of the Nagar, A.1; Katabathina, V.1; Prasad, S.1; Choudhary, S.1; Raut, bowel wall, localizing the segments involved, the extent of A.2; Chintapalli, K.1 1. University of Texas Health Science Center involvement, and associated mesenteric, nodal, and/or peritoneal at San Antonio, San Antonio, TX; 2. King Edward Memorial VII involvement, and the correlation with the clinical setting (drug Hospital, Mumbai, India treatment, time of onset, type and severity of symptoms, use of Address correspondence to A. Nagar ([email protected]) antibiotics, laboratory data) .

Background Information: Abdominal wall ‘lumps and bumps’ Key Anatomic/Physiologic Issues and Imaging Findings/ are commonly found in clinical practice and often present early Techniques: The disease categories described in this exhibit due to easy detection by the patients themselves . Common are: drug related inducing the mucosal barrier syndrome, its abdominal wall tumors include soft tissue desmoids, lipomas, pathophysiology and phases; neutropenic colitis (typhlitis); infec- neurofibromas, sarcomas, and hemangiomas . Most mesenchymal tious enterocolitis to include pseudomembranous colitis, bacteri- tumors of the abdominal wall show a wide spectrum of biologi- al, viral, and fungal etiologies; graft-versus-host disease and cal behavior with a high incidence of recurrence . Metastasis to spontaneous perforation . Correlation of the imaging findings to the abdominal wall is rare and commonly results from iatrogenic suggest a specific diagnosis or limited differential diagnosis will seeding of tumor . Rare primary tumors of the abdominal wall be discussed . include lymphoma, fibrous histiocytoma and peripheral nerve sheath tumors . A wide variety of abdominal wall non-neoplastic Conclusion: It is imperative that the radiologist be familiar with entities that mimic tumors include endometriosis, infections, her- and have an approach to the potential gastrointestinal complica- niations, and lesions arising from skin and its appendages like tions in the compromised patient . Due to the overlap of MDCT sebaceous cysts . Iatrogenic entities are being increasingly seen as findings of gastrointestinal inflammation an approach stressing a result of surgery or percutaneous interventions . the MDCT findings and correlating them with the clinical set- ting in which a disorder arises is essential in suggesting a specific Educational Goals/Teaching Points: The goals are to identify diagnosis or a limited differential diagnosis . and classify common tumors and pseudotumors of the abdomi- nal wall, and discuss the cross-sectional imaging findings of com- mon neoplastic and non-neoplastic lesions of the abdominal wall . E242. Spectrum of Stomach Pathology Demonstrated by MDCT McSweeney, M.; Siegel, S. Maine Medical Center, Portland, ME Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to M. McSweeney ([email protected]) Techniques: Cross-sectional imaging techniques, particularly CT helps in accurate detection, localization and characterization of Background Information: With the advent of thinner collima- abdominal wall tumors . MR is useful in tissue characterization of tion, negative oral contrast, and multiplanar reformats, MDCT has select abdominal wall lesions . Complications of iatrogenic nature improved the evaluation of gastric disease . Findings regarding the including hematoma, seroma, secondary infection, wall dehis- stomach on MDCT are often found incidentally . However, their cence, fistula formation are easily recognized using CT imaging . clinical relevance can be significant . Through prompt identification Secondary spread of the disease process into the peritoneum or of these abnormalities, appropriate follow-up studies can be rec- the extraperitoneal spaces are accurately assessed using CT . ommended . The purpose of this exhibit is to give an overview of Imaging findings dictate institution of appropriate management . the spectrum of stomach pathology that can be seen by MDCT .

Conclusion: In this exhibit, we discuss the cross-sectional imag- Educational Goals/Teaching Points: The goals are to provide a ing findings of the common tumors and pseudotumors of the pictorial review of primary and systemic entities that can affect abdominal wall . the stomach, as seen by MDCT, and increase the radiologist’s ability to recognize these findings . Increased detection will help the radiologist make appropriate follow-up recommendations, E241. MDCT of Gastrointestinal Complications Associated which will ultimately improve patient care . With a Compromised Host Oliphant, M.; Ott, D. Wake Forest University, Winston-Salem, NC Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to M. Oliphant ([email protected]) Techniques: This educational exhibit showcases a wide variety of pathologic abnormalities of the stomach as seen by MDCT Background Information: Recent advances in the treatment of through a didactic and image-rich format . Topics include, but are a variety of hematologic and nonhematologic diseases has lead not limited to benign and malignant gastric neoplasms, metastat- to potential cures . The morbidity related to treatment has ic disease to the stomach, inflammatory conditions such as gas- decreased, however, complications secondary to drug toxicity, tritis and peptic ulcer disease, portal gastropathy, stomach find- infections, and graft-versus-host disease persist . The new and ings in polyposis syndromes, stomach involvement in a systemic aggressive treatment modalities and their attendant morbidity vasculitis, and trauma to the stomach . Each case will be accom- and mortality make it essential that the radiologist be familiar panied by a detailed description of the image findings . with the potential complications . Conclusion: The advances in MDCT have improved the evalua- Educational Goals/Teaching Points: The MDCT appearance of tion of gastric disease . By viewing this exhibit, the radiologist will the various causes of gastrointestinal disease (for example, drug become familiar with the spectrum of stomach pathology that is related, neutropenic colitis, infectious enterocolitis, and graft-ver- seen by MDCT, ultimately leading to better patient care . sus-host) will be illustrated . The exhibit will offer a twofold

257 El e c t r o n i c Ex h i b i t s : Gastrointestinal

E243. Ride the Wave: Doppler Ultrasound Waveforms and Conclusion: Hernias of the abdomen and pelvis can be easily Their Essential Role in the Evaluation of the Abdominal identified with cross-sectional imaging . Often they are incidental Vasculature (CME Credit Available) findings but hernias can be the etiology of the patients symp- Stay, R.; Sarti, M. University of Virginia, Charlottesville, VA toms related to abdominal pain, obstruction and/or gastro- Address correspondence to R. Stay ([email protected]) esophageal reflux .

Background Information: Although a lot of information can be obtained from the patency and direction of flow of the abdomi- E245. A Vascular Road Map of Groin Hernias on MDCT nal vasculature, the Doppler waveforms also play a key role in Bayanati, H.; Abdeen, N.; Shabana, W. University of Ottawa, the evaluation of these vessels . The purpose of this exhibit is to Ottawa, Canada describe the normal and abnormal Doppler waveforms in the Address correspondence to H. Bayanati (hbayanati@hotmail. abdomen, with emphasis on the clinical relevance of each . com)

Educational Goals/Teaching Points: The goals are to provide Background Information: Groin hernias are the most common examples of normal and abnormal waveforms in several abdomi- type of hernias . These might be incidental findings, present with nal vessels including those of the liver, spleen, and kidneys, and complication or mimics other diseases . Clinical diagnosis of com- in liver and kidney transplants, and show such abnormal wave- plicated inguinal hernia can be difficult and due to the complex forms as tardus parvus, reversal of diastolic flow, dampened flow, anatomy of the groin, specific diagnosis of hernias in this region monophasic venous flow, turbulence, venous flow of transjugular on axial imaging can be challenging for an inexperienced observer . intrahepatic portosystemic shunt, pseudoaneurysm and arteriov- enous fistulous flow . Educational Goals/Teaching Points: In this exhibit we review the groin anatomy, and the different types of groin hernias . The Key Anatomic/Physiologic Issues and Imaging Findings/ diagnostic approach to inguinal hernia will be explained . The aim Techniques: Proper ultrasound technique, including correct use is to enhance the radiologists’ confidence to diagnosis, detection of the transducer frequency, gain, field of view, and Doppler of the type and any related complications of groin hernias . We angle, can help optimize visualization of the waveforms . Potential will provide a pictorial review of groin anatomy including the artifacts, including aliasing, incorrect Doppler gain, incorrect wall inguinal canal, femoral triangle as well as vascular landmarks filter, spurious spectral broadening, and vessel motion artifact, with a simple and easy algorithm for diagnostic approach . must be recognized . An abnormality within the Doppler wave- form may be the only clue to an underlying pathologic process . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Groin hernias are direct inguinal in 1/3 of the cases Conclusion: Every abdominal imager should have a thorough and indirect in 2/3 of the cases or femoral hernias . The latter are understanding of the varied Doppler waveforms of the abdomi- much less frequent, have a 10:1 female to male ratio and higher nal vasculature, as they are crucial in diagnosing many disease risk for incarceration (20-25%) compare to inguinal hernias processes . (3%) . The inferior epigastric artery (IEA) and femoral vein are important anatomic landmarks . If the hernia sac is located lateral the IEA, the hernia is indirect inguinal hernia . If the hernia sac is E244. Pictorial Review of Abdominal/Pelvic Hernias located medial to the IEA, and doesn’t compress on the femoral Simpson, W.; Lewis, S.; Aggerwal, A.; Rausch, D. Mount Sinai vein, the hernia is direct . If the femoral vein is compressed by the Medical Center, New York, NY hernia sac, a femoral hernia is present . Address correspondence to W. Simpson (william.simpson@ mountsinai.org) Conclusion: The vascular roadmap with an easy two-step algo- rithm using the IEA and the femoral vein provides a practical Background Information: To illustrate common and uncom- diagnostic approach to femoral and inguinal hernias . mon abdominal/pelvic hernias that can be encountered during routine cross-sectional imaging .

Educational Goals/Teaching Points: Abdominal/pelvic hernias can be an incidental finding or the cause of abdominal pain . Hernias can lead to bowel obstruction or other symptoms such as chest pain and gastroesophageal reflux .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The anatomy of the abdominal and pelvic cavities will be reviewed with attention to the location of hernias . In this pictorial essay we will describe various common hernias such as hiatal, inguinal and ventral . More unusual hernias will also be reviewed to include lumbar, obturator, trochar site, Spigelian and internal hernias as well as appendicitis in an inguinal hernia .

258 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

ovarian cancers . The role of MRI in staging ovarian cancer GU/Ob/Gy n remains a problem-solving modality . Sonography is excellent in detection of ovarian masses and ascites . However, it is limited in E246. Gastrointestinal Tract Involvement in Gynecological assessing peritoneal implants or abdominal lymphadenopathy . Disease The exhibit will discuss imaging pattern of primary ovarian cancer Balgude, A.; Samaroo, T.; Paspulati, R.; Pinchofsky, H. Case spread (local, peritoneal, lymph node, or heterogeneous dissemi- Western Reserve University, Solon, OH nation) and imaging of recurrent ovarian cancer (pelvic and/or Address correspondence to R. Paspulati ([email protected]) lymph node recurrence, peritoneal carcinomatosis, and other organ recurrence including very rare skeletal recurrence) . Objective: The objective is to discuss the gynecologic diseases Metastatic disease involving the ovary from other primary cancers that can involve the gastrointestinal (GI) tract, discuss the imag- may mimic primary or recurrent ovarian cancers . Some of the ing methods in evaluation of the GI tract in patients with gyneco- benign diseases with unusual imaging appearance may also logic disease, and to illustrate the various imaging findings of GI mimic primary or recurrent ovarian cancer, such as benign metas- tract involvement in gynecologic diseases . tasizing leiomyoma presenting with a pelvic mass, or endometri- osis presenting with abdominal and/or pelvic implants . Materials and Methods: This is a four-year review from 2004 to 2008 of all patients with various gynecologic diseases who had Conclusion: Some of the benign diseases with unusual imaging GI tract involvement on imaging . The imaging methods included appearance and metastatic disease involving the ovary from other barium enema, small bowel follow through, CT of the abdomen primary cancers may mimic primary or recurrent ovarian cancer and pelvis, PET imaging and MRI . Emphasis is made on cross- on imaging . It is important for the radiologist to make the correct sectional imaging with multiplanar reconstructions for demon- diagnoses so that appropriate treatment can be undertaken . stration of the GI tract in these patients .

Results: There were 57 patients in this study who had secondary E248. CT of the Adrenal Glands in Patients With Congenital GI tract involvement from a primary gynecologic disease . These Adrenal Hyperplasia: Correlation With Volume included benign entities such as endometriosis, pelvic inflamma- Measurements and Hormonal Profile (CME Credit tory disease, cervical, endometrial and ovarian cancer . The GI Available) tract involvement varied from serosal implants without and with Avila, N.1,2; Finkielstain, G.3; VanRyzin, C.4; Dwyer, A. 2; Williams, obstruction, strictures, fistulas and adhesions . D.2; Hanna, R.4; Thomas, F.2; Merke, D.3 1. Washington DC Veterans Affairs Medical Center, Washington, DC; 2. Warren G. Conclusion: GI tract involvement in gynecologic diseases is not Magnuson Clinical Center, Radiology and Imaging Sciences, uncommon and can be seen in both benign and malignant dis- National, Bethesda, MD; 3. Warren G. Magnuson Clinical Center, eases . Knowledge of the pathology and imaging features will Reproductive Biology and Medicine Branch, Bethesda, MD; 4. help the radiologist in choosing an appropriate imaging tech- Warren G. Magnuson Clinical Center, Bethesda, MD nique in arriving at a correct diagnosis . Address correspondence to N. Avila ([email protected])

Objective: The objective was to evaluate the CT findings in E247. Imaging Appearance of Primary and Recurrent patients with congenital adrenal hyperplasia (CAH) and correlate Ovarian Cancer and its Mimics them with volume measurements and levels of 17-hydroxypro- Ma, W.; Pandit-Taskar, N. Memorial Sloan Kettering Cancer gesterone (17-OHP) . Center,New York, NY Address correspondence to W. Ma ([email protected]) Materials and Methods: Twenty-three adult patients (20-57 years, mean 34 years) with CAH had nonenhanced and Background Information: This exhibit will describe radiological enhanced CT of the adrenal glands with 2 5. mm sections using staging of ovarian cancer: imaging findings and contribution of helical scanners . Adrenal enlargement was assessed from CT CT, MRI, ultrasound and PET-CT . It will illustrate imaging findings using established criteria that include: increased AP diameter, of primary and recurrent ovarian cancer and its mimics and dis- thickening, and increased length . Other CT features evaluated cuss the importance of differentiating primary ovarian or recur- included nodular appearance, and focal masses . Masses were rent ovarian cancers from other etiologies . determined to contain fatty elements if they contained material that measured less than -10 HU . Image processing was per- Educational Goals/Teaching Points: The goals are to familiar- formed using the CT images to obtain volume measurements of ize radiologists with primary and recurrent ovarian cancer: pat- the adrenal glands . The CT findings and volume measurements tern and spectrum of imaging findings, and their mimics such as were correlated with levels of 17-OHP, a biomarker commonly metastatic ovarian diseases, from other primary cancers, or some used to assess adrenal androgen control . benign etiologies; clues on imaging; sample cases and pitfalls . It is clinically important for the radiologist to correlate with clinical Results: Ten patients had normal adrenal glands by CT criteria; history, and consider differential diagnoses in order to make a volumes were 1 4-6. 8. cc, mean 3 8. cc; all had normal levels of correct diagnosis . Sometimes, biopsy is necessary when the 17-OHP . Nine patients had diffusely hypertrophied adrenal glands imaging findings of primary or recurrent ovarian cancer and its without nodularity; their volumes were 4 6-36. 2. cc, mean 10 .7 mimics are overlapping or confusing so that appropriate treat- cc; 4/9 had normal levels of 17-OHP and their volumes ranged ment can be undertaken . from 6 0-9. 1. cc, mean 7 6. cc; while 5/9 had elevated levels of 17-OHP and their volumes ranged from 4 6-36. .2 cc, mean 12 4. Key Anatomic/Physiologic Issues and Imaging Findings/ cc . Four patients had diffusely hypertrophied and nodular glands; Techniques: CT is the imaging modality of choice for staging their volumes were 12 7-32. 5. cc, mean 22 8. cc; 1/4 had normal 259 El e c t r o n i c Ex h i b i t s : GU/OB/GYN levels of 17-OHP and the volumes ranged from 12 .7-13 .1 cc, E250. The Postoperative Kidney: Interpreting Images After mean 12 9. cc; while 3/4 had elevated levels of 17-OHP and their Nephron-Sparing Renal Therapies (CME Credit Available) volumes ranged from 19 .5-32 .5 cc, mean 25 .3 cc . Three patients Allen, B.; Remer, E. Cleveland Clinic, Cleveland, OH had fatty adrenal masses; one had a 2 5. cm mass, no evidence Address correspondence to B. Allen ([email protected]) of hypertrophy, and normal 17-OHP; the second patient had had a 1 .5 mm fatty mass, hypertrophied and nodular glands, and ele- Background Information: The purpose of this exhibit is to vated 17-OHP; the third patient had six separate fatty masses in describe the procedural steps key to understanding nephron- the left adrenal gland that ranged from 0 .7-2 .5 cm, hypertrophied sparing renal therapies, including partial nephrectomy and renal and nodular glands, and elevated levels of OHP . tumor ablation, and to provide a pictorial review of normal and abnormal postprocedural imaging findings following nephron- Conclusion: Increased volume of the adrenal glands was associ- sparing renal therapies . ated with hypertrophy of the glands and elevated levels of 17-OHP . Volume measurements of the adrenal glands are useful Educational Goals/Teaching Points: Early postoperative imag- in the evaluation of patients with CAH and may be helpful during ing after partial nephrectomy is only obtained if a complication is follow-up to assess the efficacy of therapy . Three of 23 (13 %) of suspected . Complications after partial nephrectomy or ablation the patients had adrenal myelolipomas; the increased frequency include acute fluid collections such as abscess, hematoma, col- may relate to metaplasia of adrenocortical cells and chronic lecting system injury, or pseudoaneurysm . After partial nephrecto- adrenocorticotropic hormone elevation in patients with CAH . my, the intensity of follow-up is based on a risk-stratified approach, based on original tumor stage and other demographic factors . In some centers, baseline imaging is performed on the E249. Adrenal Masses: Imaging Characteristics (CME Credit day after tumor ablation, especially if contrast is not given during Available) the procedure . After tumor ablation, imaging should be per- Rekhtman, K.; Fawwaz, R.; Newhouse, J. Columbia University formed every 3-4 months during the first year . Medical Center, New York, NY Address correspondence to K. Rekhtman (katyarekhtman@yahoo. Key Anatomic/Physiologic Issues and Imaging Findings/ com) Techniques: In partial nephrectomy perinephric changes are common, but sometimes have unusual appearances, oxidized Background Information: Adrenal masses are identified in up to cellulose in the operative site may be mistaken for abscess, and 5% of CT scans . Characterization of these lesions is of great impor- recurrent disease is suspected with new enhancement at the tance, since adrenal glands are frequently involved in metastatic operative site . In tumor ablation ablated tumors are expected to and benign disease processes . There are numerous studies that decrease in size over time, to a greater degree after cryoablation characterize adrenal lesions with CT, MRI and PET imaging, than radiofrequency ablation, peripheral rim enhancement may attempting to differentiate benign from malignant imaging fea- be seen early and lesion growth and internal enhancement are tures . suspicious for tumor recurrence .

Educational Goals/Teaching Points: The optimal evaluation of Conclusion: Nephron-sparing therapies are common techniques the adrenal glands depends on the thorough understanding of in the treatment of low-stage renal tumors . Complications are the available imaging modalities and knowledge of the imaging rare, and imaging plays an important role in identifying these features that differentiate malignant from benign processes . complications and assessing for residual or recurrent disease . Imaging findings of normal adrenal and pathologic entities including adenoma, hemorrhage, cyst, hemangioma, histoplas- mosis, hyperplasia, lymphangioma, lymphoma, adrenal cortical E251. The Radiological Diagnosis and Treatment of cancer, myelolipoma, metastatic disease, neuroblastoma, pheo- Angiomyolipoma – An Update (CME Credit Available) chromocytoma, pseudotumor and oncocytoma will be addressed . Halpenny, D.; Snow, A.; McNeill, G.; Torreggiani, W. Adelaide + In addition, imaging algorithms for work-up of adrenal masses Meath Hospitals Incorporating the National Childrens Hospital, will be discussed . Dublin, Ireland Address correspondence to D. Halpenny (darraghhalpenny@hot- Key Anatomic/Physiologic Issues and Imaging Findings/ mail.com) Techniques: This educational exhibit will review the varied find- ings depicted on CT, MRI and PET in adrenal gland pathology . In Background Information: Angiomyolipoma (AML) is the most addition, state-of-the-art of imaging techniques for characteriza- common benign renal neoplasm . They cause significant morbidity tion of commonly encountered adrenal lesions will be reviewed . due to their ability to mimic neoplastic disease and their propen- sity to bleed . The classical imaging findings are well described, Conclusion: Following review of this exhibit, the viewer should but there have been several recent developments in both the be able to offer a broad differential for both common and diagnostic imaging of these tumors and in their radiologically- uncommon adrenal lesions; understand the imaging, pathologic based treatment . and clinical features of adrenal masses and discuss imaging algo- rithms for the work up of adrenal masses . Educational Goals/Teaching Points: The classical imaging find- ings will be briefly outlined . The most recent developments in the radiological diagnosis and treatment of AML will be discussed in detail .

260 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: Our experience suggests that renal embolization can Techniques: Regarding the use of MR, in phase/out of phase be easily, safely and successfully performed using microspheres, MRI using the India ink artifact has been recently used to accu- with limited postembolization toxicity . rately diagnose AML’s, while various sequences utilizing chemical shift (double-echo chemical shift FLASH ad chemical shift GRE) have demonstrated utility in differentiating minimal fat AML E253. Renal incidentalomas -The Unusual Suspects (CME from renal cell carcinoma (RCC) . Using CT sections of 1 5. mm Credit Available) are now able to characterize lesions <1 cm . The use of CT pixel Vummidi, D.1; Adamson, K.1; Bush, W.1; Lalani, T.2; Dighe, M.1 mapping is more accurate than conventional CT algorithms in 1. University of Washington School of Medicine, Kirkland, WA; 2. AML diagnosis and CT histogram analysis is more accurate than No Institutional Affiliation conventional methods for differentiation of AML from RCC . CT Address correspondence to D. Vummidi ([email protected]) angiography is now being used to noninvasively assess for aneu- rysm formation (a risk factor for bleeding) . Power Doppler Background Information: The advances in cross-sectional imag- increases the diagnostic accuracy of grey scale ultrasound in the ing have resulted in better spatial resolution and in the incidental assessment of small AMLs from 21% to 82 .4% and contrast-en- detection of smaller renal masses or incidentalomas . The proto- hanced ultrasound has shown initial promise in the assessment typical renal mass is the renal cell carcinoma . This exhibit is of AML . Several materials have demonstrated utility in AML devoted to the characterization of the other more unusual mass- embolization in both the acute and elective setting . Most recently es both neoplastic and inflammatory that can affect the kidney . the combination of particles and coils has allowed the effective embolization of both the vascular bed and the source vessel . Educational Goals/Teaching Points: The goals are to list the Radiofrequency ablation is a potential novel technique for elec- unusual neoplastic and non-neoplastic lesions that can affect the tive AML management . kidney; briefly describe the imaging technique necessary to pro- duce optimum multimodality images, and describe the character- Conclusion: AMLs represent an important diagnostic dilemma . istic imaging appearances of these lesions to enable an accurate The most recent developments in the imaging of AML should diagnosis . allow an accurate diagnosis in the majority of cases . The radiolo- gist should be at the forefront of the management of this disease . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The vast majority of renal masses are detected inci- dentally on ultrasound, CT and MRI due to either contour abnor- E252. Renal Embolization Utilizing Hydrophilic mality or abnormal echogenicity/enhancement/signal . The Microspheres–Experience in 50 Patients benign lesions are angiomolipoma, chronic hematoma, xan- Snow, A.; McNeill, G.; Halpenny, D.; Geoghegan, T.; Torreggiani, thogranulomatous pyelonephritis, perinephric abscess, and onco- W. Adelaide + Meath Hospital, Dublin, Ireland cytoma . The malignant lesions are transitional cell carcinoma, Address correspondence to A. Snow ([email protected]) liposarcoma, spindle cell carcinoma, squamous cell carcinoma, lymphoma and metastases . Their characteristic imaging appear- Objective: Renal embolization has become an increasingly com- ances will be depicted with histopathological, hematological and mon procedure over the last 30 years . Embolization coils have biochemical correlation where appropriate . traditionally been the material of choice when performing renal embolization . The purpose of this study is to determine whether Conclusion: The multimodality cross-sectional imaging appear- renal embolization with microspheres is a viable alternative with ances of unusual renal masses will be illustrated in this educa- potentially fewer side effects . tional exhibit . It is important for radiologists to be aware of their appearances to enable a confident diagnosis in the appropriate Materials and Methods: A total of 52 patients underwent renal clinical circumstances . The benefits include earlier treat- embolization using a combination of 700-900 µm and 900-1200 ment, reducing unnecessary surgical intervention, shorter hospital µm Embosphere microspheres over a period of four years . stays and alleviating patient anxiety . Twenty-six patients underwent embolization prior to elective nephrectomy for renal cell carcinoma (RCC) . Twenty-three patients underwent the procedure for palliation of the symptoms E254. Value of Quantitative and Qualitative MDCT Indices of metastatic RCC . We also performed embolization on two Differentiating Oncocytoma from Clear Cell Renal Cell patients with polycystic kidney disease (prior to elective nephrec- Carcinoma tomy) and one patient with renal trauma . Transfemoral aortogra- Bahrami, S.; Sauk, S.; Chow, D.; Raman, S. University of phy was performed in all cases, followed by selective renal angi- California, Los Angeles, Los Angeles, CA ography using a Cobra catheter . This was followed by flow-direct- Address correspondence to S. Bahrami (simin_bahrami@yahoo. ed selective injection of microspheres and a follow-up flush aor- com) togram to ensure occlusion . Objective: The goal is to characterize the differentiating imaging Results: No procedure-related complications were encountered . features of oncocytomas vs . clear cell renal cell carcinoma (RCC) . All patients who underwent renal embolization prior to nephrec- tomy for RCC subsequently underwent surgery successfully, with- Materials and Methods: Following IRB approval, query of the out the need for blood transfusion . Those patients who were department of pathology database identified 116 oncocytomas embolized due to symptomatic metastatic RCC obtained satisfac- and clear cell RCC in 105 consecutive patients who underwent tory palliation of their symptoms, with no patients in this group preoperative multiphasic single or multidetector helical CT scans requiring patient-controlled analgesia for longer than 24 hours over a seven year period . In consensus blinded readers character- postprocedure . ized lesion features including: shape (lobulated, smooth, irregu- 261 El e c t r o n i c Ex h i b i t s : GU/OB/GYN lar), hetero- or homogeneous enhancement, calcifications, exo- E256. Primary Retroperitoneal Masses: Radiologic- phytic growth pattern, size and maximal attenuation in the non- Pathologic Correlation (CME Credit Available) contrast (NC), corticomedullary (CM), nephrographic (N) and Choi, Y.; Kim, Y.; Jeong, W.; Cho, O.; Song, S. Hanyang University excretory phases (E) (0, 30-45 seconds, 65-85 seconds, and five Kuri Hospital, Kuri City, Kyunggido, South Korea minutes postcontrast, respectively) . Presence of enhancement of Address correspondence to Y. Kim ([email protected]) >100 HU was noted in the CM phase . Absolute and relative con- trast wash-out characteristics were calculated . Background Information: The retroperitoneum is the space behind the abdominal cavity without specific delineating anatom- Results: The majority of oncocytomas (20/24, 83%) had a ical structures . The retroperitoneal space contains the urinary sys- smooth shape while 49/92 (53%) clear cell were either lobulat- tem, greater vessels, uterus and part of gastrointestinal tract in ed or irregular, p=0 .006 . No oncocytoma was irregular in shape . adipose tissue . Masses arising in retroperitoneal space are rare A heterogeneous enhancement pattern was found significantly but include a broad spectrum of pathologic entities, including more often in clear cell RCC (83/92, 90%) than in oncocytomas benign and malignant, solid and cystic lesions . (15/24, 63%), p=0 .001 . Calcifications were present in 23/91 (25%) clear cell and 2/24 (8%) oncocytomas, p=0 .077 . The dif- Educational Goals/Teaching Points: The goals are that the ference in growth pattern and maximal enhancement in CM, N exhibit viewer will understand anatomy of retroperitoneal space, and E phases was not significantly different . More clear cell RCC and recognize the imaging findings that can be used to differenti- had enhancement >100 HU (80/92, 87%) than oncocytomas ate various retroperitoneal masses . (17/24, 71%), p=0 .057 . Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: Clear cell RCC were more likely to have lobulated Techniques: Retroperitoneal masses are classified into solid and contour and heterogeneous enhancement . The presence of calci- cystic mass . Cystic masses are divided into pure cystic mass and fication and enhancement >100HU was more common in clear cystic mass with nodular portion . Pure cystic retroperitoneal cell RCC than oncocytomas with a trend toward significance . masses include simple cyst, mucinous cystadenoma, and cystic Clear cell RCC and oncocytomas have significantly different clini- lymphangioma . Cystic masses with nodular portion include ter- cal prognosis . The ability to preoperatively distinguish oncocyto- atoma, endometrioma, and hematoma . Solid retroperitoneal ma from clear cell RCC can help improve patient care . masses are divided by vascularity into highly vascularized, inter- mediate vascularized and poorly vascularized masses . Highly vas- cularized retroperitoneal masses include extra-adrenal pheochro- E255. Nonvascular Renal Transplant Complications: It’s Not mocytoma . Intermediate vascularized retroperitoneal masses Always Colorful include leiomyosarcoma, malignant fibrous histiocytoma . Poorly Sayah, A.; Allison, S. Georgetown University Hospital, Washington, vascularized retroperitoneal tumor include ganglioneuroma, DC liposarcoma, idiopathic retroperitoneal fibrosis, lymphoma, meta- Address correspondence to A. Sayah ([email protected]) static lymph node .

Background Information: There is disproportionate emphasis Conclusion: Differential diagnoses of retroperitoneal mass still placed on vascular complications of renal transplantation . The remains a challenge, but certain specific findings are helpful for purpose of this activity is to review pathology found on the non- diagnosis, further treatment strategy and follow up . Doppler portion of a transplant study by exposing radiologists to a series of cases . E257. Uncommon Urinary Bladder Tumors; Different Imaging Educational Goals/Teaching Points: The goals are to discuss a Features for Urothelial Carcinoma variety of nonvascular complications of renal transplantation Kim, Y.; Jeong, W.; Cho, O.; Song, S.; Koh, B. Hanyang University including collections, parenchymal disease, as well as collecting Kuri Hospital, Kuri City, Kyunggido, South Korea system abnormalities; present ultrasound case images of various Address correspondence to Y. Kim ([email protected]) nonvascular renal transplant complications; emphasize the signif- icance of nonvascular renal transplant complications and to Background Information: The most common subtype of urinary stress that they should be addressed with each renal transplant bladder tumor, urothelial carcinoma, accounts for about 85% of evaluation . all bladder tumors . About 5% of bladder tumors are composed of nonepithelial tumor including mesenchymal origin tumor . Key Anatomic/Physiologic Issues and Imaging Findings/ Most bladder tumors have overlapping clinical symptoms wheth- Techniques: Cases will be presented in a quiz format . Key differ- er benign or malignant . It is critical that radiologists know about ential diagnostic points will be discussed with each case . The list discrete different imaging findings among various bladder of cases includes but is not limited to ultrasound images of calcu- tumors, including rarer subtypes and tumor mimicking lesions . li, pyonephrosis, collections, neoplasm, and ureteral stricture . Educational Goals/Teaching Points: This exhibit will provide an Conclusion: With emphasis routinely placed on evaluating understanding of the classification of bladder tumors and their for more common or dreaded vascular complications such as frequency, and characterize image features correlated with cysto- renal vein thrombosis and renal artery stenosis, non vascular scopic and pathological features . complications are frequently overlooked . The gray scale portion of the transplant study is often abbreviated . Complications dem- Key Anatomic/Physiologic Issues and Imaging Findings/ onstrated with gray scale imaging are significant and can be Techniques: We describe the characteristic features of rare forms detected, evaluated and followed with ultrasound . of bladder tumors with cystoscopic, pathological and imaging fea-

262 El e c t r o n i c Ex h i b i t s : GU/OB/GYN tures, including squamous cell carcinoma, adenocarcinoma, small E259. Beyond the “Usual” Pyelonephritis: Imaging of cell carcinoma of epithelial origin; leiomyoma of mesenchymal Uncommon Urinary Tract Infections and Their Mimics origin; metastasis or lymphoma as secondary involvement, and Shanbhogue, A.1,2; Fasih, N.1; McInnes, M.1; Prasad, S.2; Kielar, bladder tumor mimicking lesions such as actinomycosis . A.1; Shanbhogue, D.3 1. The Ottawa Hospital, Ottawa, Canada; 2. University of Texas Health Sciences Center at San Antonio, San Conclusion: Despite similar clinical features of bladder tumor, Antonio, TX; 3. No Institutional Affiliation some diseases have characteristic imaging findings and different Address correspondence to A. Shanbhogue (shanbhogue_kp@ growing patterns . According to tumor subtypes, treatment strate- yahoo.com) gy and prognosis is different . Characterization of variable tumors contributes to distinguishing each subtype, and affects the deci- Background Information: Urinary tract infection is the most sion on performing the next imaging technique and adequate common urologic disease affecting an estimate of 600,000 patient management . patients per year, the majority being uncomplicated and bacterial in origin . Only a small percentage of these are of interest to radi- E258. Virtual Cystoscopy Using : A New ologists with suspected pyelonephritis being the most common Dimension in the Evaluation of Urinary Bladder Pathologies indication for imaging in adults . Radiologists are well versed with Kantawala, K.; Dahiya, N.; Robinson, K.; Middleton, W.; Teefey, S. imaging of the usual bacterial pyelonephritis and associated Mallinckrodt Institute of Radiology, St. Louis, MO complications . Correlative clinical and laboratory evidence is also Address correspondence to K. Kantawala ([email protected]. helpful in diagnosing bacterial pyelonephritis . However, tubercu- edu) losis, fungal infections, hydatid cysts, emphysematous and xan- thogranulomatous pyelonephritis, infected renal cysts and a vari- Background Information: While 3D ultrasound (3D US) is com- ety of other urinary bladder and prostatic infections, albeit less monly used in prenatal imaging and screening, its use for clinical common, can pose diagnostic problems . A substantial number of applications beyond obstetrics is being increasingly explored . The noninfectious etiologies also mimic renal infections . purpose of this exhibit is to review the current role of 3D US using volume rendering parameters to look at the bladder lumen . Educational Goals/Teaching Points: The goals are to list the 3D US, virtual cystoscopy as it is commonly called, simulates the various urinary tract infections apart from the commonly encoun- endoluminal view seen in conventional cystoscopy and repre- tered pyelonephritis; identify the distinctive imaging features of sents a promising new approach for the noninvasive evaluation each of these relatively uncommon entities, and describe imag- of bladder pathologies . ing features that help differentiate them from various noninfec- tious causes that closely mimic them . Educational Goals/Teaching Points: At the end of this presen- tation, the viewer will be familiar with 1) the basic physics and Key Anatomic/Physiologic Issues and Imaging Findings/ technique of acquiring 3D US images of the bladder and, 2) the Techniques: In this exhibit, we will present imaging of various 3D US imaging features of common bladder pathologies . urinary tract infections including renal tuberculosis, hydatid cyst, fungal infections, a spectrum of emphysematous infections and Key Anatomic/Physiologic Issues and Imaging Findings/ xanthogranulomatous pyelonephritis, infected renal cysts and var- Techniques: 3D US virtual cystoscopy provides an endoluminal ious vesical and prostatic infections . Imaging of their mimics image of the urinary bladder without using endoscopy, ionizing including but not limited to lymphoma, renal cell cancer, urothe- radiation or contrast media . This exhibit will illustrate the basic lial malignancy, renal necrosis and graft-versus-host disease will physics and technique of acquiring 3D US images of the bladder . also be presented . Salient features of these entities will be Various rendering parameters available for postprocessing will be described which will facilitate reliable and accurate diagnosis . reviewed . 3D images of several pathologically proven lesions will be shown, including, but not limited to: 1) bladder tumors, Conclusion: Uncommon types of urinary infections should be including transitional cell cancer, 2) bladder diverticula, 3) blad- kept in mind in imaging evaluation of the urinary tract . der calculi, 4) endometriotic deposits in bladder wall and 5) cys- Knowledge of the various noninfectious mimics is essential to titis . The role of 3D US as a problem solving tool in detecting and avoid misdiagnosis and implement timely management . characterizing bladder lesions will be discussed . Artifacts and pit- falls exclusive to 3D US will also be covered . E260. Urolithiasis: Imaging Essentials and What the Conclusion: 3D ultrasound by virtue of its volume rendering Urologist Wants to Know (CME Credit Available) capabilities, facilitates visualization of the urinary bladder lumen Moin, P.; Dunn, M.; Boswell, W.; Duddalwar, V. University of in a manner closely simulating conventional cystoscopy . Virtual Southern California, Glendale, CA cystoscopy using perspective, volume rendered, 3D data repre- Address correspondence to P. Moin ([email protected]) sents a promising new approach for the noninvasive evaluation of bladder pathologies . Background Information: Urolithiasis is a relatively common entity and can have several different clinical and imaging mani- festations . Identification, evaluation and reporting of urolithiasis and its potential complications are important subjects for the diagnostic radiologist to be familiar with both due to its preva- lence and the need to effectively communicate findings to the treating urologist .

263 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

Educational Goals/Teaching Points: This presentation aims to imaging, can help define malignant lesions . These examples will present an overview of the etiologies of urolithiasis; review imag- be correlated with pathology results . ing findings of urolithiasis and its secondary effects, primarily on noncontrast-enhanced CT; suggest a standard format for the Conclusion: Accurate local staging of prostate cancer is possible reporting of urolithiasis to facilitate relevant and clear communi- using surface body coils and a 1 .5T magnet . In addition, it is pos- cation of findings, and highlight relevant findings which are sible to perform advanced imaging techniques, such as DWI and important for the urologist to know in order to decide upon fur- MRS of the prostate at the same time, without the use of an ther management . endorectal coil . This has the potential to allow more wide-spread use of MR imaging of prostate cancer, availing tumor localization Key Anatomic/Physiologic Issues and Imaging Findings/ and staging information to referring urologists and radiation Techniques: With urologist collaboration, this presentation will oncologists . This information can be used in treatment planning, include relevant anatomy, including surgical anatomy; a review of and hence can result in improved patient care . findings and their significance; differentiation of types of calculi as suggested by imaging findings, and review of treatment options and factors that determine treatment choice . E262. Evaluation of Dynamic Contrast-Enhanced MRI for Detection of Bone Metastasis in Patients With Prostate Conclusion: It is hoped that this multidisciplinary effort with pro- Cancer vide an effective review of the imaging findings of urolithiasis Oto, A.; Kulkarni, K.; Yang, C.; Karczmar, G.; Stadler, W. University and its complications, an education and reference tool for radiol- of Chicago, Chicago, IL ogists to report findings in a clinically relevant manner to facili- Address correspondence to A. Oto ([email protected]. tate the determination of appropriate treatment options, and a edu) foundation for further endeavors to standardize the reporting of urolithiasis . Objective: The objective is to evaluate the role of dynamic con- trast-enhanced (DCE) MRI in detection of bone metastasis in patients with prostate cancer . E261. Prostate Imaging at 1.5T With Surface Body Coils: Feasibility of Technique With Potential Widespread Use to Materials and Methods: Sixteen prostate cancer patients with Stage Prostate Cancer proven bone metastasis (median age 65, ranges from 49 to 64), Sarwani, N.; Tappouni, R.; Pagano, M. Penn State Milton Hershey were included in the study . T1-weighted axial images were Medical Center, Hummelstown, PA obtained through the bone metastases and normal bones were Address correspondence to N. Sarwani (doctor@nabeelsarwani. obtained at two second resolution for one minute before and com) seven minutes after bolus injection of 0 1. mmol/kg gadodi- amide . 2D fast spoiled gradient-echo pulse sequence with TR/TE Background Information: Accurate staging of prostate cancer is =7 .8/1 .7 milliseconds, flip angle 60° was used . The regions of important for deciding treatment options, as well as to predict interest were placed over bone metastases, normal bone and prognosis . Also accurate localization of prostate cancer is muscles by an experienced radiologist . Using a multiple refer- now being used in novel approaches for targeted radiation thera- ence tissue method, the contrast agent arterial input function py treatment planning . A review of the radiology literature reveals was estimated and used to calculate contrast agent transfer rate the majority of prostate MR imaging involve the use of endorec- Ktrans (volume transfer constant between blood plasma and the tal coils, with the current trend to use 3T magnets . Such require- extravascular extracellular space (EES)), and Ve (the fractional ments may deter prostate imaging from being performed on a volume of EES) applying the Tofts model . Kinetic perfusion wide spread basis . We demonstrate the feasibility to perform parameters of normal and abnormal bone were compared using accurate prostate MR imaging at 1 .5T, including advanced imag- student t-test . ing techniques such as diffusion-weighted imaging (DWI) and MR spectroscopy (MRS), using surface body coils only . Results: All bone metastases showed significant enhancement, with median Ktrans=0 .079 minute-1 (range from 0 028. to 0 .319, Educational Goals/Teaching Points: The goals are to review mean 0 .100) and median Ve=0 136. (range from 0 055. to 0 .234, the zonal anatomy of the prostate using surface body coils in a mean 0 .133) . In normal bones, 12 patients showed slightly nega- 1 5T. magnet; delineate prostate cancer staging on MR including tive enhancement which might be due to T2* effect . Three capsular invasion, neurovascular spread, as well as local invasion; patients showed statistically insignificant and negligible enhance- demonstrate the technical feasibility of performing DWI and MRS ment with Ktrans less than 0 008. minute-1; only one patient of the prostate, using surface body coils in a 1 .5T magnet, and showed strong enhancement in normal bones, with Ktrans 0 .080 describe the advantages and disadvantages of DWI and MRS in and Ve 0 0477. . Student t-test showed that both Ktrans and Ve prostate cancer . were significantly larger in bone metastases than in normal bones . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The presentation will be an auto-tutorial, with all Conclusion: DCE-MRI can easily distinguish prostate cancer cases showing prostate MR images obtained using only surface metastases from normal bone marrow . Decreased or lack of nor- body coils . Imaging findings of the various stages of prostate can- mal bone marrow enhancement in the elderly patients facilitates cer will be shown . Examples will be shown demonstrating the the detection of bone metastasis from prostate cancer . Our effective role of DWI as a tool to aid in prostate cancer localiza- results also suggest that pulse sequences that separate T1 and tion . Similarly, MRS will also be shown, and how the altered cit- T2* effects of contrast media may improve sensitivity and specifi- rate/choline ratio, when combined with conventional prostate city for detection of bone metastasis .

264 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

E263. 3D Doppler Sonography and Dynamic Contrast- of Health) . After surgery, all prostates were examined by patholo- Enhanced MRI of Recurrent Prostate Cancer Following High gists . Postoperative tumor volumes were calculated from patho- Intensity Focused Ultrasound Therapy logical sections of the prostates . Tumor volumes calculated from Bard, R.1; Barentsz, J.2 1. Biofoundation for Angiogenesis the preoperative MRIs and the postoperative pathological meas- Research and Development, New York, NY; 2. UMC St. Raboud, urements were statistically analyzed using a Student’s t-test . Nijmegen, Netherlands Address correspondence to R. Bard ([email protected]) Results: Lesion Locations and Numbers: In 18 of the 29 patients up to small five lesions were not detected by MRI, Objective: The goal is to compare the value of 3D power because the MRI resolution was not sufficient enough . Doppler sonography (3D-PDS) with dynamic contrast-enhanced Additional discrepancies were seen in lesions in the inner (DCE)-MRI in the evaluation of prostate cancer recurrence follow- gland (8/18) and lesions masked by postbiopsy changes (4/18) . ing high intensity focused ultrasound (HIFU) treatment . In a correlative review with pathology, time to signal-intensity curves and DCE-MRI parameter color maps were helpful to Materials and Methods: Seventy-nine patients with prostate detect additional small lesions in seven cases . DCE-MRI helped cancer treated by HIFU were prospectively scanned with an 18 to delineate lesions in the inner gland in three of eight patients MHz endorectal probe (GE Healthcare, Milwaukee, WI) with and in one of four patients with postbiopsy changes . Tumor power Doppler image reconstruction . All patients were scanned Volumes: Preoperative MR estimations (20 8. ± 16 .3) ml and within one week with a 1 .5T MRI using large field T1-weighted postoperative pathologic findings (16 .6 ± 12 .9) ml were signifi- images and axial, sagittal and coronal small field T2-weighted cantly different (p<0 .01) . images and DCE-MRI evaluation in the axial plane with compu- ter-assisted time point software . Eighteen patients with Gleason Conclusion: Radiological–pathological correlation of prostate 4 or 5 disease had biochemical recurrence within six months and cancer reveals limitations of standard MRI sequences and pro- were reimaged by 3D-PDS and DCE-MRI . No patients with vides a roadmap for the development of advanced MRI tech- Gleason 3 disease had PSA elevations in that time frame . niques for prostate cancer . Small lesions and lesions in the inner gland are often not detected even with high-field MRI . Tumor vol- Results: Four of 18 recurrences were correctly imaged by stand- umes measured on T2-weighted images are often underestimat- ard MRI . This is expected due to the signal irregularity caused by ed . Therefore, DCE-MRI might have the potential to better deline- HIFU tissue ablation . Sixteen of 18 tumors were imaged by ate lesions in the prostate and to improve volume measurement 3D-PDS and 16/18 were imaged by DCE-MRI . 3D-PDS correla- of prostate cancer with parameter color maps . Quantitative tion with DCE-MRI was strong with two patients missed by each approaches in DCE-MRI can help to improve the radiological modality . diagnosis of prostate cancer especially for small lesions and lesions in the inner gland . Conclusion: Noncontrast MRI and gray scale sonography are not accurate in detecting tumor recurrence in the thermally ablated prostate . 3D-PDS and DCE-MRI appear equally sensitive in detec- E265. Correlation of Dynamic Contrast-Enhanced MR tion of cancer regrowth and offer the possibility of image-guided Imaging with Histopathological Tumor Grade in Prostate biopsy and treatment . Cancer: Percent Enhancement a Novel Technique McClure, T.; Margolis, D.; Gomez, A.; Raman, S. University of California, Los Angeles, Los Angeles, CA E264. 3T MRI of Prostate Cancer without an Endorectal Coil: Address correspondence to T. McClure ([email protected]. A Radiological-Pathological Correlation (CME Credit edu) Available) Sammet, S.; Takayama, Y.; Jia, G.; Wang, W.; Shah, Z.; Dangle, P.; Objective: The objective is to determine whether strength of Jimenez, R.; Patel, V.; Knopp, M. The Ohio State University, enhancement on DCE-MR can predict the grade of prostate Columbus, OH cancer . Address correspondence to S. Sammet ([email protected]) Materials and Methods: IRB approval was obtained prior to Objective: The purpose of this study was to correlate preopera- this study . On a 1 .5T magnet with endorectal coil, dynamic con- tive 3T MR imaging of prostate cancer with postoperative patho- trast-enhanced imaging was performed in 23 men with biopsy logical results . Discrepant cases and mismatched lesions were proven prostate cancer that then underwent radical prostatecto- retrospectively analyzed to determine the best imaging sequenc- my . The percent peak enhancement was calculated . The region of es for the detection of prostate cancer in-vivo at 3T . highest tumor grade identified at pathology was then localized on MR and compared to contralateral normal prostate tissue Materials and Methods: Twenty-nine patients (age=46-72 using paired student’s t-test . These patients were further stratified years, mean=57 .9 years, average PSA=7 .1 ng/ml, average Gleason into either Gleason score= 6 or Gleason score >6 . score=7) with biopsy-proven prostate cancer were scanned on a 3T MR system (Philips Healthcare, Cleveland, OH) in an 8-chan- Results: Of the 23 patients evaluated the average value of nel phased-array coil before surgery . Lesion locations and num- enhancement in the region of prostate cancer was 355%, where- bers were assessed on T2-weighted, dynamic contrast-enhanced- as normal prostate cancer was 139% (p<0 .001) . When compar- MRI (DCE-MRI) and ADC maps . DCE-MRI was quantitatively ana- ing low-grade vs . higher grade prostate cancer the average value lyzed with in-house software . Preoperative tumor volumes were of percent enhancement for low-grade disease was 337% and measured from axial T2-weighted using medical image process- 384% for higher grade disease (p=0 .03) . ing, analysis and visualization (released by the National Institutes

265 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

Conclusion: Clinical preoperative diagnostic tools are limited in cer as defined by current state-of-art imaging techniques includ- assessing tumor grade, yet tumor grade determines management ing CT, MR and bone , and to understand pathways in prostate cancer . On DCE-MRI the maximal percent peak and patterns of disease spread . The exhibit will demonstrate typ- enhancement correlates with highest tumor grade in prostatic ical and atypical manifestation of disease and discuss the role of adenocarcinoma . DCE-MRI may noninvasively help determine state-of-art imaging techniques on patient management and highest tumor grade . treatment decision .

Key Anatomic/Physiologic Issues and Imaging Findings/ E266. Dynamic Contrast-Enhanced MR Imaging of Prostate Techniques: This exhibit will illustrate the spectrum of prostate Adenocarcinoma: Novel Application of Wash-In and Wash- cancer as defined by state-of-art imaging modalities including the Out Maps–Indicators of High-Grade Disease appearance of primary tumor, local staging, pathways of the loco- McClure, T.; Margolis, D.; Gomez, A.; Raman, S. University of regional and lymphatic spread, as well as distant metastases . California, Los Angeles, Los Angeles, CA Both typical and atypical disease presentation will be discussed . Address correspondence to T. McClure ([email protected]. The limitations and pitfalls of these imaging modalities will also edu) be addressed . Finally, the roles of these state-of-art multimodality imaging techniques on patient management decision will be Objective: The objective was to evaluate dynamic contrast-en- carefully defined based on different therapeutic options . hanced MRI wash-in and wash-out for the discrimination of low- grade vs . high-grade cancer . Conclusion: This exhibit will comprehensively review the radio- logic spectrum of prostate cancer in all stages with emphasis on Materials and Methods: On a 1 5T. magnet with endorectal coil, pathways and patterns of disease spread . Understanding of typi- dynamic contrast-enhanced imaging was performed in 23 men cal and atypical prostate cancer may facilitate better detection of with prostate cancer who underwent radical prostatectomy . disease, accurate diagnosis and optimal treatment . Contrast wash-in and wash-out color maps were generated on a dedicated workstation . The region of highest tumor grade identi- fied on pathology was then localized on MR and compared to E268. Prostate Cancer Imaging: What, Why, and When contralateral normal prostate tissue using paired student’s t-test . (CME Credit Available) These patients were further stratified into either Gleason score= Garcia Figueiras, R.1; Vilanova, J.2; Patel, S.3; Gómez Caamaño, 6 or Gleason score >6 . A.1; Baleato González, S.4; Villalba Martin, C.1; Bermúdez, A.1; Padhani, A.3 1. Complexo Hospitalario Universitario de Santiago Results: Focal areas of high wash-in were conspicuous in seven de Compostela, Santiago De Compostela, Spain; 2. RM Clínica of 14 patients with Gleason score 6 prostate cancer patients and Girona, Girona, Spain; 3. Paul Strickland Scanner Centre, eight of nine patients with higher grade disease . This approached Northwood, Middlesex, United Kingdom; 4. Complexo statistical significance (p=0 .086) . The difference between Hospitalario de Pontevedra, Pontevedra, Spain Gleason score 6 and higher-grade tumors’ wash-out was signifi- Address correspondence to R. Garcia Figueiras (roberto.garcia. cant (p=0 .028) . [email protected])

Conclusion: Clinical preoperative diagnostic tools are limited in Background Information: Appropriate imaging for prostate can- assessing tumor grade, yet tumor grade determines management cer (PC) patients depends on clinical situation and disease state . in prostate cancer . On DCE-MRI wash-out correlates with highest Actually, no consensus exists regarding the use of imaging for tumor grade . DCE-MRI may noninvasively help determine highest evaluating PC . Improvements in PC diagnosis and treatment will tumor grade . Thus, these techniques may be used to stratify depend on new imaging modalities such as functional imaging patients with in situ prostate cancer . techniques .

Educational Goals/Teaching Points: The goals are to describe E267. State-of-Art Imaging Approach to the Prostate Cancer: the role of different imaging methods in diagnosis, cancer locali- Special Emphasis on the Pattern of Locoregional and zation, staging, treatment planning, evaluation of tumoral Distant Metastasis (CME Credit Available) response, and follow-up in PC; introduce the emerging role of Lee, J.; Dighe, M.; Bush, W. University of Washington, Seattle, WA functional imaging in PC; discuss the functional anatomy of the Address correspondence to J. Lee ([email protected]) prostate and periprostatic area; present the possible role of com- puter-aided diagnosis (CAD) software in prostate imaging; Background Information: Prostate cancer is the second most present the utility of fusion processing tools for joint analysis of common cause of cancer-related death in men . Since more than conventional and functional images, and discuss imaging guide- 25,000 men die of distant metastasis per year, multimodality lines in different clinical situations: detection of suspected PC, imaging including state-of-art CT, MR and plays staging, and surveillance . a major diagnostic role in detecting and defining the extent of disease . The prognosis and management decisions are based on Key Anatomic/Physiologic Issues and Imaging Findings/ the knowledge of true extent of disease . Therefore, the accurate Techniques: Relevant imaging findings are shown with different staging is crucial in determining and planning surgical respecta- imaging techniques: transrectal ultrasonography (US), dynamic bility as well as detecting recurrent or persistent disease . contrast-enhanced US, , CT, MR imaging techniques, such as diffusion-weighted imaging (DWI), dynamic contrast-en- Educational Goals/Teaching Points: The goals are for the view- hanced MRI, MR spectroscopy (MRS), and MR-lymphography, er of the exhibit to learn radiographic spectrum of prostate can- radionuclide bone scanning, and PET-CT . The key points in PC

266 El e c t r o n i c Ex h i b i t s : GU/OB/GYN imaging with these techniques are discussed, including detection area at the level of the L3-L4 intervertebral disc . The technique of small cancer foci; central gland tumors; T2 vs . T3 patients; N+ used for fat tissue measurements in CT cross-sectional images patients; metastatic disease, and treatment planning and tumoral has been previously standardized and validated . An age matched response evaluation . control group was recruited from patients referred for a CT scan to investigate abdominal pain . Conclusion: The synthesis of anatomic, functional, and molecu- lar imaging techniques will be the key point in the management Results: Thirty patients with a mean age of 62, and 30 control of patients with prostate cancer . Improvements in PC diagnosis patients were retrospectively assessed . Patients with endometrial and treatment depend on improved imaging, mainly functional cancer had significantly higher VAT area than the control group imaging techniques . Advanced functional tools will enable us to (130 vs . 57 cm2; p<0 .01) . They also had a significantly higher detect earlier stages of PC, identify poor prognosis tumors, detect SAT area than the control group (265 vs . 145 cm2; p<0 .01) . central gland tumors, and guide focal therapies . There is however no significant increase in the ratio of VAT to total adipose tissue (0 33. vs . 0 28). in patients with endometrial cancer . We also found the VAT area was significantly higher in the E270. Sonography of Unusual Benign Intratesticular Masses patients presenting with late stage disease (stage 3 and 4), than (CME Credit Available) in the control group (187 vs . 57 cm2) or the patients with early Huang, B.; Bhatt, S.; Dogra, V. University of Rochester Medical stage disease (187 vs . 122cm2) . Center, Rochester, NY Address correspondence to B. Huang (brady_huang@urmc. Conclusion: Obesity is associated with an increased risk of rochester.edu) endometrial cancer . Both subcutaneous and visceral adipose tis- sue is increased in patients with endometrial cancer . Visceral adi- Background Information: The purpose of this exhibit is to pose tissue is increased in patients presenting with late stage dis- describe the sonographic features of uncommon and common ease compared to patients with early stage . This has possible benign intratesticular pathologies . Some of these will include implications for disease prognosis and future treatment options . congenital adrenal rests, hamartomas, splenogonadal fusion, tuberculous gummas, vascular lesions, fibrous pseudotumor, sar- coidosis, postradiation fibrosis, and spontaneous intratesticular E272. The Many Faces of Endometriosis, Typical and Atypical hemorrhage . Other common entities such as epidermoids and Findings. CT, Ultrasound and MRI with Pathological benign cystic lesions will also be reviewed . Correlation: A Pictorial Essay Onyiuke, I.; Scoutt, L.; McCarthy, S. Yale University Hospital, New Educational Goals/Teaching Points: The goals are to review Haven, CT the clinical and sonographic features of unusual benign intrates- Address correspondence to I. Onyiuke ([email protected]) ticular entities and more commonly encountered benign lesions, and understand some features that may help distinguish true tes- Background Information: Endometriosis is the presence of ticular neoplasms from benign tumor-like entities . ectopic functioning within the peritoneal cavity . While this is a common disease, symptoms may be nonspecific and associated Key Anatomic/Physiologic Issues and Imaging Findings/ with considerable morbidity, including pain and infertility . Techniques: After viewing the exhibit, the learner will under- stand the normal sonographic appearance and anatomy of the Educational Goals/Teaching Points: Though the common testes . imaging findings in endometriosis are well known, there are a variety of atypical findings which can mislead the radiologist on Conclusion: Unusual testicular pathologies are uncommon, but ultrasound, CT and MR . Typical locations in the pelvis around the may be encountered in clinical practice . Familiarity with these ovaries and uterus are easy to diagnose but atypical locations like entities and their clinical presentations may help to avoid more the rectovaginal septum and caesarian section scar can be more invasive interventions . challenging .

Key Anatomic/Physiologic Issues and Imaging Findings/ E271. CT Assessment of the Abdominal Fat Distribution in Techniques: Ultrasound, the most easily accessible screening Endometrial Cancer tool is limited because endometriosis is often nonspecific on Knox, M.; Beddy, P.; Murphy, G.; McMahon, C.; Keogan, M. St. ultrasound . Adhesions and implants on bowel and peritoneal James’s Hospital, Dublin, Ireland surfaces may be missed . CT, which may be the first imaging Address correspondence to M. William ([email protected]) test performed in women who present with abdominal or pelvic pain lacks pathognomic features . MRI is more sensitive and spe- Objective: The risk of endometrial cancer is 2-3 times higher in cific for atypical manifestations of endometriosis such as glandu- overweight and obese women . Obesity also adversely affects sur- lar endometriosis, adhesions, muscular involvement as well as vival in most studies . The aim of this study was to assess the fat complications like rupture and malignant degeneration . distribution in patients with a new diagnosis of endometrial cancer . Conclusion: While ultrasound and CT may exhibit nonspecific Materials and Methods: Patients with a histologically confirmed findings, it is important to recognize these to guide the clinician diagnosis of endometrial cancer were included . The visceral adi- to obtain an MRI which is a more definite test . MRI should then pose tissue (VAT) and subcutaneous adipose tissue (SAT) were be carefully reviewed for the more atypical presentations of this calculated from the patient’s initial staging CT scan . The VAT and fairly common disease . SAT were calculated by measuring their respective cross-sectional

267 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

E273. Recent Imaging and Interpretation Advances in or a mass such as a dermoid without specific evidence for tor- Diagnostic Workup of Ovarian Cystic Lesions (CME Credit sion, to a highly specific appearance with multiple peripheral fol- Available) licles in an enlarged ovary with a twisted appearance of the asso- Wasnik, A.1; Elsayes, K.1; Caoili, E.1; Platt, J.1; Menias, C.2 1. ciated adnexal structures and edema of the adjacent fat . In cer- University of Michigan Hospital, Ann Arbor, MI; 2. Mallinckrodt tain cases the CT findings are all that are needed prior to opera- Institute of Radiology, St. Louis, MO tive intervention, whereas in other cases emergent sonographic Address correspondence to A. Wasnik ([email protected]) correlation is very helpful for confirmation . The goals of this exhibit are to educate the radiologist as to this spectrum as well Background Information: The diagnosis of ovarian cystic as to review the current CT, ultrasound, MR, and clinical literature lesions continues to represent a daily challenge despite the on ovarian torsion . recent advances in cross-sectional imaging . Different diagnostic algorithms in pre and postmenopausal females have been devel- Key Anatomic/Physiologic Issues and Imaging Findings/ oped over the past decade . These algorithms however, need to Techniques: Multiple CT examples will be shown from our prac- be modified according to recent trends in interpretation of imag- tice, including simple cysts which led to torsion; torsion without es particularly on MRI, with its current spectrum of pulse an underlying lesion (typically in perimenarchal girls); ovarian sequences . Particular imaging findings are used to differentiate dermoids with and without specific evidence for associated tor- benign from malignant lesions . We found, however, that radiolo- sion; noncontrast CT of ovarian torsion; and ovarian lesions such gists need to be more familiar with some lesions which can be as cystadenomas in middle-aged to older women which present- quite confusing . For instance, cystadenofibroma which can be ed with torsion . Correlative sonographic imaging studies will be seen as complex ovarian predominantly cystic lesion is often shown, and pitfalls will be discussed, e .g . cases with preservation diagnosed as malignant despite its benign nature . of ovarian flow on sonography despite other findings of torsion on CT . Educational Goals/Teaching Points: The goal is to discuss the current diagnostic work up of ovarian cystic lesions . Special Conclusion: The radiologist should recognize the spectrum of emphasis will be placed on problem solving pathways and inter- appearances of ovarian torsion on CT, as the diagnosis may be pretation advances of ovarian cystic lesions . Diagnostic algo- established prospectively in girls and women imaged without an rithms will be discussed and suggested . initial clinical suspicion for this specific diagnosis .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The exhibit begins with an introduction on tech- E275. Solid Ovarian Masses: Cross-Sectional Imaging With niques and various modalities used for evaluation of ovarian cyst- Emphasis on MRI ic lesions . Spectrum of imaging features of these lesions will be Shanbhogue, A.1,2; Fasih, N.1; Ojili, V.2; McInnes, M.1; illustrated . Representative examples of each entity will be pre- Shanbhogue, D.2; Prasad, S.2 1. The Ottawa Hospital, Ottawa, sented . Canada; 2. University of Texas Health Science Center at San Antonio, San Antonio, TX Conclusion: Ovarian cystic lesions are a commonly encountered Address correspondence to A. Shanbhogue (shanbhogue_kp@ entity on imaging . Diagnostic algorithm and utility of various yahoo.com) imaging modalities, with knowledge of the interpretation and familiarity of the radiologist to these lesions are of paramount Background Information: The majority of the ovarian masses significance in differentiating benign from malignant lesions . (>60%) are epithelial in origin and cystic . Solid masses form only a small subset . Time and again, radiologists focus on cystic ovari- an masses with emphasis on early diagnosis of ovarian malig- E274. Ovarian Torsion: CT Diagnosis in Children and Adults nancy which is well justified . However, solid ovarian masses, Saxon, P.; Luongo, J.; Badler, R.; Katz, D. Winthrop-University albeit less commonly encountered, can cause serious and some- Hospital, Mineola, NY times life-threatening complications . Although diagnosis can be Address correspondence to D. Katz ([email protected]) fairly straight forward in some cases, it can be more challenging when unusual presentations and complications are encountered . Background Information: Ovarian torsion is occasionally identi- The purpose of this exhibit is to describe the imaging spectrum fied prospectively on CT examinations of the abdomen and pelvis of a histologically diverse group of benign and malignant solid in girls and women presenting with pelvic pain, where CT (per- ovarian masses with special emphasis on MRI . formed either with or without IV contrast) is the initial modality utilized because a gynecologic condition is not specifically sus- Educational Goals/Teaching Points: The goals are to list the pected . We have seen multiple patients where this scenario various solid benign and malignant masses encountered in the occurred, in patients ranging from the preteen years to postmen- ovaries; identify their distinctive imaging features on pelvic MRI opausal women, and have either established or suggested the and to define a diagnostic approach; and discuss the imaging diagnosis prospectively . The purpose of this exhibit is to demon- features of various complications associated with them . strate our experience with CT in this situation, to correlate with subsequent sonographic examinations if performed, and to Key Anatomic/Physiologic Issues and Imaging Findings/ review the relevant radiology literature on ovarian torsion . Techniques: In this exhibit we present imaging (with emphasis on MR imaging) of solid ovarian masses including the sex cord- Educational Goals/Teaching Points: Radiologists may not nec- stromal neoplasms (fibroma, thecoma and fibrothecoma), germ essarily suspect ovarian torsion when an abnormal ovary is iden- cell tumors (teratoma, dysgerminoma, and endodermal sinus tified on CT . The spectrum of appearances includes a simple cyst tumors), mesenchymal tumors (leiomyoma), solid epithelial-stro-

268 El e c t r o n i c Ex h i b i t s : GU/OB/GYN mal neoplasms (Brenner tumor) and metastases . Uncommon OM, but some cases remain undetermined because of atypical or manifestations and complications are also highlighted and a a specific appearance . MRI is the best imaging modality for diag- diagnostic approach is defined . nosis and characterization of OM . The purpose of this exhibit is to describe a systematic imaging approach to correct diagnosis Conclusion: A knowledge of the varied appearances of the wide through depicting discriminant MRI features of OM and their spectrum of solid ovarian masses helps in timely diagnosis and pathologic counterpart management of these relatively uncommon and usually benign lesions . One needs to be well versed with characteristic imaging Educational Goals/Teaching Points: The goals are to review features of various complications associated with them to initiate the classification of OM; describe the epidemiology, pathophysi- an immediate management . ology, and clinical features of OM; demonstrate the utility of MRI in the diagnosis and characterization of OM; describe MR exami- nation technique for a comprehensive evaluation of OM, depict E276. MR Imaging Features of Ovarian Stromal Tumors and suggest a systematic MRI approach to correct diagnosis Bharwani, N.; Dilks, P.; Sahdev, A.; Reznek, R.; Rockall, A. Barts through depicting discriminant MRI features of OM and their and The London NHS Trust, London, United Kingdom pathologic counterpart . Address correspondence to N. Bharwani (nishatbharwani@gmail. com) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: MRI for evaluation of OM is better performed with a Background Information: Ovarian stromal tumors arise from high field magnet (1 .5T) using a phased-array surface coil . A primitive sex cord and stromal components of the ovary and myorelaxant agent is intramuscularly injected before starting the account for most hormonally active tumors . They comprise procedure in order to reduce artifacts caused by intestinal peri- approximately 8% of all ovarian tumors and can be further sub- stalsis . The imaging protocol includes two 8 mm-thick/1 mm classified according to their histological components . The most spaced, T1-and T2-weighted fast spin echo (FSE) sequences with common types are granulosa cell tumors (GCTs), fibrothecomas/ elevated matrix and large field of view, followed by three high- thecomas, and Sertoli-Leydig cell tumors . resolution FSE T2-weighted sequences in three orthogonal spatial orientations and by an axial T1-weighted sequence with fat sup- Educational Goals/Teaching Points: The goals are to review pression . After IV contrast agent administration, a 3D T1-weighted the pathophysiology of ovarian stromal tumors, and discuss and fast spoiled gradient echo dynamic acquisition is achieved in illustrate the characteristic MRI features and secondary signs order to better evaluate lesion vascularity and peritoneal carcino- associated with the various tumor subtypes . matosis . Mature cystic teratomas, cysts, endometriomas, leiomyo- mas, fibromas, tecomas, germinomas and other OM can be accu- Key Anatomic/Physiologic Issues and Imaging Findings/ rately diagnosed and characterized on the basis of T1-weighted, Techniques: This pictorial review will demonstrate characteristic T2-weighted, and fat-saturated T1-weighted MRI findings and MR features of ovarian stromal tumors and associated secondary through evaluation of their enhancement after IV contrast agent signs of excess hormone production, e .g . endometrial hyperpla- administration . sia . Each subtype of stromal tumor has characteristic imaging fea- tures . GCTs are multiloculated cystic masses with variable solid Conclusion: MRI is the best imaging modality for diagnosis and portions which can be associated with endometrial abnormali- characterization of ovarian masses . Once the clinical and patho- ties . Fibromas and thecomas are usually solid masses with low logic features of ovarian masses are known, MRI allows a system- signal intensity on T1- and T2-weighted MRI and a variable atic approach to correct diagnosis by analyzing their discriminant degree of calcification or degeneration . Sertoli-Leydig cell tumors imaging features: morphology, signal intensity and enhancement are generally well-defined, enhancing solid masses with intratu- patterns . moral cysts of varying sizes .

Conclusion: Knowledge of the clinical signs and characteristic E278. An Illustrative Review of Cross-Sectional Imaging MR features of ovarian stromal tumors can be used by the inter- Appearances After Uterine Fibroid Embolization (CME Credit preting radiologist to differentiate these tumors from the more Available) common ovarian epithelial tumors . This information can help cli- Verma, S.1; Bergin, D.1; Baltarowich, O.1; Gonsalves, C.1; nicians to guide further investigation, plan the extent of surgery Lev-Toaff, A.2; Mitchell, D.1; Nazarian, L. 1. Thomas Jefferson and assess prognosis . University Hospital, Philadelphia, PA; 2. Hospital of the University of Pennsylvania, Philadelphia, PA Address correspondence to S. Verma ([email protected]) E277. Characterization of Undetermined Ovarian Masses with MRI: Discriminant Imaging Features and Pathologic Background Information: Uterine fibroid embolization (UFE) is Correlation an effective treatment for symptomatic uterine fibroids, and a Missere, M.; Restaino, G.; Occhionero, M.; Cucci, E.; Ciuffreda, M.; good alternative to surgical management . Major complications Sallustio, G. Catholic University of Sacred Heart, Campobasso, following UFE are rare . There is about an 8 .5% short term and Italy 1 .25% serious complication rate . Postprocedural imaging is rou- Address correspondence to G. Restaino ([email protected]) tinely performed to evaluate effectiveness of treatment and to identify potential post UFE complications . Background Information: Preoperative characterization and determination of a degree of suspicion for malignancy of ovarian Educational Goals/Teaching Points: The goals are to identify masses (OM) is critical and depends largely on imaging appear- the spectrum of findings on MRI and CT performed after UFE; to ance . Ultrasound can usually diagnose and characterize most of illustrate common and uncommon MRI and CT features after 269 El e c t r o n i c Ex h i b i t s : GU/OB/GYN successful, unsuccessful and complicated UFE, and to discuss terectomy are ureteral fistula, lymphocele, pelvic infection, and post UFE complications that requires urgent medical or surgi- hemorrhage . Late complications of radiation therapy include rec- cal intervention . tovesical fistula, sigmoiditis, rectal stricture, ureteral stricture, and sacral insufficiency fracture . Sites of recurrence are the pelvis, Key Anatomic/Physiologic Issues and Imaging Findings/ lymph nodes, and distant sites . Techniques: Imaging findings include typical post UFE appear- ances, fibroid location changes, fibroid vascularity, patterns of cal- Conclusion: Knowledge of the normal therapeutic changes and cification, fibroid recurrence and regrowth, gas after UFE: ster- the spectrum of recurrent tumor in patients with cervical carcino- ile and infectious, adenomyosis following UFE, intermittent uri- ma is important for accurate interpretation of follow-up MR nary retention, uterine necrosis, and pulmonary embolism . images .

Conclusion: The MRI and CT appearances vary depending upon E280. Utilization of Novel Extended Echo Train Acquisition the time interval after UFE and success of the procedure . CT fol- 3D MRI Sequence for Investigation of Uterine Anomalies lowing UFE may be requested because of acute pelvic pain or Agrawal, G.; Riherd, J.; Hinshaw, J.; Sadowski, E. University of chest discomfort or pyrexia or for an unrelated indication . Wisconsin, Madison, Madison, WI Awareness of expected and abnormal imaging findings is essen- Address correspondence to G. Agrawal ([email protected]) tial for correct diagnosis and treatment . Radiologists should be familiar with the range of post UFE appearances on MRI and CT Objective: The objective is to compare 3D fast spin echo (FSE) to better aid clinicians in correct diagnosis and treatment . eXtended Echo Train Acquisition (XETA) and 2D fast-recovery fast spin echo (FRFSE) MR imaging sequences and their respective 3D reconstructions in the evaluation of congenital uterine anomalies . E279. Uterine Cervical Carcinoma after Therapy: MR Imaging Findings Materials and Methods: This retrospective study received insti- Restaino, G.; Missere, M.; Ciuffreda, M.; Cucci, E.; Occhionero, M.; tutional review board exemption, and informed consent was not Sallustio, G. Catholic University of Sacred Heart, Campobasso, required . The study was compliant with the HIPAA . Between Italy June, 2006 and May, 2008, both 2D FRFSE and 3D-FSE-XETA Address correspondence to G. Restaino ([email protected]) imaging was performed on all female patients referred to our department for a noncontrast MRI of the pelvis to assess for uter- Background Information: Cervical carcinoma (CC) is the third ine anomalies . T2-weighted 2D FSE acquisitions were performed most common gynecologic malignancy . Although patients now in axial, sagittal and oblique (coronal to uterus) planes . (Time to survive longer due to radiation therapy and more effective chem- repeat [TR]=2,500 milliseconds, time to echo [TE]=85 millisec- otherapy, CC is also one of the most frequent causes of death in onds, FOV=24-36 cm, matrix=320 x 256, 12-24 slices 5 mm thick women . The choice of primary treatment demands clinical judg- with 1 .5 mm skips, scan time 4 5. minutes per plane ~13 min- ment and depends on patient’s age and FIGO stage at diagnosis, utes for three planes .) 3D-FSE-XETA sequence was performed for ranging from conization in stage IA, to surgery or radiation thera- a volumetric T2-weighted acquisition (TR=2,500 milliseconds, py in stages IB to IIA and to radiation therapy combined with TE=105 milliseconds, FOV=24 cm, matrix=256 x 224 x 128, slab chemotherapy in stages from IIB to IVA . After primary treatment, coverage=18 cm, slice thickness=1 .6 mm, scan time five min- patients are usually followed up with MR . Deep knowledge of utes) . Zero filling (since interpolation) in three dimensions was imaging findings after therapy is crucial in order to accurately used to reconstruct 0 5. x 0 .6 x 0 .7 mm voxels, allowing recon- evaluate the patient’s response and the potential complications structions of the 3D data in multiple planes . A retrospective of treatments, and in order to correctly differentiate normal post- review of all pelvic MRI’s yielded 16 patients with uterine anoma- treatment findings from recurrence of disease . lies . Curvilinear 3D reconstructions were performed on these 16 studies utilizing both the 2D FRFSE and 3D-XETA images . Educational Goals/Teaching Points: The goals are to describe Evaluation for image quality based on tissue contrast, edge the MR imaging appearances of post-therapy changes in patients sharpness, image blurring and motion artifact was performed by with CC, that is, anatomic changes resulting from surgery and a radiologist, who was blinded to the type of sequence used for those changes induced by radiation therapy; illustrate the compli- reconstructions . Each assessment was given a score using a scale cations of hysterectomy or pelvic irradiation performed for treat- of 1-5 (1=poor; 5=excellent) . Overall image quality and diagnos- ment of CC, and review the imaging features of recurrent CC in tic confidence was determined by the mean of all scores and sin- the pelvis and lymph nodes and of distant metastases . gle tailed paired student’s t test was performed .

Key Anatomic/Physiologic Issues and Imaging Findings/ Results: Mean overall image quality of the 3D reconstructions Techniques: A normal vaginal cuff after hysterectomy appears as was significantly better (p<0 .000002) for FSE XETA (4 .03) com- a smooth, low-signal-intensity muscular wall on T2-weighted MR pared to FRFSE (2 55). . The level of diagnostic confidence though images . In some cases, however, fibrotic scar tissue is present at statistically insignificant (p=0 21),. was better for FSE XETA (4 31). the vaginal vault . Metallic clips along the pelvic side wall can be compared to FRFSE (4 18). . Additionally, the XETA volume data for detected at the site of lymph node dissection as low-signal-inten- reformat could be acquired in approximately five minutes as sity foci . Early and significant decreases in the signal intensity and opposed to more than 13 minutes required to obtain the 2D volume of the tumor at MR imaging indicate a good response to FRFSE data in necessary three plane acquisition . radiation therapy . Reconstitution of the normal zonal anatomy of the cervix and the presence of homogeneous low signal intensity Conclusion: 3D FSE XETA provides superior image quality and cervical stroma at MR imaging are reliable indicators of a tumor- improved 3D reconstruction in less acquisition time compared to free postirradiation cervix . The major complications of radical hys- 2D FRSFE in the evaluation of uterine anomalies .

270 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

E281. MR Imaging Features of Uterine Sarcomas between emergent and nonemergent entities based on sono- Bharwani, N.1; Jelbert, A.1; Tunariu, N.2; Babar, S.2; Sahdev, A.1; graphic findings is essential for patient management in clinical Rockall, A.1; Reznek, R.1 1. Barts and The London NHS Trust, practice . London, United Kingdom; 2. Imperial College HealthCare NHS Trust, London, United Kingdom Educational Goals/Teaching Points: The goals are to review Address correspondence to N. Bharwani (nishatbharwani@gmail. and understand normal physiologic changes in the ovaries and to com) differentiate sonographic presentations of normal physiology from underlying pathologic entities; demonstrate typical physio- Background Information: Uterine sarcomas are uncommon, logic sonographic imaging patterns in the adnexa, and to distin- aggressive tumors of mesenchymal origin accounting for 5-8% of guish abnormal sonographic imaging patterns in different patho- all uterine malignancies . Although uterine sarcomas can be indis- logic states . tinguishable from endometrial carcinoma or atypical fibroids on MRI, there are certain features that can suggest these rare tumors Key Anatomic/Physiologic Issues and Imaging Findings/ preoperatively . The distinction between atypical fibroids and sar- Techniques: Classic sonographic imaging findings in the pelvis comas significantly alters the patient’s treatment strategy . form the cornerstone of diagnosis in female patients with pelvic Although distinction between endometrial cancer and endometri- pain . Pattern recognition based on the sonographic spectrum of al sarcomas can be made on endometrial biopsy, MR features different pathological entities vs . normal physiologic changes pro- may also be helpful where the biopsy is inconclusive . vides the roadmap for diagnosis, treatment and follow up in Preoperative diagnosis of a sarcoma, may avoid inappropriate the clinical setting . A pelvic ultrasound is the basic and ideal surgery and potentially affect patient outcome . method of investigation in the reproductive or postmenopausal age groups . Besides providing the foundation for diagnosis, easy Educational Goals/Teaching Points: The goals are to discuss follow up can also be obtained . This educational exhibit will elu- the pathology of uterine sarcomas, and illustrate typical MRI cidate the sonographic patterns that provide the basis of recogni- appearances of common histological variants . tion of various physiologic and abnormal patterns in common and uncommon pathological conditions . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The most common histological variants are: leiomy- Conclusion: Ultrasound has remained the gold standard in osarcoma (LMS), carcinosarcoma/malignant mixed müllerian female pelvic imaging both on an emergent and nonemergent tumor (MMMT) and endometrial stromal sarcoma (ESS) . Other basis while providing a safe modality for follow up of pelvic rarer sarcomas containing tissues foreign to normal uterine tissue pathology or to confirm normal physiologic findings . Patient include rhabdomyosarcoma . LMS are characteristically large inter- management and triage is dependent on the sonographic find- mediate T2-weighted signal intensity masses replacing normal ings based on pattern recognition and their clinical implication . uterine architecture with pockets of high T2-weighted signal rep- resenting areas of hemorrhage or cystic degeneration . MMMT are endometrial-based tumors, heterogeneously hyperintense on T2, E283. Female Pelvic Pain...Beyond the Adnexal Mass homogenously hypointense on T1 and enhance with gadolinium . Shively, A.; Kasales, C.; Collins, B.; Neutze, J. Penn State Hershey Appearances of ESS vary with grade of tumor ranging from a sim- Medical Center, Lewisburg, PA ple endometrial mass to large, irregular infiltrative, aggressive Address correspondence to C. Kasales ([email protected]) tumors . Background Information: Women and adolescent girls with Conclusion: Knowledge of typical MR features associated with acute pelvic pain make up a large percentage of patients seen in uterine sarcomas enables the reporting radiologist to suggest this the diagnostic ultrasound practice . Although making the appro- rare diagnosis preoperatively . This is advantageous to gynecologi- priate diagnosis of adnexal processes such as ectopic pregnancy cal oncology surgeons allowing more radical surgical planning and ovarian masses/ovarian torsion is important in these and influences patient’s subsequent management . patients, there is a far wider variety of pathology that may present with acute pelvic discomfort . Our goal is to educate the viewer as to the broad spectrum of common and not-so-com- E282. Images from the Under Belly: Pattern Recognition in mon causes of pain that are encountered when evaluating young the Adnexa girls and women with acute pelvic discomfort . Cornejo, S.; Chandrasekhar, C. University of Texas Health Science Center Houston, Houston, TX Educational Goals/Teaching Points: Our cases stress the Address correspondence to A. Chandrasekhar (chitra.chan- importance of combining a firm knowledge of pelvic anatomy as [email protected]) well as the various pathophysiologic processes that may be present . A systematic imaging approach to the ultrasound evalua- Background Information: Acute pelvic pain is a common pres- tion of females with pelvic pain is key to accurate diagnosis . entation in the female patient on an emergent and nonemergent Close correlation of imaging findings with age, reproductive/sur- basis . Ultrasound remains in the forefront of female pelvic imag- gical history, available clinical and laboratory data, and a firm ing and is easily available on an emergent basis . Pattern recogni- knowledge of the types of pathology commonly affecting the tion of adnexal sonographic findings is crucial to recognize and uterus and adnexa is also important . In many patients, the source understand normal physiologic changes vs . adnexal pathology as for pain may be from the ovary . However the fallopian tube, uter- the cause for pelvic pain . A subjective pattern recognition us or even unexpected organs such as a transplanted kidney can approach has been shown to have high sensitivity and specificity also be the source of symptoms . for differentiation of benign vs . malignant disease . Differentiation

271 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

Key Anatomic/Physiologic Issues and Imaging Findings/ which will be demonstrated through the use of cases include: Techniques: The uterus is a frequently forgotten source of pelvic C-section scar, cornual, cervical, abdominal, intrasplenic, and het- pain . Knowledge of the various pathologic processes affecting the erotopic pregnancy . Differentiation from mimics, such as preg- uterus in different age ranges (such as cervical stenosis, malig- nancy in the anomalous uterus and other adnexal masses, as nancy, and scar ectopic) is the key to differentiating the imaging well as other pitfalls in diagnosis will be discussed . The role of findings, which may otherwise not be very specific . Familiarity 3D ultrasound, MRI and CT as an adjunct to 2D ultrasound for with less common surgical procedures, such as supracervical hys- problematic cases will be discussed . The role of imaging in guid- terectomy, is also prudent, and may allow the sonographer or ing treatment and management of the pregnancy of unknown sonologist to more readily recognize postoperative processes location will also be presented . such as stump abscess . Women who have undergone assisted reproduction are at risk for less frequently seen complications Conclusion: Familiarity with the imaging appearance of unusual such as interstitial and heterotopic ectopic . Finally, types of ectopic pregnancy will allow for accurate and prompt as clinicians we need to remember that pathology from other diagnosis . Multimodality imaging may play an important role in pelvic organs, such as transplanted kidneys, may be a source for differentiation of ectopic pregnancy from other acute disorders . pelvic pain . E287. Cesarean Section: Not Only a Convenience. Conclusion: By thinking “beyond the ovary” and correlating the Multimodality Imaging Review of Complications imaging findings with available clinical and laboratory data, each McLean, L.; Kennedy, A.; Shaaban, A.; Woodward, P. University of clinician can be better prepared to evaluate common and less Utah, Salt Lake City, UT common causes of pelvic pain . Address correspondence to L. McLean ([email protected]. edu)

E286. Challenges and Pitfalls in the Diagnosis of Ectopic Background Information: The purpose of this exhibit is to Pregnancy: Multimodality Imaging Evaluation (CME Credit review the multimodality imaging appearance of cesarean sec- Available) tion complications; illustrate diagnostic criteria for both common Chaudhri, Y.1; Mauch, E.2; Oto, A.2; Slywotzky, C.1; Timor-Tritsch, and rare complications seen in the pregnant and postpartum I.1; Bennett, G.1 1. New York University Medical Center, New York, patient, and discuss appropriate indications for supplemental NY; 2. University of Chicago, Chicago, IL imaging in these patients . Address correspondence to G. Bennett (genevieve.bennett@med. nyu.edu) Educational Goals/Teaching Points: The major educational goals of this exhibit include multimodality imaging review of the Background Information: Ectopic pregnancy is one of the lead- key diagnostic findings in pregnancy complications—placenta ing causes of maternal morbidity and mortality . There may be accreta, increta, percreta, uterine rupture, and operative bladder, unusual sites of pregnancy implantation which present a diag- bowel and vascular injury; postpartum complications—infection nostic challenge, both clinically and at imaging . Intra- and extrau- (endometritis, pyelonephritis), bowel (ileus, perforation), pelvic terine pregnancy may coexist, and this may also present a diag- vein thrombosis, uterine scar dehiscence, uterine scar ectopic nostic challenge . The location of the pregnancy may not be iden- pregnancy, and IUD malposition . tified (pregnancy of unknown location [PUL]), and the patient may be treated on the basis of clinical and laboratory findings . Key Anatomic/Physiologic Issues and Imaging Findings/ Conventional gray scale and color Doppler ultrasound serve as Techniques: The exhibit will include uterine anatomy—en- the cornerstone of imaging of the ectopic pregnancy; however, dometritis, placenta accreta, increta and percreta and uterine 3D ultrasound and MRI may serve as problem-solving tools . scars status postcesarean section, and adjacent pelvic anatomy— Occasionally CT may be performed in the setting of an unsus- bladder and vascular structures . pected ectopic or unusual intra-abdominal location . The purpose of this exhibit is to review the imaging findings in ectopic preg- Conclusion: Both common postpartum complications and unu- nancy with an emphasis on unusual sites of pregnancy implanta- sual cesarean section scar-related complications are more fre- tion . The role of 3D ultrasound, MRI and CT in the diagnosis of quently imaged due to the increased incidence of operative unusual or complicated cases will be discussed . deliveries . MRI and CT may be supplemental for further charac- terization . Accurate and timely diagnosis of the accreta spectrum Educational Goals/Teaching Points: The diagnosis of ectopic is imperative due to the potential for life-threatening maternal pregnancy, especially when the site of implantation is unusual, hemorrhage and fetal demise . may be challenging . Familiarity with the imaging appearance of unusual types of ectopic pregnancy is essential for appropriate diagnosis . Although 2D ultrasound remains the initial imaging E288. Cesarean Section: Imaging of Acute and Chronic study of choice, 3D ultrasound, MRI and CT may serve as impor- Complications tant problem solving tools in unusual or complicated cases . Horrow, M.; Rodgers, S.; Lee, J.; Larrauri, D. Albert Einstein Medical Center, Philadelphia, PA Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to M. Horrow ([email protected]) Techniques: In this exhibit, the epidemiology, pathophysiology and clinical features of ectopic pregnancy will be discussed . This Background Information: In 2005 Cesarean delivery accounted will be followed by examples of ultrasound findings of ectopic for approximately 1/3 of all births in the USA . Despite its safety, a pregnancy with an emphasis on less common sites of pregnancy variety of acute complications, often more frequent with obesity implantation . Examples of unusual types of ectopic pregnancy and repeat C-section can ensue . In addition there is a growing

272 El e c t r o n i c Ex h i b i t s : GU/OB/GYN population of women with a prior history of C-sections, who 19% were avascular (type 0), 19% had minimal vascularity (type require pelvic imaging . Uterine adhesions may cause difficulty I), 37% had moderate vascularity (type II), 7% had marked vascu- with sonographic imaging . The C-section scar also leaves the larity (type III), and 19% had a single feeding vessel or focus of patient vulnerable to several rare, but unique diagnoses that are vascularity (type IV) . Peak velocities ranged from 10 to 108 cm/ now made with increasing frequency . Review of post C-section second (average 35 7. cm/second) . Resistive indices in arterial imaging over the past 3 .5 years yielded examples of normal and waveforms ranged from 0 .33 to 0 7. (average 0 .5) . Of those type 0 abnormal acute appearances and a variety of chronic complica- vascularity, 45% had RPOC . 83% of Type I had RPOC and 100% tions . Familiarity with the “normal” appearance of the immediate of types II-IV had RPOC . An echogenic mass had moderate specif- and chronic post C-section pelvis is necessary to appreciate true icity (78%) but low sensitivity (26%) for RPOC . pathologic findings and to understand complications related to the C-section scar . Conclusion: We identified five types of color Doppler appear- ance of RPOC that provide additional information of the likeli- Educational Goals/Teaching Points: Unique acute bleeding hood of the presence of RPOC . The presence of any vascularity complications after C-section can include bladder flap and sub- is highly correlated with retained products of conception while fascial hematomas . Wound complications after C-section may the lack of vascularity can be seen in both intrauterine clot as include uterine dehiscence . Scarring from C-sections may cause well as avascular RPOC . adhesions that tether the uterus to the anterior abdominal wall making sonographic imaging extremely difficult . Complications of the uterine scar include: ectopic pregnancy, IUD malposition, E290. Diagnosis of Postpartum Complications repository for menstrual blood and endometrial implants . Ro, K.; Kamaya, A.; Desser, T.; Chang, P.; Benedetti, N. Stanford University, Stanford,CA Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to K. Ro ([email protected]) Techniques: This didactic exhibit uses CT and ultrasound to demonstrate normal acute C-section appearance; examples of Background Information: Postpartum complications are report- acute complications: superficial collections and hematomas, cel- ed to occur in up to 10% of all deliveries and include post-par- lulitis, subfascial hematomas, wound dehiscence, bladder flap tum hemorrhage, obstetrical trauma, thromboembolic complica- hematomas, uterine rupture, endometritis, pelvic vein thrombosis tions and puerperal infections . This exhibit will review the diag- and abscess; normal chronic C-section appearance: adhesions nostic considerations in the evaluation of postpartum complica- resulting in abnormal uterine position and the uterine scar, and tions, and the correlative radiological imaging findings and treat- examples of chronic C-section scar complications: repository for ment options . menstrual blood, ectopic pregnancy, IUD malposition and endometrial implants . Educational Goals/Teaching Points: The educational goals include demonstrating the range of normal findings in the post- Conclusion: This exhibit will demonstrate acute and chronic com- partum uterus by ultrasound, CT and MRI; illustrating the spec- plications of C-section using CT and ultrasound . Discussion of the trum of postpartum complications, their clinical presentation and procedure and display of normal immediate findings will allow the correlative imaging findings relevant to the diagnosis; high- appreciation of the unique types of hematomas and abscesses, lighting the preferred imaging modality that best illustrates a spe- and wound complications in the acute situation . In the chronic cific diagnosis, and describing specific radiologic pearls that can phase imaging will demonstrate the appearance of the normal aid in making an accurate diagnosis as well as the potential pit- C-section scar, difficulties with ultrasound imaging related to falls to avoid . adhesions, and complications related to the C-section scar . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The imaging techniques and findings relevant to the E289. Color Doppler Evaluation of Retained Products of following postpartum complications will be described and Conception: Potential Guide to Clinical Management (CME include postpartum hemorrhage—uterine atony, retained prod- Credit Available) ucts of conception; obstetrical trauma—uterine dehiscence/rup- Kamaya, A.; Petrovitch, I.; Chen, B.; Jeffrey, R. Stanford University, ture, postsurgical trauma including small bowel obstruction and Stanford, CA uterovesicular fistula, delayed postpartum complication including Address correspondence to A. Kamaya ([email protected]) cesarean section scar, ectopic and endometriosis in a cesarean section scar; thromboembolic complications—ovarian vein throm- Objective: The objective was to characterize color Doppler bosis, amniotic fluid embolism; puerperal infection—endometri- imaging features of retained products of conception (RPOC) tis, abscess formation, postpartum appendicitis, pyelonephritis, with grayscale correlation . and other postpartum complications—posterior reversible encephalopathy syndrome, HELLP syndrome . Materials and Methods: Clinically suspected cases of RPOC between January, 2005 and February, 2008 were reviewed . Conclusion: The accurate diagnosis of various postpartum com- Patient data and relevant color Doppler and grayscale features plications requires both an understanding of the normal postpar- were recorded . tum appearance of the uterus and the range of potential compli- cations in order to choose the most accurate diagnostic modality Results: A total of 269 patients referred for sonographic evalua- to confirm a suspected diagnosis . tion for RPOC were identified . Thirty-four patients had confirmed pathologic diagnosis, 27 of whom had RPOC . In those with RPOC,

273 El e c t r o n i c Ex h i b i t s : GU/OB/GYN

E291. Doppler Evaluation of the Fetal Middle Cerebral sound and MRI within one week of each other . Images from Artery (CME Credit Available) both examinations were reviewed and correlated with prenatal Hogan, L.; Gaudier, F. Mayo Clinic, Jacksonville, FL diagnosis and postnatal outcome . A comparison was made to Address correspondence to L. Hogan ([email protected]) determine in which cases MRI provided complementary vs . redundant information . Background Information: Fetal Doppler applications are expand- ing at a rapid rate . Of particular interest is Doppler interrogation of Results: In 31 patients (58%), MRI findings did not provide addi- the fetal middle cerebral artery . The right and left middle cerebral tional information to ultrasound findings . In 15 patients (28%), arteries are relatively straight branches of the circle of Willis that MRI findings were complementary to the ultrasound examination carry more than 80% of the cerebral blood flow . Careful measure- but did not significantly change the clinical management . In ment of the velocity, resistive indices and evaluation of the wave- seven patients (13%), the clinical management was changed due form can provide useful information to the obstetrician regarding to MRI findings . Our experience suggests that the majority of fetal fetal anemia, intrauterine growth restriction and fetal hypoxemia MRI studies yield redundant information . In most of the clinical which can in turn guide management of the pregnancy . situations we analyzed, prenatal ultrasound provided adequate information to diagnose fetal abnormalities in high risk pregnan- Educational Goals/Teaching Points: The purpose of this exhibit cies and guide subsequent management decisions . In a minority is to discuss the utility of Doppler evaluation of the middle cere- of cases MRI did yield additional information but did not change bral artery including applications in fetal anemia, intrauterine clinical management . In the few cases where management was growth restriction and hypoxemia/placental insufficiency and changed, the complications were more related to maternal fac- how this affects the obstetricians management of the patient; tors than fetal concerns . There is a fine line of distinction discuss the appropriate technique for measurement of velocity, between scenarios in which MRI may make a difference in man- resistive indices and waveform capture with special attention to agement and when it does not add to what is already known potential pitfalls and expected changes to the above parameters from prior fetal ultrasound . The benefits of doing fetal MRI as the gestation progresses, and review real life normal and should therefore be carefully weighed before performing an abnormal cases as seen in the maternal fetal medicine clinic . expensive and frequently redundant exam .

Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: As the utilization of fetal MRI increases, an objective Techniques: The cerebral circulation is normally a high resistance evaluation of its perceived and actual benefits vs . traditional circulatory system with continuous forward flow throughout the ultrasound evaluation is necessary in each clinical scenario . cardiac cycle . When fetal hypoxemia is present, the fetus com- pensates by redistributing blood flow to the brain, heart and adrenals while reducing flow to the remainder of the body, a E293. Fetal MRI: Basic Technique, Fetal Anomalies and phenomenon known as “brain sparing” . The middle cerebral Maternal Abdomen (CME Credit Available) artery is easily insonated in both the near and far field in the Lee, H.1; Prince, M.1,2; Prowda, J.1; Laifer-Narin, S.1 1. Columbia fetus making this vessel an ideal choice for evaluation . In the University College of Physicians and Surgeons, New York, NY; 2. transverse plane of the fetal head near the base of the skull, the Weill Cornell Medical College, New York, NY proximal and distal middle cerebral arteries course almost paral- Address correspondence to H. Lee ([email protected]) lel to the ultrasound beam . Measurements and waveforms obtained near the origin of the vessel from the internal carotid Background Information: Fetal MR imaging is continuing to artery have been shown to be the most reproducible between gain popularity as it offers operator-independent imaging in any operators . Careful attention to technique, specifically the angle of image plane with excellent soft tissue contrast and fine detail, as insonation, is paramount to ensure accurate evaluation . well as a large field of view . MR imaging also avoids exposure of the mother and fetus to ionizing radiation and does not require Conclusion: The Doppler evaluation of the middle cerebral artery intravenous contrast material . With the development of faster MR in the fetus is a powerful tool for the obstetrician and when seri- imaging sequences, greater anatomic detail of the fetus can be ally measured may obviate the need for more invasive tests/ visualized without the need for sedation to reduce fetal motion monitoring, such as amniocentesis . artifact . Thus, it is necessary to understand the MR imaging tech- niques and to recognize fetal anomalies for optimal examina- tion and image interpretation . E292. Fetal Ultrasound and MRI: Practical Roles in Clinical Management of the Neonate (CME Credit Available) Educational Goals/Teaching Points: This educational exhibit Bennett, B.; Johnson, K.; Angtuaco, T. University of Arkansas for aims to familiarize radiologists with basic technique of fetal MR Medical Sciences, Little Rock, AR imaging, a variety of fetal anomalies and complications involving Address correspondence to B. Bennett (bennettbrittonm@uams. the maternal abdomen . edu) Key Anatomic/Physiologic Issues and Imaging Findings/ Objective: The goal was to explore clinical situations in which Techniques: A variety of anomalies involving the fetus will be MRI played a complementary role to ultrasound and instances in discussed: bronchopulmonary sequestration, conjoined twins, which MRI did not add any additional information to sonographic sacrococcygeal teratoma, gastroschisis, omphalocele, congenital diagnosis and was therefore redundant . diaphragmatic hernia, limb body wall complex, central nervous system teratoma, vein of Galen aneurysm, myelomeningocele, Materials and Methods: A review of medical records over the tuberous sclerosis, etc . Complications involving the maternal past five years identified 53 patients who had both fetal ultra- abdomen, such as a pregnancy in the rudimentary horn of a uni-

274 El e c t r o n i c Ex h i b i t s : Musculoskeletal cornuate uterus, ectopic pregnancy, acute appendicitis during E295. Off on the Right Foot: A Pictorial Exhibit on pregnancy and placental abnormalities will be discussed . Conventional Radiography and MDCT of Talar Injuries Wibskov, J.; Rahal, A.; Loredo, R.; Garcia, G. University of Texas Conclusion: While still evolving, fetal MR imaging contributes to Health Science Center at San Antonio, San Antonio, TX the decision-making processes regarding pregnancy, patient Address correspondence to J. Wibskov ([email protected]) counseling, delivery management, and planning for prenatal or postnatal care . Background Information: Reportedly, 3-5% of foot fractures involve the talus . As the bone responsible for both supporting the tibia and communicating directly with the calcaneus and navicular, fractures here are likely under-reported . Indeed, while both radi- Mu s c u l o s k e l e t a l ography and MDCT are consistently sensitive to ankle and calca- neal fractures, talar fractures tend to be radiographically occult . E294. Tarsal Coalitions Variability amongst detection of talar fractures depends greatly on Brown, K.; Walker, E. Penn State Hershey Medical Center, fracture location . The purpose of this exhibit is to first review the Hershey, PA anatomy of the talus and illustrate the classification of talar frac- Address correspondence to K. Brown ([email protected]) tures . Secondly, a description of the mechanisms of injury and patterns of talar trauma will demonstrate these classifications . Background Information: Tarsal coalition is an entity that can Finally, a comparison of plain film and MDCT presentations of talar be overlooked in patients with foot and ankle pain . Awareness of injuries will highlight cases of radiographically occult fractures . the common types of tarsal coalitions and their radiographic appearance is important for diagnosis and treatment planning . Educational Goals/Teaching Points: The goals are to provide a pictorial illustration and review the anatomy and classification of Educational Goals/Teaching Points: The purpose of this exhibit common talar fractures and provide an understanding of mecha- is to demonstrate multimodal findings in the diagnosis of tarsal nisms of injury to the foot and ankle helps direct attention to the coalition and to delineate the secondary findings important for probable sites of injury . MDCT is a useful adjunct to radiography guiding management . At the conclusion of this exhibit, the radiol- for the evaluation of complex or occult talar injuries . ogist should be able to 1) understand key findings and anatomic structures involved in tarsal coalition, 2) document joint involve- Key Anatomic/Physiologic Issues and Imaging Findings/ ment and type of coalition, and 3) document secondary findings Techniques: Talar fractures are divided into types based on the and degenerative changes pertinent to clinical management . three main anatomical regions of the talus: the body, head and neck . Injuries to the body can be further categorized as belong- Key Anatomic/Physiologic Issues and Imaging Findings/ ing to the dome, to the medial, lateral and posterior processes, Techniques: Tarsal coalitions may be fibrous, cartilaginous, or or the main body, extending from the upper articular surface osseous . Calcaneonavicular and talocalcaneal coalitions are most through the subtalar joint . Talar neck fractures are historically very common, and approximately 50% are bilateral . Calcaneonavicular clear on radiography . The three processes of the body, however, coalitions are often detectable on 45° internal oblique radio- are difficult to detect on plain film, and their fractures should be graphs as an irregular broad apposition of the calcaneus and suspected based on the mode of injury and clinical presentation . navicular and an elongated anterior calcaneal process on the lat- eral view (“anteater” sign) . Talocalcaneal coalitions frequently Conclusion: Anatomy of the talus, mechanisms of injury and involve the middle subtalar facet and often require CT or MRI for types of talar fractures are reviewed . Imaging findings of different conformation . Secondary signs of talocalcaneal coalition on plain talar injuries are depicted, comparing plain film radiography and film include absent middle facet sign, C sign, talar beak or curved MDCT findings . undersurface of the sustentaculum tali . Sequelae of tarsal coali- tion, including degenerative changes, are important to recognize and document for patient management and preoperative plan- E296. Ankle and Foot Fractures, MDCT Imaging vs. Plain ning . In general, resection is indicated for symptomatic talocalca- Film Evaluation neal coalitions involving <50% of the joint . For >50% involve- Wibskov, J.; Rahal, A.; Loredo, R.; Garcia, G. University of Texas ment, subtalar arthrodesis is preferred . Calcaneonavicular coali- Health Science Center at San Antonio, San Antonio, TX tions are generally resected . For patients with secondary degener- Address correspondence to J. Wibskov ([email protected]) ative changes, triple arthrodesis may be required . CT and MR imaging of the ankle and hindfoot should include imaging/recon- Objective: The purpose of our study was to assess the accuracy struction in the axial coronal and sagittal planes . T1 and proton of detection of foot and ankle fractures using radiographs as density-weighted images with T2-weighted images are generally compared to MDCT in patients with acute trauma . We further sufficient for MRI evaluation . Subarticular bone marrow edema at aimed to identify which types of injury specifically warrant evalu- the coalition can be seen on short-tau inversion recovery (STIR) ation with MDCT . or T2 fat saturation sequences . Materials and Methods: Radiographic records were retrospec- Conclusion: The diagnosis of tarsal coalition is often overlooked tively analyzed for this IRB-approved study . Between January 1, in the clinical differential diagnosis of foot and ankle pain . Thus, 2006 and July 7, 2007, a total of 559 patients received MDCT fol- it is important for the radiologist to recognize the key anatomic lowing radiographic examination of the ankle or foot . Inclusion abnormalities and pertinent secondary findings of tarsal coalition criteria were met by 303 patients (317 extremities; 214 male, to help guide management . 103 female) with acute ankle and/or foot trauma . We recorded the location of fractures diagnosed on plain films at the time of

275 El e c t r o n i c Ex h i b i t s : Musculoskeletal injury, and compared it with the MDCT results as the gold stand- Key Anatomic/Physiologic Issues and Imaging Findings/ ard . Agreement of the presence and the exact location of Techniques: Contrast-enhanced MR images help delineate a fracture(s) in each bone was calculated . The frequency of frac- variety of painful conditions in the foot and ankle: For infection, tures on plain films vs . MDCT images, the sensitivity for fracture noncontrast T1-weighted and short tau inversion recovery imag- detection, and the correlation between radiographic and CT ing can detect areas of abnormal edema, while contrast enhance- results were summarized using descriptive statistics . Detailed ment defines abscess and fistulous tracts as signal voids within agreement for findings in each bone was assessed using contin- areas of hyperemia, guiding surgical treatments . For subacute gency tables and Fisher’s exact tests . and chronic sprains, noncontrast MRI may show only heteroge- neous signal that could be either healing or scarring, while con- Results: Exams of 317 extremities showed a total of 783 frac- trast enhancement may show either intense enhancement indi- tures in 292 extremities (92%): ankle (137), calcaneus (123), cating chronic tears with hyperemia or old scar with absence of talus (69), midfoot (93) and forefoot (77) . The most common enhancement . Adjacent synovitis may also be detected . For teno- modes of injury were motor-vehicle-related trauma 39% synovitis, contrast enhancement distinguishes bland fluid from (118/303) and falls 38% (116/303) . The most common undetec- inflamed tendon sheaths . For plantar fibromas, focal enhance- ted fractures on initial radiographs were of the cuboid, intermedi- ment delineates multifocal lesions that may be undetected with- ate and lateral cuneiforms, and the lateral and medial processes out dye . For the forefoot, contrast detects tears of the metatar- of the talus . The sensitivity of plain film reports for talar and mid- sophalangeal joint capsule, areas of enhancement in adventitial foot fractures was 31% (21/68) and 29% (26/90), respectively . bursitis, and acute synovitis that can appear normal without dye . The calcaneus was the most commonly fractured bone; radio- For rounded tumors that appear homogeneous, contrast distin- graphs were sensitive to 77% (87/113) of these fractures . Five guishes cystic (i .e . ganglion) from solid (i e. . neuroma) . For foreign out of 14 (36%) Lisfranc injuries were radiographically occult . bodies, contrast may outline abscess or focal foreign body reac- The sensitivity of radiography for fractures of the tibia and fibula tions that help detect otherwise inconspicuous foreign bodies . was 85% (115/136) and, for metatarsal fractures, 73% (45/62) . Overall, positive plain film findings in the foot and ankle were Conclusion: Gadolinium-based contrast agents, when not con- moderately sensitive and highly specific for the different fractures traindicated, improve detection and characterization of a variety described in the ankle and calcaneus . of conditions of the foot and ankle .

Conclusion: In high-impact trauma patients with foot or ankle injuries suspicious for fractures or Lisfranc joint injuries, MDCT E298. Low T2 Signal in the Foot and Ankle: Classic Lesions can improve diagnostic accuracy . MDCT imaging is especially and Less Familiar Entities warranted in trauma patients with negative plain film exams . Wilde, G.1; Gakhal, M.1; Awan, O.2; 1. Christiana Care Health System, Newark, DE; 2. No Institutional Affiliation Address correspondence to G. Wilde ([email protected]) E297. The Utility of Contrast-Enhanced MRI for the Detection and Characterization of Foot and Ankle Pathology Background Information: The purpose of this exhibit is to illus- Abrahamian, H.1; Kier, R.1; Siroka, P.2; Feldman, A.1; Eterno, R.1; trate the spectrum and appearance of T2 hypointense disease Davis, D.1 1. Bridgeport Hospital, Bridgeport, CT; 2. Stamford entities that can be encountered on MRI of the foot and ankle in Hospital, Stamford, CT everyday clinical practice . We present several frequently encoun- Address correspondence to H. Abrahamian (harry.abrahamian@ tered lesions as well as a few less common entities . gmail.com) Educational Goals/Teaching Points: Illustrative cases have Background Information: Few articles have evaluated the ben- been selected from our institution and will be presented to the efit of adding contrast enhancement for MR images to diagnose viewer in a quiz format, followed by didactic material . Specific and characterize pathologies of the foot and ankle . Existing publi- distinguishing MRI features of entities that narrow the differential cations have differing opinions . One shows that there is no differ- diagnosis are highlighted . Pathologic features leading to MRI sig- ence in diagnosing bone marrow abnormalities when comparing nal characteristics are reviewed when this information is known . STIR images vs . T1-weighted contrast-enhanced fat-suppressed Correlation with plain radiographs is emphasized when these are MR images . Other articles report increased sensitivity and specifi- available . city in diagnosing osteomyelitis, syndesmotic injury, and bone healing by adding gadolinium-enhanced fat-suppressed MR Key Anatomic/Physiologic Issues and Imaging Findings/ images to nonenhanced MR images . Techniques: Entities covered include: systemic disorders, bone and soft tissue tumors, tumor-like conditions, foreign bodies, Educational Goals/Teaching Points: Diagnosis of synovitis and technical issues, coalition, and postsurgical findings . tenosynovitis utilizing MRI images without contrast relies on detection of either abnormal fluid or secondary soft tissue Conclusion: Although most pathologic entities present with edema . Intravenous gadolinium adds assessment of hyperemia hyperintense T2 signal in foot and ankle imaging, the differential and hypervascularity which are more consistent with synovitis . diagnosis for lesions with hypointense T2 signal is much less Contrast enhancement is beneficial for many other pathologies expansive . In some cases, knowledge of distinctive features can such us infection, sprains, fibromas, capsular tears, adventitial lead to a specific diagnosis . After review of this exhibit, the view- bursitis, tumors, and foreign bodies . er will gain a firm appreciation of the common and uncommon lesions of the foot and ankle that result in decreased T2 signal intensity on MRI .

276 El e c t r o n i c Ex h i b i t s : Musculoskeletal

E299. MRI Spectrum of Soft Tissue Changes in the Diabetic Materials and Methods: Fifty patients aged 19 to 65 underwent Foot (CME Credit Available) MRI at 1 5T. before and after the intravenous administration of Pierre-Jerome, C.1,2; Albastaki, U.1; Kkarala, A.2; Gothlin, J.1; 0 .1mmol/kg of gadolinium-DTPA, with total volume of injection Terk, M.2; Moncayo, V. 2 1. Sahlgrenska-Molndal University ranging from 8 to 20 cc . Regions of interest in the area of pathol- Hospital, Gothenborg, Sweden; 2. Emory University Hospital, ogy were obtained prior to injection, scanning began 30 seconds Atlanta, GA after injection, and three minutes after injection, respectively . In Address correspondence to C. Pierre-Jerome (cpierrejerome@msn. each case, all imaging sequences were reviewed and the area of com) highest signal intensity on the delayed postcontrast images were measured with the average of three elliptical regions of interest . Background Information: The incidence of diabetes mellitus The corresponding areas of pathology on early postcontrast and has tremendously increased in the last decade . Complications precontrast imaging planes were identified and the signal intensi- can arise at any age, as the disease affects several systems in the ties were measured in identical fashion . The average of two body . Its predilection for the appendicular skeleton, especially the measurements was used to assess background noise signal lower extremity, is well known . Radiologists are most familiar intensity . Congruence of imaging planes was confirmed by using with the bony changes seen in the diabetic foot, but the damag- anatomic landmarks as well as external markers, when available . es to the soft tissues still remain a dilemma due to their multi- plicity and unpredictability . The purpose of this exhibit is Results: Postcontrast scans showed mean enhancement of 69% to present the myriad of soft tissues changes in the diabetic foot early and 90% late . Delayed postcontrast scans showed an aver- visualized on MR images . age of 21% greater enhancement than early post contrast scans, with a standard deviation of 13% . In 42% of cases, delayed scan- Educational Goals/Teaching Points: The goals are to present a ning showed at least 50% greater enhancement than early scans bilateral MR imaging protocol for the diabetic foot; systematically and in 18% of cases, twice the enhancement of early scans . review the soft tissues changes taking place in the diabetic foot at different stages of the disease; emphasize the use of gradient Conclusion: We conclude that MR imaging of the foot and ankle echo sequences with water excitation to evaluate the cartilage, three minutes after contrast injection shows significantly and discuss the criteria for using intravenous contrast in patients increased enhancement when compared to imaging 30 seconds with advanced disease . after injection . This greater intensity of enhancement may improve the detection and characterization of enhancing patho- Key Anatomic/Physiologic Issues and Imaging Findings/ logic conditions of the foot and ankle . Techniques: The soft tissues changes seen in the diabetic foot are: 1) tendenopathy (tendinosis, tendenitis, tendon tear), 2) myopathy (myositis, muscle ischemia, muscle necrosis), 3) liga- E301. Lisfranc Fracture-Dislocation: Imaging Findings With ment pathology (substance edema, tear), 4) bursa pathology Intraoperative Correlation and Postoperative Imaging (bursitis), 5) synovial changes (synovitis), 6) fascia changes (fas- Follow-Up ciitis), 7) subcutaneous fat changes (cellulitis, necrosis), 8) chon- Chakarun, C.; Tumyan, L.; Wolfson, N.; White, E.; Forrester, D. dropathy (chondral lesions) . University of Southern California, Los Angeles, CA Address correspondence to C. Chakarun ([email protected]) Conclusion: This exhibit presents a large spectrum of soft tissue changes in the diabetic foot . It is still not clear whether the diver- Background Information: Our purpose is to demonstrate the sity of these changes reflects the severity of the disease or not . plain radiography, CT and MR imaging findings in cases of Also, further research is needed to determine the clinical signifi- Lisfranc fracture-dislocation, and to correlate with intraoperative cance of these changes in predicting the evolution of the deform- photographs and surgical reports . ity of the foot . Educational Goals/Teaching Points: Lisfranc fracture-disloca- tion is a commonly overlooked diagnosis often due to the subtle- E300. Comparison of Early and Delayed Postcontrast MR ty of findings on plain radiographs . Missed diagnosis can result in Imaging for the Detection of Foot and Ankle Pathology significant morbidity . An understanding of the normal Lisfranc Shin, P.; Kier, R. Bridgeport Hospital, Bridgeport, CT joint is important in determining abnormalities and making the Address correspondence to P. Shin ([email protected]) correct diagnosis . Herein, we present cases of Lisfranc fracture- dislocation from our institution, some of which were initially Objective: MRI of the forefoot is sometimes performed after the overlooked . Through our exhibit, the reader will become familiar administration of gadolinium-based contrast agents as an with the imaging findings on plain radiography CT, and MRI cor- attempt to improve detection or characterization of various foot related with intraoperative photographs and surgical reports . pathology . In certain cases, some pathology may not be fully vis- ualized with only early postcontrast imaging . Delayed imaging Key Anatomic/Physiologic Issues and Imaging Findings/ after three minutes may improve detection and characterization Techniques: The Lisfranc ligament forms an oblique connection of both osseous and soft tissue abnormalities in the forefoot . This between the first cuneiform and the base of the second metatar- study was designed to determine whether 30 second or three sal . Diastasis between the first and second metatarsals is the minute delay after contrast injection was superior for demon- main finding, however, without stress views this can be subtle . If strating enhancement in pathologic tissue . the patient is unable to bear weight on both feet for stress views, CT imaging is recommended . Other imaging findings include shear fracture at the second metatarsal, and impaction fractures of the navicular, cuboid, and medial cuneiform . Lisfranc fracture-

277 El e c t r o n i c Ex h i b i t s : Musculoskeletal dislocation usually results from crush injury or high energy trau- modalities such as conventional radiographs and MR will be ma . Missed diagnosis often leads to significant morbidity . included where complementary . Nondisplaced injuries can be treated with cast immobilization, and unstable injuries are treated by open reduction and internal Educational Goals/Teaching Points: The objectives of this edu- fixation . cational activity are for the participant to learn complex ankle and foot anatomy utilizing interactive 3D models; learn fracture pat- Conclusion: The imaging findings of Lisfranc fracture-dislocation terns and mechanisms of injury in foot and ankle fractures; can be subtle, and suspicion warrants stress views or further develop a systematic method for interpreting diagnostic images evaluation by CT or MRI . Through examples from our institution, of foot and ankle trauma, and understand postoperative imaging the reader will become familiar with these imaging findings cor- evaluation . related with intraoperative photographs and surgical reports . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The interactive 3D images will be used for demon- E302. My Foot Hurts Doc... What Do You Think? stration of normal anatomy . Models of various ankle and foot Mazzie, J.1; Smith, S.2; Scalcione, L.1; Katz, D.1; Grossman, M.1; injuries will be presented illustrating mechanisms of injury of the Luchs, J.1 1. Winthrop-University Hospital, Mineola, NY; 2. foot and ankle . University of Maryland, Baltimore, MD Address correspondence to D. Katz ([email protected]) Conclusion: Interactive 3D reformations of the foot and ankle are useful in teaching anatomy and pathology of the injured foot Background Information: Foot pain is a common clinical com- and ankle to medical students, residents and practicing radiolo- plaint heard by our orthopedic and podiatric colleagues, and by gists . primary care physicians . The purpose of this exhibit is to present the imaging findings of a wide range of traumatic and non-trau- matic conditions which can cause foot pain . E304. The Lateral Ankle: What is There and What Can Go Wrong (CME Credit Available) Educational Goals/Teaching Points: Common traumatic frac- Doshi, S.; Edwards, A. William Beaumont Hospital, Royal Oak, MI tures such as Jones fracture, Lisfranc injury, talar neck fracture, Address correspondence to A. Edwards ([email protected]) and calcaneal fractures will be shown and discussed, as well as infectious processes, neuropathic disease, and overuse injuries . Background Information: Lateral ankle pain related to both Additionally, chronic causes of foot pain, including plantar fibro- chronic etiologies and acute injury account for a significant mas, plantar spurs, osteochondral lesions within the talus, and number of emergency room, primary care, and orthopedic visits . osteonecrosis (i .e . Frieberg’s necrosis) will be shown and dis- MRI can play a vital part in determining the etiology and plan- cussed . Painful conditions associated with foot ossicles will also ning the treatment, surgical or conservative, of lateral ankle be briefly covered (i .e ., sesamoiditis) . pathology . Advances in technology and improved access to MRI have resulted in its increased utilization . The purpose of this Key Anatomic/Physiologic Issues and Imaging Findings/ exhibit is to create familiarity and comfort with MRI evaluation of Techniques: Radiographs, ultrasound, CT, MR, and nuclear medi- the lateral ankle with respect to the relevant anatomy and types cine imaging will be shown and the relevant literature reviewed . of pathology .

Conclusion: Foot pain is a common clinical complaint heard by Educational Goals/Teaching Points: The goals are to define our clinical colleagues in orthopedic and podiatric medicine as the lateral ankle for the purpose of this educational exhibit; well as in primary care . A wide range of traumatic and nontrau- review relevant MRI anatomy; discuss common and less com- matic conditions can cause foot pain, which may be identified on mon types of pathology; detail the primary and secondary MRI imaging studies . Following review of this exhibit, the radiologist findings related to various types of pathology, and relate mecha- should have a concise knowledge of the imaging appearances of nism of injury . entities which may cause foot pain . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: In order to diagnose the etiology of lateral ankle E303. Interactive 3D CT for Teaching Anatomy and Pathology pain, one must be familiar with the structures and mechanics . in Complex Foot and Ankle Trauma (CME Credit Available) Pathology related to the tendons, such as tendinosis, tenosynovi- Goodman, M.; Richardson, M.; Bush, L.; Mulcahy, H.; Chew, F. tis, various types of tears, subluxation, and dislocation, is relative- University of Washington, Seattle, WA ly common and can be readily evaluated with MRI . Additionally, Address correspondence to M. Goodman (goodmm@ the pathology related to the ligaments, such as mild or moderate u.washington.edu) sprains as well as complete tears, is also relatively common and can be readily evaluated with MRI . MRI also provides osseous Background Information: Early recognition and treatment of structural detail and increases sensitivity for detecting bone mar- foot and ankle problems are imperative for avoiding associated row edema and radiographically occult fractures . Although a morbidities . The ankle represents an anatomically complex region diagnosis of anterolateral impingement syndrome, nerve entrap- that can be quite challenging . We present an interactive compu- ment, or tendon entrapment can be determined after a thorough ter exhibit to demonstrate the utility of interactive 3D reconstruc- , MRI can serve as an invaluable noninvasive tions in the preoperative evaluation of complex ankle and foot tool if there is an understanding of the anatomy and symptoma- trauma . This will help the user understand not only normal anat- tology . omy, but also fracture patterns and mechanism of injury . Other

278 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Conclusion: With the excellent spatial resolution, soft tissue con- Key Anatomic/Physiologic Issues and Imaging Findings/ trast, and improved field strength of newer MRI units, the lateral Techniques: The exhibit will include MRI evaluation of normal ankle can be thoroughly evaluated for the various etiologies of and abnormal peroneal tendons, peroneal retinacula and Os per- lateral ankle pain . In addition to allowing excellent visualization oneum . of the tendons, ligaments, and nerves, MRI readily provides osseous structural and bone marrow detail . Although the lateral Conclusion: It is important for the radiologist to understand nor- ankle consists of a well defined and anatomically confined space, mal peroneal tendon anatomy and key MR imaging features of there is a wide variety of etiologies for both acute and chronic various pathologies and associated syndromes . The differentia- lateral ankle pain . We hope that this exhibit will provide a high tion between such lesions is useful to direct appropriate patient yield and simplified approach for the evaluation of the lateral management . ankle anatomy and pathology .

E307. Deltoid Ligament: MRI Evaluation E305. Painful Ankle Syndromes – MRI Evaluation (CME Chhabra, A.1; Carrino, J.1;Batra K.2,3; 1. Johns Hopkins, Credit Available) Baltimore, MD; 2. Drexel, Philadelphia, PA; 3. University of Texas Chhabra A.1; Yadav, S.2; Carrino, J. 1 1. Johns Hopkins, Medical Branch, Galveston, TX Baltimore, MD; 2. Dr RML Hospital,Delhi, India; Address correspondence to A. Chhabra (avneesh.chhabra@ Address correspondence to A. Chhabra (avneesh.chhabra@ yahoo.com) yahoo.com) Background Information: Deltoid ligament injuries are com- Background Information: Painful ankle syndromes have a monly missed on ankle MR evaluation . Partial tears and sprains broad differential based on clinical evaluation . MRI provides excel- are more common than complete tears . We will present a spec- lent depiction of the abnormality and the underlying etiology . trum of deltoid ligament abnormalities in this exhibit .

Educational Goals/Teaching Points: The exhibit viewer will Educational Goals/Teaching Points: The exhibit viewer will learn optimal ankle MR technique for musculotendinous and lig- learn optimal ankle MR techniques for ankle ligament evaluation; ament evaluation; gain knowledge of various painful ankle syn- gain knowledge of MR anatomy of various components of super- dromes, such as, painful os peroneum syndrome, painful os ficial and deep deltoid ligament with case examples, and become naviculare syndrome, Os Trigonum syndrome, Haglund’s syn- familiar with various pathologies, such as partial tear, complete drome, Henry’s knot syndrome, sinus tarsi syndrome, tarsal tun- tear, secondary degenerative changes, ganglion formation antero- nel syndrome and ankle impingement syndromes, and become medial and posteromedial impingement and association with familiar with key MR imaging features of these syndromes . spring ligament pathology .

Key Anatomic/Physiologic Issues and Imaging Findings/ Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The exhibit will address the painful accessory ossi- Techniques: The goal is for exhibit viewer to learn various com- cles and evaluate other anatomic confined spaces of ankle where ponents of superficial and deep portions of deltoid ligament and abnormalities leading to painful ankle can be detected on MRI . their abnormalities .

Conclusion: MRI is an excellent tool to evaluate painful ankle Conclusion: It is important for the imager to recognize the del- syndromes . The differentiation between these lesions is impor- toid ligament abnormalities for early management and preven- tant to direct appropriate patient management . tion of long term morbidity .

E306. MR Evaluation of Peroneal Tendon Pathology E308. MRI of the Achilles Tendon: Normal Anatomy, Pitfalls Chhabra, A.1; Sayed, A.2; Carrino, J. 1 1. Johns Hopkins, and Common Pathology Baltimore, MD; 2. Temple University Hospital, Philadelphia, PA; 3. Pierre-Jerome, C.1; Albastaki, U.1; Gothlin, J.1; Terk, M.2 1. Address correspondence to A. Chhabra (avneesh.chhabra@ Sahlgrenska University Hospital, Molndal, Sweden; 2. Emory yahoo.com) University Hospital, Atlanta, GA Address correspondence to U. Albastaki ([email protected]) Background Information: Peroneal tendon pathology is a com- mon problem . MR imaging depicts various abnormalities related Background Information: The Achilles tendon is named after to peroneal tendons and peroneal retinacula in an exquisite the Greek hero Akhilleus whose damage to the tendon lead to manner . his fatal apprehension . The tendon runs from the musculotendi- nous junction of the gastrocnemius muscle to the bony cortex of Educational Goals/Teaching Points: The viewer of this exhibit the calcaneus . Contrarily to most tendons, the Achilles tendon will learn optimal MR technique for evaluation of peroneal ten- does not cross over the joint space to reach its insertion point; dons; gain knowledge of normal MRI anatomy of peroneal ten- but it runs posterior to the ankle joint . The Achilles tendinopaties, dons and associated variations with case examples, and become if not properly diagnosed and managed, can carry serious clinical familiar with MRI appearances of various pathologies, such as and biomechanical consequences leading to disability . This longitudinal split tears, complete tears, tendon dislocations, teno- exhibit will present the MR characteristics of the normal Achilles synovitis, deficient and abnormal peroneal retinacula, and painful tendon and imaging pitfalls, and present the common patholo- Os peroneum syndrome . gies of the Achilles tendon as seeing on MRI .

279 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Materials and Methods: The materials are from the radiological Conclusion: Knowledge of the anatomy and pathology frequent- archives of Emory University and Sahlgrenska University . The MR ly encountered in conjunction with improved understanding of images of the lower leg and ankle joint are reviewed . The imag- the clinical features can aid in accurate diagnosis of impingement ing protocols from the two institutions are fairly similar for most syndromes at the ankle and hindfoot . examinations . The imaging sequences include: SET1W sagittal and coronal, STIR sagittal and STIR axial . The normal anatomy of the tendon is analysed from images of the lower leg and ankle E310. MRI of Baxter’s Nerve: Anatomy, Variations and from three asymptomatic volunteers . First, we study the normal Pathology configuration–shape, size, signal intensity, origin and insertion of Brooks-Sienkiewicz, S.1; Morrison, W.1; Zoga, A.1; Elias, I.2; the normal tendon . Secondly, we review images of patients with Carneiro, C.3 1. Thomas Jefferson University Hospital, Havertown, different pathologies of the tendon and pathologies of the sur- PA; 2. Rothman Institute, Philadelphia, PA; 3. No Institutional roundings tissues affecting the tendon . The findings are classified Affiliation into two groups: nonoperative tendinopaties and operative Address correspondence to S. Brooks-Sienkiewicz (sara.brooks- changes of the tendon . [email protected])

Results: The normal anatomy of the Achilles tendon is illustrated Background Information: Baxter’s nerve, a branch of the poste- in three planes along with some pitfalls . The non-operative tendi- rior tibial nerve, supplies the plantar fascia and can be a source nopaties include: degenerative tendinosis, inflammatory tendoni- of chronic heel pain . tis, infectious tendonitis, partial tendon tear, full tendon tear, ten- donitis with bursitis, tenosynovitis, Achilles tendinopaties of the Educational Goals/Teaching Points: Knowlege of anatomy and diabetic foot associated with myositis and cellulitis . Of the oper- normal variation, and recognition of pathology of Baxter’s nerve ated tendon, we present the postoperative changes without tear (and the tarsal tunnel that it courses through) is important in and postoperative changes with re-tear . There is one case of patients with heel pain . transplanted tendon with re-tear . Key Anatomic/Physiologic Issues and Imaging Findings/ Educational Goals/Teaching Points: The goals are to review Techniques: Baxter’s nerve courses through the tarsal tunnel and the normal anatomy of the tendon, and to have a comprehensive can be affected by pathology within it . understanding of the tendon’s pathology . Conclusion: This exhibit will depict the range of findings seen on Conclusion: This exhibit presents a didactic review of the anato- MRI . my and pathologies of the Achilles tendon .

E311. Multimodality Imaging of Calcaneal Lesions (CME E309. Impingement Syndromes of the Ankle and Hindfoot: A Credit Available) Case-Based Review Motamedi, D.1; Young, S.1; Bauer, A.2; Modarresi, S. 3; Dym, J.1; Zbojniewicz, A.; Nguyen, T.; Mace, A. West Virginia University, Learch,T.1 1. Cedars-Sinai Medical Center, Los Angeles, CA; 2. No Morgantown, WV Institutional Affiliation; 3. West Los Angeles Wadsworth VA Address correspondence to A. Zbojniewicz ([email protected]) Medical Center Address correspondence to D. Motamedi ([email protected]) Background Information: Impingement syndromes of the ankle and hindfoot are a well recognized cause of chronic pain . Background Information: The purpose of this exhibit is to Understanding the clinical features, pathophysiology, and expect- review various usual and unusual cases of calcaneal pain; pro- ed imaging features can improve the accuracy of reports and aid vide a multimodality pictorial presentation of various entities in clinical management of patients . affecting the calcaneus, and delineate a practical approach to dif- ferential diagnosis of calcaneal abnormalities . Educational Goals/Teaching Points: The goal of this presenta- tion is to review the anatomy and pathology of the ankle joint Educational Goals/Teaching Points: The exhibit will include an and hindfoot, which may contribute to development of impinge- overview of various usual and unusual causes of calcaneal pain ment . The presentation will consist of a brief review of the clini- on plain film, CT, and MRI; a review of imaging findings with cal features and anatomy, including normal variations that may emphasis on pattern-based approach to differential diagnosis, contribute to impingement, followed by reinforcement by multi- and sample cases (including coalition, Haglund’s deformity, stress ple case presentations . fracture, lover’s fracture, diabetic ankylosis, rheumatoid arthritis, reactive arthritis, gout, retrocalcaneal bursitis, osteomyelitis, uni- Key Anatomic/Physiologic Issues and Imaging Findings/ cameral bone cyst, intraosseous lipoma, osteoid osteoma, giant Techniques: Impingement syndromes can be divided based on cell tumor, and metastases) . location and include anterior, anterolateral, and posterior impingement as well as impingement at the sinus tarsi . Multiple Key Anatomic/Physiologic Issues and Imaging Findings/ imaging modalities including MRI, CT, SPECT-CT and plain radiog- Techniques: The exhibit will prove an anatomic review of the raphy can be useful in conjunction with the clinical history to aid calcaneus and common normal variants; a physiological review in diagnosis . of calcaneal vascularity, articulations, and stress distribution, and a multimodality review of various usual and unusual pathologic entities affecting the calcaneus .

280 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Conclusion: After reviewing this exhibit, radiologists will identify E313. Down at the Heel: The Radiology of Calcaneal Injuries various causes of calcaneal pain seen on plain film, CT, and MR Carr, R.; Nett, M.; Sadro, C.; Chew, F. University of Washington, imaging and provide valid differential diagnosis using a pattern- Seattle, WA based approach; recognize the appearance and expected distri- Address correspondence to F. Chew ([email protected]) bution of calcaneal lesions and fractures to aid in the evaluation of challenging cases, and understand the importance of recom- Background Information: Injuries of the calcaneus occur mending appropriate cross-sectional imaging such as MRI in through a variety of mechanisms and may range in radiologic appropriate cases for further evaluation or biopsy planning . conspicuity from the obvious to the truly occult . Some fractures are devastating in their sequelae, while others may progress to functional recovery following proper treatment . The radiologist E312. Calcaneus Fracture: What Should the Radiologist should be able to detect and fully characterize these injuries in Communicate to the Referring Clinician? (CME Credit order to optimize patient care . Available) Bodiwala, R.; West, O.; Kumaravel, M. University of Texas Health Educational Goals/Teaching Points: Following the completion Science Center at Houston, Houston, TX of this educational activity participants should be able to discuss Address correspondence to R. Bodiwala (ravibodiwala@gmail. the normal imaging anatomy of the calcaneus and its articula- com) tions; recognize and distinguish among the various types of cal- caneal injuries and their mechanisms, and summarize the typical Background Information: Calcaneus is the most commonly treatment and outcome of various calcaneal injuries . fractured tarsal bone, accounting for 2% of overall fractures and 60% of major tarsal injuries . The aim of this exhibit is to review Key Anatomic/Physiologic Issues and Imaging Findings/ the anatomy of the calcaneus, describe the pathomechanics of Techniques: Emphasis is placed on the normal calcaneal anato- calcaneal injury, enlist the common and uncommon fracture pat- my, common and uncommon injury patterns, epidemiology, terns, and to provide the radiologist with knowledge of certain treatment, and expected outcomes . The appropriate use of radi- key fracture characteristics that have significant prognostic impli- ography, CT, and MRI is discussed . cations . In achieving this purpose, we will use images acquired using conventional radiography, CT, MRI, and 3D volume render- Conclusion: Calcaneal injuries are common and accurate detec- ings . tion and full characterization is imperative for appropriate man- agement . Understanding the surgical treatment of these injuries Educational Goals/Teaching Points: The presentation is in a will allow the radiologist to detect complications . case-based format . Multiple cases are presented that describe the calcaneal fracture patterns, for example, intra-articular, extra-artic- ular, joint depression type, and tongue fracture type . Sanders’ E314. The “Dreaded Black Line” and Other Stress Fractures and Munichs CT classification of calcaneal fractures will also be of the Tibia reviewed . We will also discuss management of these different Manzoul, S.; Brindle, K. George Washington University, Bethesda, fracture patterns, as well as potential complications . MD Address correspondence to K. Brindle ([email protected]) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The calcaneus has three articulating surfaces with Background Information: The tibia is one of the most common the talus, namely the anterior facet, middle facet, and the posteri- locations of stress fractures . Occurring in runners and other ath- or facet . The fourth calcaneal articulating surface is between the letes, stress fractures of the tibia are seen most frequently at the calcaneus and cuboid . We will use 3D volume rendered images posteromedial cortex of the proximal to mid tibial shaft . Tibial to depict the normal calcaneal anatomy . Most calcaneal fractures stress fractures though can, in fact, occur anywhere along the result from axial loading, which produces compression and shear tibia . They can also be of the insufficiency type . One unusual type fracture lines . We will illustrate these fracture lines using stress fracture that is commonly missed occurs along the anterior graphics . cortex of the tibia . It is frequently multiple and can be bilateral . Called the “dreaded black line” by some, the term refers to the Conclusion: Sanders’ and Munichs CT classification of calcaneal propensity for delayed healing and associated complications . fractures has provided a road map for a consensus in reporting X-ray evaluation of stress fractures is usually negative early on . calcaneal injuries, and has been helpful in planning treatment The diagnosis can be made at this stage with radionuclide bone and determining prognosis . Continued advancement in CT and scan, MRI or sometimes CT scan . Radiographs typically become MR technology has enabled the radiologist to provide the refer- positive after several weeks . ring clinician with key knowledge to avoid certain management pitfalls . For instance, injury to the peroneal tendon or the neurov- Educational Goals/Teaching Points: It is the goal of this exhibit ascular bundle that runs along the medial border of the cal- to review the radiologic findings of tibial stress fractures . Because caneus may occur directly from trauma, or as an unintended con- their location and imaging appearance can vary and findings are sequence of fracture reduction . The radiologist should play an typically subtle, they can be easily overlooked or mistaken for important role in not only diagnosing these injuries, but also other pathology . The clinical features, radiographic findings, and forewarning the treating clinician about the possibility of these follow-up of the “dreaded black line” type stress fracture will be injuries . emphasized but other types of tibial stress fractures will be dis- cussed . The focus will be on x-ray analysis, but radionuclide bone scan, MRI, and CT features of stress fractures will also be addressed .

281 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: In this pilot investigation, we found that 256-MDCT Techniques: Radiographically, tibial stress fractures can present dynamic-kinematic imaging adequately depicted by subjective as cortical thickening, periosteal reaction, or a linear band of scle- visualization real time unconstrained joint motion of the knee rosis . A fracture line may or may not be present . When seen, the and wrist bilaterally from a single acquisition . We chose the knee fracture line can be horizontal or vertical . A bone scan will dem- joint because patellofemoral maltracking is a common disorder . onstrate focal increased uptake of radiotracer at the site of the We choose the wrist because it is a complex joint with multiple fracture and can be used to distinguish them from shin splints . small articulations and degrees of freedom with subtle ranges of Bone marrow edema, periosteal edema, and a fracture line are motion . 256-MDCT may be useful in diagnosing patellar tracking findings that can be seen on MRI . CT findings include endosteal disorders and instabilities of the distal radioulnar joint (DRUJ) . and periosteal reaction as well as a lucent fracture line through the cortex of the bone . E316. Patterns and Significance of Bone Marrow Edema in Conclusion: The variable and often subtle findings of fatigue and the Knee: A Case Based Review insufficiency type tibial stress fractures will be reviewed . The Nicola, R.1; Dheer, S.2; Zoga, A.3; Morrison, W.3 1.University of review will encompass the unique features of stress fractures of Medicine and Dentistry of New Jersey-Robert Wood Johnson the anterior tibial cortex including clinical presentation and out- Medical School, Cooper University Hospital, Camden, NJ; 2. South come . Jersey Regional Medical Center, Cherry Hill, NJ; 3. Thomas Jefferson University Hospital, Philadelphia, PA Address correspondence to S. Dheer ([email protected]) E315. Functional Joint Imaging Using 256-Detector Row CT: Technical Feasibility (CME Credit Available) Background Information: MRI studies are a mainstay in the Kalia, V.1; Obray, R.2; Filice, R.2; Fayad, L.2; Murphy, K.2; Carrino, diagnosis and management of common musculoskeletal disor- J.2 1. Johns Hopkins University School of Medicine, Baltimore, ders affecting the knee . It is important for the radiologist and MD; 2. Johns Hopkins University Medical Center, Baltimore, MD treating physician to recognize various patterns of disease and Address correspondence to V. Kalia ([email protected]) their significance on knee MRI’s .

Objective: Musculoskeletal functional imaging should encom- Educational Goals/Teaching Points: The goals are to inform pass the real-time (dynamic) depiction of joints in motion (kine- and review with participants the patterns and significance of matic) . Our goal was to determine the technical feasibility of per- bone marrow edema encountered on MRI examinations of the forming dynamic-kinematic imaging of the knee and wrist joints knee . This will be done in an interactive, case review format . using a new modality, 256-slice MDCT . Key Anatomic/Physiologic Issues and Imaging Findings/ Materials and Methods: After informed consent was obtained, Techniques: Specific cases to be shown include: pivot shift injury six adult nonpregnant volunteer subjects were enrolled for 256- with anterior cruciate ligament tear, transient patellar dislocation, detector row CT imaging of the knee and wrist, with three sub- occult fracture, osteochondral fracture, subenthesial marrow jects allocated to bilateral knee imaging for patellofemoral evalu- edema in the setting of quadriceps and patellar tendinosis/tears, ation (n=6 knees) and three subjects allocated to bilateral wrist reactive edema as a sign of meniscal tear, femoral and tibial imaging for supination-pronation (n=6 wrists) and radioulnar subchondral insufficiency fractures (formerly referred to as spon- deviation (n=6 wrists) . Participants had no history of joint pathol- taneous osteonecrosis of the knee/tibia) and osteomyelitis . ogy or surgery in the examined joints . All examinations were per- formed using a prototype FDA approved 256-multidetector row Conclusion: Following the conclusion of this activity, the partici- CT (Toshiba Medical Systems, Tochigi-ken, Japan) . The x-ray pant should have a better understanding of the various patterns detector is composed of 256 x 0 .5 mm detectors delivering 12 .8 of bone marrow edema encountered on knee MRI’s, any associ- cm of coverage in the z-axis . A single rotation of the detector ated injuries and the prognostic significance of various injury pat- takes 0 .5 seconds . Image acquisition time was 10 seconds for terns . each volume . 2D multiplanar reformations, 3D surface shaded, volume rendered, and 4D cine loop images were reconstructed from the source data . E317. MRI of Cystic Lesions In and Around the Knee Lien, L. 1; August, D. 1; Santa Maria, J. 1; Burns, J.; Hunter, J. 2; Results: No device malfunctions or complications occurred . Knee Tehranzadeh, J. 1 1. University of California-Irvine, Orange, CA; cine images showed normal translation of the patella from multi- 2. Lawrence J. Ellison Ambulatory Care Center, Sacramento, CA ple angles and the extensor mechanism tendons throughout Address correspondence to L. Lien ([email protected]) knee flexion . Regarding radioulnar deviation, wrist cine images showed normal “fluid-like” movement of the carpus at multiple Background Information: Cystic lesions are common in knee angles and positions of associated soft tissues throughout the joint MR interpretation which include bursa, ganglion cyst, menis- range of motion . Regarding pronation/supination, wrist cine cal cyst, abscess, cystic neoplasm, and cystic adventitial disease images showed normal rotation of the radius with respect to the of the artery, etc . It is important to be familiar with MR appear- ulna and positions of associated soft tissues throughout the ance of these lesions to avoid unnecessary surgery and guide range of motion . The alignment of the carpus and the distal radi- appropriate treatment . oulnar joint were well depicted and qualitatively showed normal motion without an instability pattern . Educational Goals/Teaching Points: The goal is to review com- mon and less common cystic lesions in/around the knee joint and the characteristic MR imaging findings .

282 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Key Anatomic/Physiologic Issues and Imaging Findings/ E319. Neoplastic Disease About the Knee: Techniques: Imaging classification is as follows: 1 . Radiologic-Pathologic Correlation Compartment: intracapsular vs . extracapsular . 2 . Location: anteri- Zbojniewicz, A.; Nguyen, T.; Mace, A.; Wilks, K.; Ward, J. West or, medial, lateral, and posterior . 3 . Related Anatomic Structure: Virginia University, Morgantown, WV bursa, ganglion, cruciate ligament, meniscus, bone, proximal tibi- Address correspondence to A. Zbojniewicz ([email protected]) ofibular joint, peroneal nerve, and popliteal artery . 4 . Pathologic Nature: neoplastic vs . non-neoplastic . Background Information: Imaging of the knee, primarily MRI, is performed frequently and on a daily basis in most imaging cent- Conclusion: The current exhibit will review the MR appearance ers . This exhibit aims to review both common and uncommon of common and less common cystic lesions of the knee based neoplastic disease encountered while imaging the knee with on anatomic compartment, location, related anatomic structures, illustration using multiple modalities and pathologic correlation . and pathologic nature . Educational Goals/Teaching Points: The goal of this exhibit is to provide an improved ability to describe, characterize and diag- E318. Imaging of Meniscal Tear and Cartilage Damage at nose neoplastic disease that may be encountered when imaging 1.5T, 3T, and 7T the knee . Sammet, S.1; Wassenaar, P.1; Zalewski, S.2; Stoez, M.2; Knopp, M.1 1. The Ohio State University, Columbus, OH; 2. Philips Key Anatomic/Physiologic Issues and Imaging Findings/ Medical Systems, Highland Heights, OH Techniques: Neoplastic disease about the knee can occur both Address correspondence to S. Sammet ([email protected]) within the bones as well as in extraskeletal soft tissues including within the joint and the surrounding soft tissues . Discussion of Objective: Meniscal injuries and cartilage abnormalities are often pathology will be divided into these three areas with emphasis difficult to diagnose in MRI at conventional field strengths due to on differential diagnoses, key imaging features, and pathologic their small sizes and low contrast . Imaging may benefit from high correlation with the aim to improve understanding of the imag- signal to noise ratios and contrast mechanisms at ultra high field ing appearances . strengths . The objective of this study was to compare image quality of a knee injury at 1 .5T, 3T, and 7T based on contrast and Conclusion: Neoplastic disease about the knee may be encoun- artifacts . tered more frequently than expected given the large number of knee MRIs performed in daily practice . This exhibit allows the Materials and Methods: Four healthy volunteers (age 25-32 interpreting radiologist increased confidence in interpreting these years old) and one patient with a known meniscal tear (51 year findings when something other than the expected sports medi- old male) were imaged at 1 .5T, 3T, and 7T (Philips Healthcare, cine diagnoses are encountered . Cleveland, OH) using 8-channel knee coils . The subjects were scanned in a prone position with their knee in dedicated knee coils at similar positions relative to the coil walls . MR sequences E320. Relationship Between Medial Femoral Condyle were optimized at 7T on the healthy volunteers, after which Osteochondral Defects and Tibial Spine Morphology imaging was performed on the patient with the meniscal tear Brooks-Sienkiewicz, S.1; Morrison, W.1; Zoga, A.1; Carneiro, C.2 1. across all field strengths using the same protocol . Images were Thomas Jefferson University Hospital, Philadelphia, PA; 2. No acquired in both sagittal and coronal planes, using a turbo spin Institutional Affiliation echo sequence (TSE), both with and without fat saturation . The Address correspondence to S. Brooks-Sienkiewicz (sara.brooks- sequences used repetition time/echo time=3,000/25 millisec- [email protected]) onds, echo train lengths 13, with an inplane resolution of 0 .3 x 0 .3mm2 and a slice thickness of 2 .5 mm . Objective: The objective is to evaluate whether there is an asso- ciation between tibial spine morphology and osteochondral Results: In a patient with a knee injury a meniscal tear could be defects (OCDs) at the medial femoral condyle . identified in the same anatomical location on coronal MR-images acquired at 1 5T,. 3T and 7T . Fat saturation did not Materials and Methods: MRI of 29 knees with OCDs at the add to the visualization of the injury . An increase in contrast of medial femoral condyle were evaluated by two musculoskeletal cartilage signal compared to that of surrounding tissue can be radiologists . This group included nine patients with healed OCDs . seen at 7T . This increase aids in the depiction of the lesion in the The size and morphology of the medial tibial spine were noted, meniscus, as well as potential cartilage damage . A stronger sus- assessed on coronal images at midline and at the center of the ceptibility effect can be observed as hypointense regions at the OCD . Size was evaluated relative to lateral spine size intersection of cartilage and cortical bone . A slight shift in the (medial:lateral) with categories including 1:>1 (I), 1:1 (II), 1-2:1 cartilage signal causes the susceptibility effects to be less visible (III), and >2:1 (IV) . Absolute medial tibial spine height was meas- caudal to the joint . ured at the midline with respect to the tibial plateau . Morphology was evaluated as pointed (I), round (II), partial facet (III), and Conclusion: At ultra high field strengths (7T), a higher contrast is complete facet (IV) . These findings were compared with 29 MRI produced in the meniscus and knee cartilage compared to lower knees of age-matched patients without OCDs . Comparison was field strengths . This contrast not only allows better depiction of also made between healed and nonhealed OCDs . meniscal tears, but is promising in the depiction of cartilage damage in human knees . Results: In the OCD group, 3% of patients had type I size, 14% type II, 24% type III, and 59% type IV . Morphology in the OCD group included 28% type I, 28% type II, 24% type III, and 21% type IV . In the healed OCD subset, 11% of patients had type I 283 El e c t r o n i c Ex h i b i t s : Musculoskeletal size, 22% type II, 33% type III, and 33% type IV . Morphology in E322. Bisphosphonate-Related Femoral Insufficiency the healed subset included 33% type I, 22% type II, 22% type III, Fractures and 22% type IV . In the control group, 0% of patients had type I Bush, L.; Chew, F.; Richardson, M., Ott, S.; Goodman, M.; Mulcahy, size, 7% type II, 34% type III, and 59% type IV . Morphology in H. University of Washington, Seattle, WA the control group included 24% type I, 10% type II, 66% type III, Address correspondence to L. Bush ([email protected]) and 10% type IV . Average tibial spine height measured 8 4. mm in the OCD group, 9 .4 mm in the healed subset, and 7 .8 mm in Background Information: Osteoporosis, metabolic conditions the controls . There was no significant difference in any of the that predispose to low energy fractures, and lytic metastases are parameters measured . important indications for the administration of bisphosphonate . Bisphosphonates increase bone mineral density by Conclusion: There is no evidence of an association between decreasing osteoclast activity . It is well documented that medial femoral condyle OCDs and tibial spine morphology . There bisphosphonates reduce fracture morbidity and mortality, and is also no difference in tibial spine characteristics in healed and they are widely used . Ironically the very mechanism by which nonhealed OCDs . these medications suppress osteoclast activity can adversely affect normal bone remodeling . Recent literature demonstrates a rare, but concerning, pattern of bisphosphonate-related femoral E321. The Spectrum of Chondral, Osteochondral and insufficiency fractures . Unresolved areas of microscopic damage Subchondral Abnormalities of the Knee may accumulate at critical sites of mechanical bending stress to Borzykowski, R.1,2; Friedman, S.1,2; Finkelstein, M.1,2; Thornhill, form an insufficiency fracture; particularly in the subtrochanteric B.1,2; Shi, A.1 1. Montefiore Medical Center, Bronx, NY; 2. Albert region of the proximal femoral shaft . These insufficiency fractures Einstein College of Medicine, Bronx, NY have a characteristic clinical presentation and imaging appear- Address correspondence to B. Thornhill ([email protected]) ance and can progress with minimal force into a complete, trans- verse, potentially life-threatening femoral shaft fracture . Background Information: The spectrum of abnormalities involv- ing the articular cartilage, the osteochondral junction and the Educational Goals/Teaching Points: After completing this edu- subchondral region of the knee includes injuries, degenerative cational activity the participant will be able to discuss the poten- changes, ischemic changes, tumor and infection . Awareness of tial for patients on bisphosphonate medications to develop fem- the importance of these abnormalities, the sometimes confusing oral insufficiency fractures; recognize the characteristic appear- nomenclature surrounding this area, and the radiographic and ance of bisphosphonate-related insufficiency fractures in multiple MRI appearances of the various lesions is essential for accurate modalities prior to fracture completion, and recommend expedi- diagnoses . ent intervention to reduce the life-threatening risk of fracture completion . Educational Goals/Teaching Points: The structure of cartilage and types of cartilage will be briefly reviewed . Acute and chronic Key Anatomic/Physiologic Issues and Imaging Findings/ chondral and osteochondral injuries will be explained and illus- Techniques: Normal biomechanics of bone remodeling requires trated . The importance of assessing the cartilage on all knee MRI a balance of osteoclast and osteoblast activity to respond to examinations will be stressed . Various subchondral abnormalities microscopic injury and mechanical stress . Bisphosphonate medi- including fractures, post-traumatic sequelae, degenerative chang- cations can overly suppress the osteoclast component of bone es and classic osteonecrosis will be included . The terminology remodeling allowing formation of insufficiency fractures at sites referable to these areas will be reviewed, including osteochon- of critical mechanical stress . We demonstrate these lesions with dral injury, osteochondrosis dissecans, and the misnomer of nuclear scintigraphy, radiography, CT, and MRI . “spontaneous” osteonecrosis, a term no longer thought to be accurate . Application of the various terms according to the age of Conclusion: This interactive computer-based educational exhibit the patient, presumed etiology and chronicity of the abnormali- presents a rare complication of bisphosphonate therapy with a ties will be included . characteristic imaging appearance . Radiologists who are aware of this entity and recognize the characteristic lesion of an insuffi- Key Anatomic/Physiologic Issues and Imaging Findings/ ciency fracture in this setting can alert and educate the referring Techniques: The histology of cartilage, the osteochondral junc- provider; thereby reducing the risk of life-threatening fracture tion and the subchondral bone will be illustrated using diagrams . completion in these patients . The abnormalities will be demonstrated using radiography and MRI . Commonly used MRI techniques available on a widespread The views expressed in this manuscript are those of the authors basis will be emphasized . and do not reflect the official policy or position of the Department of the Army, Department of Defense or the U.S. Conclusion: The viewer should come away from the exhibit with Government. an understanding of the various abnormalities of the articular and subarticular regions of the knee including etiologies, imaging appearances and terminology . The knowledge regarding these relatively common findings will be readily applicable to routine diagnostic studies .

284 El e c t r o n i c Ex h i b i t s : Musculoskeletal

E323. Femoral Head Fractures: Review of Imaging Features ment, and provide radiologists with the knowledge necessary for with a Focus on Management (CME Credit Available) accurate and rapid identification of these pathological processes . Spence, S.; Kumaravel, M. University of Texas Health Science Center at Houston, Houston, TX Educational Goals/Teaching Points: The iliopsoas compart- Address correspondence to S. Spence (Susanna.C.Spence@uth. ment acts as a mechanism of spread of pathology in the body . tmc.edu) Knowledge of its anatomy and the pathological processes that can occur in this region is important for early identification of Background Information: Femoral head fractures are a com- potentially fatal etiologies . mon injury in the setting of posterior acetabular fractures . While the acetabular fracture is generally well described, the femoral Key Anatomic/Physiologic Issues and Imaging Findings/ head fracture is frequently missed, potentially with devastating Techniques: The exhibit will include normal anatomy of the ili- consequences . The typical imaging features of femoral head frac- opsoas muscle and its appearance on MDCT; mechanisms by tures are reviewed in this presentation, including the Pipkin clas- which disease can spread to the iliopsoas compartment and sification, however the focus of this exhibit is to demonstrate the abnormalities involving the iliopsoas compartment including appropriate management of these injuries, based on the severity infection (including various examples of psoas abscesses second- of the injury as classified by the interpreting radiologist . The ary to organisms such as tuberculosis), hemorrhage, and neo- expected postoperative appearance as well as potential compli- plastic disease . cations will be illustrated . Conclusion: The iliopsoas compartment is an important location Educational Goals/Teaching Points: After completing this edu- of pathology in the body . Spread of pathology to this area can cational activity the participant will be able to recognize that fem- occur via a variety of methods . Understanding the types of oral head fractures are common in the setting of posterior acetab- pathology that can spread to this region, as well as their appear- ular fractures, and the interpreting radiologist must immediately ance on MDCT imaging, is important in early diagnosis . institute a dedicated search for femoral head fractures upon rec- ognition of an acetabular fracture; recognize the types of femoral head fractures; recognize the implications of the femoral head E325. Femoroacetabular Impingement Syndrome: An fracture pattern for patient management; recognize the postoper- Overview (CME Credit Available) ative appearance of femoral head fracture repair, and recognize Bathala, E.; Peterson, J. Mayo Clinic, Jacksonville, FL the potential late complications of femoral head fractures . Address correspondence to E. Bathala (bathala.elizabeth@mayo. edu) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The femoral head is often injured in a patient with Background Information: Femoroacetabular impingement multiple additional distracting injuries . Large portions of the fem- (FAI) is a major factor in the early development of debilitating oral head constitute weight bearing portions of the hip joint, and osteoarthritis of the hip . The syndrome is caused by abnormal unrecognized injury may have devastating functional conse- contact between the osseous protrusions of the acetabulum and quences . Femoral head fractures may be difficult, or impossible, the femur during hip movement . There are two types which can to see by plain film radiography . An appropriate search pattern overlap, the cam type and the pincer type . Each type of FAI is char- must be instituted . The Pipkin classification has important impli- acterized by a different clinical picture as well as different imaging cations for patient management . Followup of the postoperative features . The purpose of this exhibit is to educate radiologists on patient is important to recognize complications or issues requir- the clinical syndrome and the imaging findings of FAI in order to ing further intervention allow earlier detection and treatment . Additionally, there will be specific education concerning the types of treatment for FAI . Conclusion: An appropriate search pattern for femoral head frac- tures, particularly when cued by the presence of acetabular frac- Educational Goals/Teaching Points: The goals are to review tures, allows for a rapid identification and accurate categorization the clinical findings in patients with FAI; distinguish the two types of these injuries . While there remains some controversy as to the of FAI, both anatomically and clinically; review the etiology of management of these injuries, surgical intervention is often indi- each type of FAI; review the imaging findings of FAI on radiogra- cated for injuries to the weight bearing surface of the femoral phy, CT and MRI including specific signs and diagnostic criteria, head . Inadequate management may result in decreased mobility and discuss the various treatment options available to decrease and even joint replacement, and it is further important for the the overall risk of severe early osteoarthritis of the hip necessitat- radiologist to recognize the postoperative appearance and poten- ing joint replacement . tial complications . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Cam type FAI is primarily a femoral abnormality . It is E324. Review of Iliopsoas Anatomy and Patholody as Seen caused by an abnormal femoral head-neck morphology which on MDCT (CME Credit Available) can be identified on lateral hip radiographs by visualizing an off- Gupta, S.; Morgan, J.; Sadler, M. St. Vincent’s Catholic Medical set . MR imaging can be useful by evaluating the anterior alpha Center, New York, NY angle on sagittal oblique imaging which is used to determine the Address correspondence to S. Gupta ([email protected]) sphericity of the femoral head . The Pincer type of FAI is primarily an acetabular abnormality and is caused by acetabular over-cov- Background Information: The exhibit will review anatomy of erage . It can be seen as a “crossover” or “figure-of-eight” sign on the iliopsoas compartment as visualized on MDCT; discuss the radiography . On MR imaging, pincer type FAI can demonstrate a methods by which disease can spread to this compartment; illus- deep acetabulum and signs of osseous impaction along the fem- trate different types of pathology involving the iliopsoas compart- oral neck as well as cartilage damage . 285 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Conclusion: In conclusion, early diagnosis of FAI is important E327. Hardware Failure in Total Hip Arthroplasty: What the because of the debilitating nature of the advanced disease and Orthopedic Surgeon Needs to Know (CME Credit Available) the fact that there are treatment options which can prevent the Roberts, K.; Simoncini, A.; Hollister, A. Louisiana State University progression of the disease . Health Sciences Center-Shreveport, Shreveport, LA Address correspondence to K. Roberts ([email protected])

E326. Femoroacetabular Impingement: Can Indirect MR Background Information: Total hip replacement is the arthro- Arthrography be Considered a Valid Method in Detection of plasty most frequently encountered by the radiologist . According Endoarticular Damages? to the National Hospital Discharge Survey 1998-2005, more than 230,000 total hip replacements were documented in 2005 and Zerbi, A.1; Stradiotti, P.2; Pozzi ,G.3; Sironi, S.3 1. Istituto more than 30,000 total hip replacement revisions were docu- Ortopedico Galeazzi, Milano, Italy; 2. A.O. San Carlo Borromeo, mented in the same year . This number continues to rise with the Milano, Italy; 3. Univerisità Degli Studi Milano-Bicocca, Azienda aging of the American population . Frequent radiographic follow- Ospedaliera San Gerardo, Monza, Italy up is indicated to assess the alignment and stability of these Address correspondence to A. Zerbi ([email protected]) prostheses, and orthopedic surgeons use certain criteria to deter- mine if radiographic findings are of clinical significance in the Objective: Femoroacetabular impingement (FAI) results from an management of total hip arthroplasty . This exhibit will showcase abnormal relationship between the proximal femur and the ace- common imaging findings in several cases of total hip arthro- tabulum . Two distinct types of FAI can be distinguished: “cam plasty failure along with a detailed discussion of which parame- FAI” caused by jamming of an abnormal femoral head and “pin- ters must be assessed for optimal interpretation in order to pro- cer FAI”, that results from acetabular abnormality . That leads to vide the most clinically useful information to referring orthoped- abutment of the femoral neck against the acetabular rim and can ists . When possible, correlation with intraoperative findings will cause labral and/or chondral lesion . Direct MR arthrography be provided . (d-MRa) is actually considered as the gold-standard in detecting intra-articular damages . The aim of this study is to evaluate a Educational Goals/Teaching Points: The goals are to review new method for detecting intra-articular damages correlated to the structure of the basic total hip arthroplasty prostheses fre- FAI, based on an indirect MR arthrography (i-MRa) performed quently encountered by the radiologist; present and describe after endovenous injection of contrast medium and patient’s common imaging findings associated with total hip replacement physical activity . All patients underwent MR, d-MRa and i-MRa; failure, providing correlation with intraoperative findings when results were then compared . possible, and detail the information which should be included in radiologic reports to optimize their utility to the referring clinician . Materials and Methods: Between October, 2007 and July, 2008, 21 hip joints (nine left, 12 right) in 17 patients (eight Key Anatomic/Physiologic Issues and Imaging Findings/ women, nine men; age range, 15–47 years; mean age, 32 years) Techniques: Key imaging findings will be displayed in electronic with clinical suspicion of FAI were examined either at MR imag- format, providing correlation with intraoperative findings when ing, i-MRa and d-MRa . All the patients had previously had an possible . anteroposterior radiograph of the pelvis and a lateral frog-leg radiograph of the affected hip . Sensitivity and accuracy of the two Conclusion: Orthopedic hardware failure in total hip arthroplasty methods have been calculated . Interobserver agreement has is frequently documented by radiographic imaging . Referring been also evaluated with Cohen’s K statistic . orthopedists require detailed information acquired by imaging studies in order to optimize management of the failed prosthesis . Results: Eleven out of 21 hips analyzed had cam-type alterations The radiologist’s report should contain certain clinically relevant (52%), two pincer-type and two mixed cam/pincer-type . The val- information to aid the referring clinician in his or her manage- ues of sensitivity calculated in detection of the labral lesions ment decisions when considering possible revision of total hip were 29% for standard MR and 76% for i-MRa (confidence level: arthroplasty . 95%=0 .2) .The values of sensitivity in detection of late osteoar- thritic changes were 100% for both the methods . The accuracy of standard MR was 67% in detection of condral defects and 38% E328. My Hip Hurts Doc! How Can We Help Referring for labral defects . For the i-MRa the values of accuracy were of Clinicians? 100% in condral defects detection, 76% in labral defects and Smith, S.1; Mazzie, J.2; Scalcione, L.2; Math, K.3; Grossman, M.2; 100% . Both the methods have shown the same accuracy in Katz, D.2 1. University of Maryland, Baltimore, MD; 2. Winthrop- detection late osteoarthritic changes (100%) Direct. MRa did not University Hospital, Mineola, NY; 3. Beth Israel Medical Center, show a significantly higher sensitivity in comparison to indirect New York, NY MRa (p<0 .05) . Address correspondence to D. Katz ([email protected])

Conclusion: MR arthrography is an indispensable instrument for Background Information: The history accompanying radio- the detection of condral and labral lesions and it gives important graphs of the pelvis and hip from the emergency department will data in patient surgical planning . Indirect MRa has a significantly often state simply “hip pain” . What does that mean for the radiol- higher sensitivity compared to traditional MR and sensitivity ogist, and what should be assessed on every hip and pelvic radi- equal to that of direct MRa . Indirect MRa is also easily reproduci- ograph? The purpose of this exhibit is to present the imaging ble and might be the imaging modality of choice in detecting findings of common and uncommon causes of hip pain using a condral lesions in FAI . variety of imaging modalities .

286 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Educational Goals/Teaching Points: Fractures, both traumatic E331. Cervical Spine Trauma: Correlation Between MDCT and pathologic, inflammatory processes, and femoral acetabular and MRI (CME Credit Available) impingement syndrome, will be presented and reviewed . Cortes, C.; Garcia, L.; Ballester, G.; Gomez, A.; Colon, E.; Vidal, J.; Additionally, findings such as bursitis, labral tears, and Rivera, G. University of Puerto Rico, San Juan, PR osteonecrosis will be reviewed . Other nonprimary hip patholo- Address correspondence to C. Cortes ([email protected]) gies will be shown, including sacral insufficiency fractures, disc herniations which can cause referred pain, and unanticipated Background Information: About 12,000 to 13,000 cervical abdominal pathology such as hernias, renal and ureteral calculi, spine injuries occur yearly in the United States, of which an esti- and vascular lesions . Herniation pits, which are associated with mated 6,000 result in death and 5,000 in quadriplegia . femoral acetabular impingement syndrome, will also be dis- Approximately 80% of these patients are between the ages of 18 cussed . to 25 years . The premature death or disability of these individuals has a large economical and social impact . The radiologist plays Key Anatomic/Physiologic Issues and Imaging Findings/ an important role in identifying these injuries and providing infor- Techniques: The emphasis will be on plain radiographic findings mation that will influence clinical management . Given the and the differential diagnosis, but cross-sectional imaging find- increased role of MDCT and MRI in the evaluation of the trauma ings of hip pathology in patients presenting with pain will also be patient, it is imperative for the radiologist to be familiar with the presented, including CT and MR examinations . normal cervical spine anatomy, as well as to be able to identify the most common cervical spine injuries using these modalities . Conclusion: The radiologist needs to keep in mind the spectrum of pathology, musculoskeletal or otherwise, which may cause Educational Goals/Teaching Points: After completing this edu- patients to present with hip/pelvic pain and to undergo plain cational activity the participant will be able to describe the nor- radiographic studies, particularly in the emergency department mal cervical spine anatomy (MDCT and MRI); review the most setting . common patterns of cervical spine injuries; understand the importance of using multiplanar reconstructions (MPR); under- stand the complementary role of cervical MRI to MDCT, particu- E330. Sacral Pathology Revisited: A Multimodality Approach larly for evaluation of soft tissues, ligaments and the spinal cord, Cao, M.1; Masih, S.1,2; Modarresi, S.1,2 1. University of California, and correlate post-traumatic findings in MDCT and MRI . Los Angeles, Los Angeles, CA; 2. Veterans Administration West Los Angeles Medical Center, Los Angeles, CA Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to M. Cao ([email protected]) Techniques: We will review the normal osseous and ligamen- tous anatomy of the cervicocranium and lower cervical spine as Background Information: The purpose of this exhibit is to seen on MDCT and MRI modalities . We will show selected cases review the ligamentous, nervous and bony anatomy of the sac- from our trauma level 1 center facility including cervicocranial rum; discuss key radiographic findings in a spectrum of patholog- injuries, such as dislocations, subluxations, and fractures . Injuries ic conditions involving the sacrum, and highlight the use of multi- of the lower cervical spine, including hyperflexion, axial compres- ple imaging modalities in the diagnosis of sacral conditions . sion, and hyperextension injuries will also be included .

Educational Goals/Teaching Points: The exhibit will include a Conclusion: Post-traumatic cervical spine injuries are very com- review of sacral anatomy (including bones, ligaments, joints, and mon and are a major cause of disability . MDCT plays a primary nerves) ; congenital lesions of the sacrum ; infection of the sac- role in the evaluation of patients with cervical spine trauma . rum; trauma in the sacrum, and neoplastic tumors of the sac- Cervical MRI is a useful complement to MDCT, particularly for rum (including sacral canal tumors, benign bony lesions, malig- evaluation of ligamentous and spinal cord injuries . Therefore, a nant bony neoplasms) . thorough knowledge of the normal cervical spine anatomy, as well as familiarity with the findings of the most common patterns Key Anatomic/Physiologic Issues and Imaging Findings/ of post traumatic injury to the cervical spine are needed to ade- Techniques: A multimodality approach including plain radiogra- quately contribute to patient care . phy, CT, and MRI is taken in the study of the bony and soft-tissue components of the sacrum . Key radiographic findings will be highlighted for various pathologies . E333. Using Reformatting Algorithms for Optimum Thoracolumbar Spine Imaging Conclusion: After the review of this exhibit, the participant Merchant, N.; Jaffer, N.; Ghai, S. University of Toronto, Toronto, should be able to describe the anatomy of the sacrum, discuss Canada the imaging findings of a variety of congenital, infectious, trau- Address correspondence to N. Merchant (neesha.merchant@ matic and neoplastic sacral conditions, and recognize the value gmail.com) of x-ray, CT and MRI in the diagnosis of sacral pathologies . Background Information: With the introduction of multislice CT scans, isotropic or near-isotropic reformatting of axial images from raw data has enhanced the interpretation of abdominal imaging studies . The use of sagittal reconstruction has been rou- tinely used in chest imaging; however, with the exception of CT angiographic assessment of the splanchnic circulation, sagittal reconstruction is not commonly utilized for abdominal imaging studies . The bony structures of abdomen are difficult to evaluate on CT studies with axial and coronal imaging alone . 287 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Educational Goals/Teaching Points: This exhibit will demon- E335. CT Fluoroscopy-Guided Percutaneous Sacroplasty for strate the value of sagittal reformatting of abdominal imaging the Treatment of Sacral Insufficiency Fractures: Results of studies to evaluate osseous abnormalities that are often over- 19 Patients looked with the current axial and coronal image formats . Kim, H.; Lee, S. Seoul Wooridul Hospital, Seoul, South Korea Address correspondence to H. Kim ([email protected]) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Many osseous pathologies, such as disc disease, Objective: The objective is to describe the efficacy and safety of focal metastasis, spinal trauma, lumbar canal stenosis, spondylol- percutaneous sacroplasty under CT-fluoroscopy guidance, and to isthesis, and subtle findings of early ankylosing spondylitis are illustrate the technique and results of the method based on a best evaluated on sagittal views . series of 19 patients .

Conclusion: In adjunct to axial and coronal views, examination Materials and Methods: From June, 2006 to June, 2008, we of the sagittal view allows for a thorough evaluation of abdomin- performed CT-fluoroscopy guided percutaneous sacroplasty in 19 al imaging studies, especially for the detection of osseous abnor- female patients who had sacral fracture and suffered from severe malities . Reformatting programs are built into all multislice CT back and buttock pain . Their mean age was 76 1. years (range, scanners and accordingly, it is recommended that sagittal 66-83 years), mean body mass index (BMI) was 147 .2 (range, reformatting be routinely used as part of a complete abdominal 137-160), and mean bone mineral density (BMD) was -4 1. imaging study . (range, -0 .4 to -6 .7) in L-spine and -4 3. (range, -3 2. to -5 .9) in femur . All procedures were performed under local anesthesia using aseptic technique with the patient positioned prone on the E334. ABCS: A Systematic Approach to the Radiographic CT table . Vital signs were monitored by the radiology nursing Interpretation of the Thoracolumbar Spine with Illustration staff . We injected PMMA using an 11gauge or 13 gauge trocar of Its Usefulness needle(s) with beveled tip under CT-fluoroscopy guidance . After Kim, Y.; Mansfield, L. Brooke Army Medical Center, San Antonio, TX the procedures, a CT scan of the sacrum and pelvis was per- Address correspondence to L. Mansfield (liem_mansfield@hot- formed to confirm whether or not there was a leak of the PMMA mail.com) solution especially into the neural foramens, vascular lumens and retroperitoneal spaces . All patients were assessed for relief of Background Information: Low back pain is a common clinical pain with VAS score (0 to 10), before and one day after the pro- complaint . Radiography remains the primary initial imaging eval- cedure, and were followed for 4-27 months . uation of back pain . Results: Technical success with adequate distribution of PMMA Educational Goals/Teaching Points: The purposes of this cement into the marrow spaces of the sacrum on imaging was exhibit are to review the pertinent anatomy of the spine; intro- achieved in 18 patients (95%) of the 19 patients . One patient duce a systematic approach to the radiographic interpretation of had mild numbness and tingling sensation of her lower leg dur- the thoracolumbar spine; illustrate the effectiveness of this ing the procedure because of a small cement leak into the ipsi- approach, and present a summary of the most common disor- lateral L5-S1 neural foramen through the fracture crack . We ders affecting the thoracolumbar spine . immediately performed an epidural steroid injection into the neural foramen under CT-guidance, and the patient’s symptom Key Anatomic/Physiologic Issues and Imaging Findings/ was relieved . Two to five trocar needles were placed (mean, 2 .9) Techniques: Denis traditionally described three columns of the and 2 .5 cc to 11 5. cc (mean, 5 .71 cc) of PMMA was injected for spine: anterior, middle and posterior . Recently, Berg described a the treatment . Before the treatment, 15 patients could not walk possible fourth column of the thoracic spine, the sternal-rib com- by themselves, and others had difficulty in walking to the bath- plex . A systematic approach to the radiographic interpretation of room . Initial mean VAS score improvement was six (range, 2-7), the thoracolumbar spine is summarized by the abbreviation and following was 6 .4 (range, 4-7) . One day after the procedure, ABCS: Alignment—Disorders with abnormal alignment include all patients could walk to the bathroom by themselves . One burst fracture, Chance fracture, thoracic and costovertebral frac- patient had the procedure twice because of refracture three ture dislocations, scoliosis, and spondylolisthesis due to either weeks after the first procedure with temporary relief of her spondylolysis or facet arthropathy . Bone—The vertebral bodies symptoms . are evaluated for density and shapes, such as bullet, corduroy, “H”, hooked, humped, ivory, picture frame, plana, rugger-jersey, Conclusion: Under CT-fluoroscopy guidance, sacroplasty is an sandwich, scalloping, and squaring which can be pathognomonic effective and safe method in the treatment of sacral insufficiency for certain diseases . Cartilage—The intervertebral disc spaces and fractures that can provide substantial pain relief within a short facet joints are evaluated for discitis and calcification . “S” is for time . soft tissue, sacroiliac joints, and sacral foraminal lines which may be abnormal due to neoplasm, sacroiliitis, or fracture .

Conclusion: Radiography remains the initial imaging evaluation of the spine, which has complex anatomy . This educational exhibit reviews the pertinent anatomy of the spine, introduces a systematic approach to interpreting radiographs of the thoraco- lumbar spine (the ABCS method), and illustrates the pathogno- monic radiographic appearance of the most common disorders affecting the spine .

288 El e c t r o n i c Ex h i b i t s : Musculoskeletal

E336. Pictorial Review of Current Lumbar Interbody Fusion the various disorders manifested as nerve root enhancement . Techniques–Radiographic and Clinical Correlation (CME These can be the degenerative, inflammatory, infectious, and Credit Available) malignant conditions . The radiologic features and its differential Chen, L.; Regev, G.; Gentili, A. University of California-San Diego diagnosis of each disease will be illustrated . Medical Center, San Diego, CA Address correspondence to L. Chen ([email protected]) Conclusion: Normal structures of spine can mimic nerve roots enhancement . There are various disorders manifested as nerve Background Information: The goal of this educational exhibit is roots enhancement . Recognition of these diseases entities would to present state-of-the-art lumbar interbody fusion techniques help direct patient management . including indications, surgical techniques and radiographic appearance . E338. Granulocytic Sarcoma of the Spine: MR Imaging and Educational Goals/Teaching Points: Imaging is an important Clinical Review complement to clinical evaluation which can provide accurate Park, J.1; Seok, J.2; Kim, S.2; Choi, J.3 1. St. Mary’s Hospital, morphologic information of the spine to guide therapeutic deci- Seoul, South Korea; 2. The Catholic University of Korea, Seoul, sions and provide postsurgical evaluations . South Korea; 3. St. Paul’s Hospital, Seoul, South Korea Address correspondence to J. Park ([email protected]) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The most common surgical indication for spinal Background Information: Granulocytic sarcoma (chloroma) is a fusion is segmental instability . Common causes for instability tumor formed by myeloid precursors in an extramedullary site include degenerative disc disease, facet arthropathy, iatrogenic and is associated with myeloid leukemias and other myeloprolif- causes such as previous excessive surgical decompression with erative disorders . We present the MR imaging findings and clini- removal of more than 50% of the facet joints, and post-traumatic cal manifestations of 33 cases of spinal chloroma . and congenital etiology . Current widely used surgical techniques include anterior (ALIF), posterior (PLIF), and transforaminal lum- Educational Goals/Teaching Points: The average age of the bar interbody fusion (TLIF) . Minimally invasive extreme lateral patients (22 males and 11 females) was 32 years . There were 24 interbody fusion (XLIF) is an increasingly promising new tech- acute myelogenous leukemias, four acute lymphocytic leukemias nique . Additionally, new technologies include polyetheretherke- and five chronic myelogenous leukemias . Nine patients manifest- tone (PEEK) composite radiolucent cages, recombinant human ed with granulocytic sarcoma as a presenting sign and the bone morphogenetic protein-2 (rh-BMP-2), and artificial disc remaining 24 were diagnosed during remission phase or relapse replacement . period . All patients received radiotherapy with combined chemo- therapy and three patients underwent surgical decompression . Conclusion: By the end of this educational exhibit, the reader MR imaging of spine was performed in all patients with follow will be able to identify the most common indications for spinal up MR imaging in 24 patients . fusion, better understand the various current surgical techniques, and provide more accurate interpretation of preoperative and Key Anatomic/Physiologic Issues and Imaging Findings/ postoperative imaging for lumbar spinal fusion . Techniques: All patients complained of lower back pain, with other complaints including radioculathies, numbness and pain in the extremities, and paraplegia . The lumbosacral (15 cases) and E337. Nerve Root Enhancement on Contrast-Enhanced MR: thoracic (13 cases) spines were commonly involved, and three of Differential Considerations the 33 patients exhibited multiple noncontiguous areas of Choo, H.; Lee, S.; Kim, M. Inje University Pusan Paik Hospital, involvement . MR imaging demonstrated multiple epidural masses Busan, Korea and obliteration of the spinal canal with parameningeal exten- Address correspondence to H. Choo ([email protected]) sion mainly through the neural foramina, resulting in thickening of multiple nerve roots . Lesions were isointense to bone marrow Background Information: Single or multiple extramedullary on both T1- and T2-weighted MR images with homogeneous enhancing lesions along cauda equina of the lumbosacral intra- enhancement after injection of contrast medium . dural space on contrast-enhanced MRI are often encountered . It can be the normal anatomy of spine or the true abnormality . This Conclusion: Increased awareness of imaging findings of granulo- exhibit describes the normal anatomy to mimic the enhancement cytic sarcoma will facilitate early diagnosis and minimize poten- of true nerve roots and the various diseases manifested as nerve tially preventable neurological morbidity . roots enhancement .

Educational Goals/Teaching Points: The goals are to illustrate E339. Resolving Spontaneous Spinal Epidural Hematoma: normal anatomy to mimic the enhancement of the nerve root, Evolution of MR Signal Characteristics and describe the various disorders manifested as nerve root Theodorou, D.1; Theodorou, S.1; Kakitsubata, Y.2; Tsampoulas, enhancement . C.3 1. University of California, San Diego; San Diego, CA; 2. Miyazaki Shakaihoken Hospital, Miyazaki, Japan; 3. University of Key Anatomic/Physiologic Issues and Imaging Findings/ Ioannina, Greece, Ioannina, Greece Techniques: The normal anatomy of great radicular vein or filum Address correspondence to S. Theodorou ([email protected]) terminale can mimic nerve root enhancement . However the ten- dency of typical location of normal anatomy is helpful for the dif- Objective: Spontaneous spinal epidural hematoma (SSEH) is a ferential diagnosis from true nerve root enhancement . There are rare condition that can result in rapidly progressive and severe

289 El e c t r o n i c Ex h i b i t s : Musculoskeletal neurological deficits requiring urgent intervention . Although treat- Furthermore, we attempt to give an insight into the mechanism ment of SSEH mandates early decompression of the spinal canal, of nerve root compression seen in vacuum disk phenomenon . in case of progressive neurologic improvement, nonsurgical man- agement may be warranted . We describe the MR signal charac- Materials and Methods: The medical records, cross-sectional teristics of resolving SSEH that ensure accurate diagnosis and imaging studies (CT, MR imaging, CT and CT discog- monitoring of the former condition . raphy), and available surgical findings in four symptomatic patients (two men, two women; ages 51-72 years) with epidural Materials and Methods: Three patients with acute onset of spi- and intradiskal gas collections were reviewed . Three patients nal pain, with (n=2) or without (n=1) associated radiculopathy underwent surgery and one patient was treated conservatively . developed motor dysfunction (n=1) or sensory disturbances (n=1) in the lower limbs . There was no history of antecedent blunt trau- Results: In all cases, clinical symptoms of epidural gas collection ma, bleeding disorder or anticoagulant therapy . All patients under- were identical to those of other more common causes of nerve went initial and repeat MR imaging studies until complete neuro- root compression . CT and MR imaging studies disclosed intraspi- logic recovery and resolution of SSEH on MR images . nal and intradiskal gas accumulation . On CT images, gas bubbles appeared hypodense, while on MR images gas was of low signal Results: MR imaging studies demonstrated a cervical (n=1) or intensity on both the T1- and T2- weighted images . Epidural gas thoracolumbar (n=2) mass located in the dorsal (n=2) or dorso- cysts were present at the L4 or L4-L5 level in two patients and at lateral (n=1) aspect of the epidural space . The craniocaudal the L5-S1 level in the other two patients . In two cases, there was extent of the SSEH varied from two to three vertebral levels . All filling of the epidural gas cyst with contrast material on CT dis- three SSEHs closely conformed to contours of bone . There were kography indicating free communication between intradiskal and no concomitant disk herniations or annular tears . The MR imag- epidural gas . Needle aspiration of epidural gas resulted in com- ing signal characteristics of the epidural mass were variable and plete relief of radicular symptoms in three patients . The gas dis- appeared to depend on the time interval between imaging and appeared spontaneously in the other patient . One year later, all the age of hematoma . On T1-weighted images the mass patients were completely free of symptoms . appeared isointense to the spinal cord, with increasing signal intensity over time . On T2-weighted images, the mass was heter- Conclusion: Although the vacuum disk is considered to be a ogeneously hyperintense to spinal cord with focal regions of low common finding of no or little pathologic significance, our results signal intensity . There was compression of the adjacent spinal show that intradiskal gas may occasionally leak into the spinal cord with no signal changes within it . canal and cause clinical symptoms . Epidural gas collections can be a cause of lumbar radiculopathy and should be considered in Conclusion: The clinical findings in SSEH are similar to those in the differential diagnosis of low back pain . MR imaging comple- acute disk herniation, with acute onset of pain and rapid progres- mented with CT permits confident diagnosis of the condition that sion of symptoms . The MR imaging appearance of SSEH is that of may eliminate remnant neurologic abnormalities . a relatively large dorsal or dorsolateral mass that is usually situat- ed in the thoracolumbar region, compressing the adjacent thecal sac and traversing nerve roots . Increasing MR signal intensity E341. MR Findings of Pyogenic Facet Joint Infection within the epidural mass with time on T1-weighted images is Fujisawa, H.; Kushihashi, T.; Baba, M.; Ukisu, R.; Takenaka, H.; suggestive of the diagnosis . MR imaging may provide additional Fukushita, T.; Yagi, S. Showa University Northern Yokohama information regarding the extent of SSEH and the degree of spi- Hospital, Kanagawa-Ken, Japan nal canal compromise . Also, MR imaging proves well-suited in Address correspondence to H. Fujisawa ([email protected]) the determination of the age of the hematoma, and for monitor- ing conservative treatment of SSEH . Objective: Pyogenic arthritis of spinal facet joints is a rare condi- tion . The purpose of this study is to analyze the clinical presenta- tion, diagnostic laboratory tests, and radiological characteristics E340. Symptomatic Epidural Gas Cyst Associated With especially on MR images, of pyogenic lumbar facet joint infec- Vacuum Disk: Evaluation With CT and MR Imaging tions (PLFJI) . Theodorou, D.1; Theodorou, S.1; Kakitsubata, Y.2; Tsampoulas, C.3 1. University of California, San Diego, San Diego, CA; 2. Materials and Methods: This was a retrospective review of 11 Miyazaki Shakaihoken Hospital, Miyazaki, Japan; 3. University of cases of PLFJI at our institution from April, 2004 through July, Ioannina, Greece, Ioannina, Greece 2008 . There were seven men and eight women, with age range Address correspondence to S. Theodorou (rjtheodorou@hotmail. 49-85 years (mean 69 3. years) . All 15 patients had laboratory com) tests, plain lumbar spine radiographs (frontal and lateral view), and MRI . Gd-contrast enhancement MR was performed in 13 Objective: The vacuum disk phenomenon refers to gaseous col- patients . We analyzed clinical features, laboratory findings, plain lections in intervertebral disk spaces . Although vacuum phenome- radiograph findings, and MR images . On MR images, we evaluat- non has generally been equated with the presence of degenera- ed the findings of infected facet joint, a presence of paraspinal tive disk disease, gaseous collections may accompany other disor- extension, paraspinal abscess, epidural abscess, psoas abscess, ders of the disk and adjacent vertebrae . Less commonly, gas can and spondylodiscitis . be localized to the spinal canal . Intraspinal gas can be asympto- matic; however, it is a well recognized, albeit rare cause of lumbar Results: All 15 patients complained of lumbar pain . Fever was radiculopathy . We report the CT and MR imaging findings in present in 14 patients . White blood cell counts and C-reactive patients with lumbar nerve root compression associated with a protein were elevated in all cases . We could not diagnose PLFJI vacuum disk, which was communicating with the epidural space . on plain radiographs in all cases . MR findings in PLFJI were high

290 El e c t r o n i c Ex h i b i t s : Musculoskeletal signal intensity on T2WI and enhancement on fat-saturation E343. Evaluation of Rotator Cuff Tear Arthropathy by MRI Gd-T1WI at infected facet joint in all cases, unilateral was nine and Radiography and bilateral was six, paraspinal extension was 15, paraspinal Ashikyan, O.; Motamedi, K.; Seeger, L.; Motamedi, A. University abscess was six, epidural abscess was three . Psoas abscess and of California Los Angeles, Los Angeles, CA spondylodiscitis were none . Address correspondence to O. Ashikyan ([email protected])

Conclusion: The clinical features and laboratory data in PLFJI Objective: The objective is to characterize and compare MRI and were not specific . The PLFJI may spread to paraspinal and epidur- radiographic findings in patients with rotator cuff tear arthropa- al spaces easily . MRI is the most suitable diagnostic modality to thy . detect not only facet joint changes but also complications in par- aspinal and epidural extension and abscess formation . Materials and Methods: We have reviewed 30 MRIs and radio- graphs in 28 patients with full-thickness rotator cuff tears, which measured more than 3 cm . The acromiohumeral distance, gle- E342. Illustrative Review of Superior Labral Anterior- noid concavity, and glenohumeral distance were measured on Posterior Lesions of the Shoulder: Patterns and Pitfalls MRIs and radiographs . We also evaluated rotator cuff tendons (CME Credit Available) and muscles, biceps tendon, labrum, and osseous structures . Motamedi, D.1; Modarresi, S.2; Masih, S.2 1. Cedars-Sinai Medical Center, Los Angeles, CA; 2. University of California, Los Results: The radiographs were normal in nine patients and Angeles/Veterans Administration of Greater Los Angeles, Los demonstrated Stage Ia cuff tear arthropathy in 13 patients . Stage Angeles, CA IIa arthropathy was present in five patients and stage IIb in one . Address correspondence to D. Motamedi ([email protected]) Mean cuff tear measurements were 3 .5 cm in anteroposterior dimension and 3 5. cm in mediolateral dimension . The suprasp- Background Information: Shoulder pain in young athletes can inatus was torn on all studies (100%) . An infraspinatus tear was be nonspecific and originate from various causes . Superior labral present in 87% of studies . A subscapularis tear was seen in anterior-posterior (SLAP) lesions are prevalent cause of such 30% of studies . A teres minor tear was present on one study pain . The purpose of this presentation is to review anatomy of (3%) . Biceps tendon pathology was present in 80% of studies . the glenoid labrum and related structures, to describe the mech- The mean acromiohumeral distance was 3 mm on MRI, and 5 .9 anism of injury, to show different types and severity of labral mm on radiographs . Rounding of greater tuberosity was present tears and to show MRI approach to these lesions . The ability to in 33% of studies and greater tuberosity marrow edema and accurately diagnose these conditions is necessary for the radiolo- subcortical cysts were present in 63% and 70% of scans, respec- gist to recommend appropriate study such as MR and tively . Two findings of an “acetabularized” appearance of acromi- lead the referring physician to reaching the correct diagnosis and al undersurface included undersurface remodeling and undersur- appropriate treatment . face spurs . Acromial marrow edema was present in 70% of cases . The mean glenohumeral distance was 3 .1 mm on MRI Educational Goals/Teaching Points: This exhibit will provide an and 4 .5 mm on radiographs . The mean glenoid concavity was overview of various causes of nonspecific shoulder pain in young measured 4 .2 mm on MRI and 7 .2 mm on radiographs . Glenoid athletes, and a pictorial review of different types of SLAP tears osteophytes were present in 50% of cases . Glenoid marrow and show extension of these tears to different areas of the edema was seen in 20% of cases and subchondral cysts were labrum, to middle glenohumeral ligament and to rotator interval . seen in 10% of cases . Maceration of the glenoid labrum was evi- It will also review the mechanism of injuries leading to superior dent in 53% of cases . Humeral head osteophytes were demon- labral anterior-posterior tear; review the related anatomical struc- strated in 60% of cases . Humeral head marrow edema and sub- tures such as glenohumeral ligaments, rotator interval and the articular cysts were present in 23% and 13% of cases, respec- bicipitolabral complex, and describe the appropriate imaging tively . technique, positioning and pulse sequences for detection of superior labral tears . Conclusion: In addition to radiography, MRI is a valuable tool in evaluation of arthropathy in patients with large cuff Key Anatomic/Physiologic Issues and Imaging Findings/ tears . “Acetabularization” of acromion may be present due to Techniques: This will be a didactic presentation of SLAP lesions hypertrophic changes or due to undersurface erosions . The resulting in chronic pain in active individuals and young athletes glenohumeral and acromiohumeral distances, and glenoid con- organized by anatomy, mechanism of injury and imaging character- cavity were smaller when measured on MRI compared to radio- istics . The role of MRI, indications for MR arthrogram, anatomical graphs . Acromial marrow edema and osteophytes, edema and variations and pitfalls of the superior labral tears will be discussed . subcortical cysts in greater tuberosity, glenohumeral osteophytes, The value of clinical correlation, appropriate positioning and MR maceration of glenoid labrum and biceps tendon pathology were sequences for reaching the correct diagnosis are emphasized . the most common findings in our study .

Conclusion: After reviewing this educational exhibit, radiologists will recognize the MR appearance and distinguish different types of SLAP tears with or without extension to adjacent structures; recognize the value of a systematic approach to MR diagnosis of SLAP lesions, imaging technique, and clinical and arthroscopic correlation; recognize the importance of recommending MR arthrogram in nonconclusive MRI cases in the appropriate age group and clinical setting, and understand treatment options available for different types of superior labral tears . 291 El e c t r o n i c Ex h i b i t s : Musculoskeletal

E344. Lesser Tuberosity Cysts: Incidence and Associated E345. The Rotator Interval: MR Arthrographic Anatomy and Rotator Cuff Pathology Signs of Injury Wissman, R.1; Kapur, S.1; Akers, J.1; Crimmons, J.2; Ying, J.1; Huang ,W.1; Masih, S.1,2; White, E.3 1. University of California, Meganathan, K.1; Laor, T.3 1. University of Cincinnati , Cincinnati, Los Angeles, Los Angeles, CA; 2. VA West Los Angeles, Los OH; 2. Radiology Associates of Northern Kentucky, Crestview Hills, Angeles, CA; 3. University of Southern California, Los Angeles, CA KY; 3. Cincinnati Children’s Hospital Medical Center, Cincinnati, OH Address correspondence to W. Huang ([email protected]) Address correspondence to R. Wissman (wissmaRD@healthall. com) Background Information: The rotator interval (RI) is an incom- pletely characterized region of the anterior shoulder joint between Objective: Humeral head cysts have a known association with the supraspinatus and subscapularis tendons which is increasingly rotator cuff disease . Cysts of the greater tuberosity have been recognized as an important contributor to glenohumeral stability . well studied, however relatively little is known of the clinical sig- Injuries to the rotator interval are becoming an increasingly recog- nificance of lesser tuberosity cysts . The purpose of our study is to nized source of inferoposterior shoulder instability . determine the incidence of cysts of or near the lesser tuberosity and their association with rotator cuff pathology and impinge- Educational Goals/Teaching Points: This exhibit will review MR ment . arthrographic anatomy of RI structures; diagram mechanisms of RI injury, and illustrate radiologic signs of RI injury . Materials and Methods: A retrospective review of 1,000 con- secutive MRI exams of the shoulder was performed by consensus Key Anatomic/Physiologic Issues and Imaging Findings/ by two radiologists . Lesser tuberosity cysts were grouped by their Techniques: Important structures in the rotator interval include location into type 1 (superior to the lesser tuberosity) and type the coracohumeral ligament, superior glenohumeral ligament, 2 (at the insertion site of the subscapularis on the lesser tuberos- joint capsule, and biceps brachii tendon . A review of rotator inter- ity) . If cysts were found at both locations they were included in val anatomy using images from shoulder MR arthrography is pre- the type 2 group . The rotator cuff was defined as intact, partial or sented, with anatomic correlation with nonarthrographic shoul- completely torn . Severe tears of the supraspinatus included high der MR images . Radiological signs including an obliterated subc- grade and complete tears . Severe tears of the subscapularis oracoid fat pad and landmarks important for recognition of rota- included moderate and high grade tears . Partial tears were fur- tor interval injuries will be demonstrated using images from ther subdivided into mild, moderate and high grade tears . The patients demonstrating evidence of shoulder instability and dam- shortest distance from the coracoid to the humeral head was age to rotator interval structures on MR arthrography . measured on axial images . These findings were compared to an age and gender matched control without evidence of lesser Conclusion: Injury to the rotator interval may be a cause of tuberosity cysts on MRI exams of the shoulder . shoulder instability . Evaluation of the rotator interval is performed with MR arthrography . Important structures to evaluate in the Results: A total of 48 patients (age range 35-79 years, mean 61 rotator interval are the coracohumeral ligament, superior gleno- years) were found with lesser tuberosity cysts . Thirty-two had humeral ligament, joint capsule, and biceps brachii tendon . type 1 cysts and 16 (33%) type 2 cysts . There was no significant difference in severe subscapularis or severe supraspinatus tears in type 1 cysts when compared to controls . Type 2 cysts were E346. Current Imaging Options for Shoulder Injuries Related found to be significantly associated with severe subscapularis to Golf tears (69%) as compared to controls (38%, p=0 .035) and type 1 Pinchcofsky, H.; Young, P. Case Western Reserve University, cysts (22%, p=0 .003) . Type 2 cysts were also significantly associ- Cleveland, OH ated with severe supraspinatus tears (81%) as compared to con- Address correspondence to H. Pinchcofsky ([email protected]) trols (44%, p=0 .007) and type 1 cysts (31%, p=0 .001) . Coracohumeral distance of less than 10 mm was noted in 63% Background Information: Multiple injuries of the shoulder have of type 2 cysts as compared to controls (33%, p=0 .045) and type been found to be attributable to golf . In some cases, the injury 1 cysts (31%, p=0 .043) respectively . pattern varies between professional golfers and amateurs . In order to familiarize practicing radiologists with injuries of the Conclusion: Cysts of or near the lesser tuberosity cysts are not shoulder specific to golf, we review the literature which discusses uncommonly seen in shoulder MRI exams . Cysts just superior to such injuries . We also discuss imaging findings and techniques the lesser tuberosity (type 1) are more common than cysts at the insertion site of the subscapularis tendon (type 2) and are not Educational Goals/Teaching Points: The golf swing involves associated with cuff pathology . Type 2 cysts are associated with cross-body adduction in the backswing and follow-through por- severe subscapularis and supraspinatus tendon pathology as well tions . This predisposes golfers to subacromial impingement, as a decreased subcoracoid distance . acromioclavicular and glenohumeral joint osteoarthritis, and glenohumeral instability . The nondominant, leading shoulder in the golf swing is usually the affected shoulder . Rotator cuff tendi- nosis and tearing are also common injuries in golf . Age is an important factor in predicting the etiology of diseases in the shoulder joint . In older individuals, subacromial impingement and rotator cuff disease is caused by acromioclavicular osteo- phytes . For younger golfers, subacromial impingement is caused by hyperlaxity of the glenohumeral joint, weak or imbalanced rotator cuff muscles, or a tight posterior capsule .

292 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Key Anatomic/Physiologic Issues and Imaging Findings/ E348. The MR Arthrographic Anatomy of the Biceps Labral Techniques: Rotator cuff tears may be evaluated with either MRI Insertion and its Morphological Significance With Labral or ultrasound . Rotator cuff tears are characterized by areas of Tears in Patients With Shoulder Instability hyperintensity on T2-weighted images in the area of abnormality Jakanani, G.; Rennie, W. Leicester Royal Infirmary, Leicester, on MRI . Retraction of the musculotendinous junction may also United Kingdom be seen with full thickness rotator cuff tears . MRI remains the Address correspondence to G. Jakanani ([email protected]) most comprehensive method of assessing rotator cuff and shoul- der pathology . On ultrasound, areas of pathology correspond to Objective: The attachment of the long head of biceps tendon is anechoic areas . Tendinosis is characterized by thickened tendons described in traditional anatomy texts as being at the supragle- with intermediate signal on MRI . This same entity appears hypoe- noid tubercle of the scapula . There are however differing views choic and heterogenous on ultrasound . Although unenhanced with reports in the literature of cadaveric work that has shown MR sequences, particularly T2-weighted images, are the conven- that most of the tendon fibers attach just posterior to the tuber- tion for diagnosing rotator cuff pathology, some authors now cle and the labrum . We aim to define the anatomic biceps labral advocate using MR arthrography for this purpose because of an attachment as demonstrated by MR arthrography of the shoulder, increased diagnostic yield . MR arthrography using T1-weighted and to determine the relationship between the attachment site sequences with fat suppression can also be very helpful in and type of labral tears seen in patients with recurrent shoulder assessing shoulder pathology . Glenohumeral instability and labral dislocation . pathology are best evaluated with such imaging methods . Materials and Methods: This was a retrospective study of MR Conclusion: The shoulder is susceptible to injuries from the golf shoulder arthrograms performed during a two-year period by a swing . Although ultrasound can be helpful in diagnosing shoul- fellowship trained musculoskeletal radiologist at a university der pathology, MRI remains the most comprehensive and com- teaching hospital . Forty-eight patients (33 males and 15 females, monly used modality to evaluate the shoulder . MR arthrography age range 17-72 years, mean 32 years) were included in this can aid in a higher diagnostic yield for shoulder pathology when study . Postcontrast sagittal oblique proton density fat saturated used appropriately . images were reviewed on a PACS workstation by two readers to determine the attachment of the biceps tendon in relation to the 12 o’ clock position of the glenoid fossa . E347. The Injured Patient’s Shoulder: Clinical Correlation and MR Findings (CME Credit Available) Results: Twenty-two patients (46%) had a completely posterior Mazzie, J.1; Chang, W.2; Smith, S.2; Luchs, J.1; Lazzara, B.1; Katz, attachment . In 11 patients (23%) the tendon attachment was D.1; Grossman, M.1 1. Winthrop-University Hospital, Mineola, NY; predominantly posterior but with some fibers attaching to the 2. University of Maryland, Baltimore, MD tubercle . Fifteen patients (31%) had the traditional 12 o’clock Address correspondence to D. Katz ([email protected]) configuration . Further results on associated labral tears are under analysis and will be presented . Background Information: The shoulder is one of the most common MR examinations encountered in a busy musculoskele- Conclusion: This study presents radiological evidence to support tal imaging practice . The interpreting radiologist should be aware previous cadaveric work that has shown that the attachment of of the variety of physical examination tests which patients may the tendon of the long head of biceps is not directly onto the have undergone by our clinical colleagues prior to seeing the glenoid tubercle, but most commonly posterior . The type of doors of a radiology department/practice . attachment may have important implications on the injury pat- tern seen in glenoid labral tears in patients with recurrent shoul- Educational Goals/Teaching Points: This exhibit will be an der dislocation . interactive PowerPoint presentation that will demonstrate a visual correlation between the specific orthopedic physical examination tests or maneuvers of the shoulder and the MR findings of the E349. Ultrasound-Guided Glenohumeral Injection Using the shoulder, with that specific injury . Clinical tests to be discussed Rotator Cuff Interval for MR Arthrography will be organized according to the anatomic region for which it is Andrews, T.1,2; Ali, K.1,3; Knudtson, J.1; Joshi, A.1 1. University of used for, in evaluating the shoulder (i .e ., labrum, rotator cuff, Kansas School of Medicine, Wichita, KS; 2. Wesley Medical acromioclavicular disease, etc .) . Center, Wichita, KS; 3. Cypress Imaging, Wichita, KS Address correspondence to T. Andrews (tylerandrews2003@ Key Anatomic/Physiologic Issues and Imaging Findings/ yahoo.com) Techniques: The emphasis will be on clinical evaluation tests used by orthopedists and other clinicians, correlating with the Background Information: Glenohumeral joint injection is a MR findings for positive injuries to the specific region(s) being common procedure performed primarily in the outpatient setting . evaluated . Various techniques have been described in the past, the majority of which involve fluoroscopy and iodinated contrast agents . It Conclusion: While MR is the reference standard with regards to was only in the past 5-10 years that ultrasound emerged as a possible glenohumeral disease, sometimes subtle abnormalities practical alternative for accessing the shoulder . To our knowledge, can be missed by the radiologist . Interpreting radiologists should only a posterior approach using ultrasound guidance has been be aware of the types of physical examination techniques utilized described in the literature . Our purpose is to describe a safe and prior to MR imaging, so as to better understand the clinical and effective ultrasound-guided anterior approach using the rotator imaging correlation . cuff interval .

293 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Educational Goals/Teaching Points: There are several advan- ligament; and one patient with subluxation of the annular liga- tages to performing shoulder injections under ultrasound guid- ment to the level of the radiohumeral articulation . In ten cases, ance as opposed to the more traditional fluoroscopic techniques . the annular ligament injury was associated with other ligamen- Ultrasound tends to be faster and eliminates exposure to ionizing tous and/or osseous injuries within the elbow . radiation . It may be performed portably or in the office setting . It eliminates the need for iodinated contrast agents and the needle Conclusion: Isolated annular ligament injuries may occur more can be directly observed and manipulated in real time as it frequently than reported in the literature . The posterior attach- traverses the rotator cuff interval . Finally, patients tend to be ment of the annular ligament is most susceptible to injury . more comfortable on an ultrasound exam table as opposed to a Furthermore, isolated annular ligament injuries may be demon- hard fluoroscopy unit . strated by MRI of the elbow and possibly to better advantage with MR arthrography . Reports of isolated annular ligament tears Key Anatomic/Physiologic Issues and Imaging Findings/ without concomitant elbow pathology are rare in the radiology Techniques: The rotator cuff interval is created by the coracoid and orthopedic literature . In all but one reported case the annu- process of the scapula . It separates the supraspinatus and sub- lar ligament injury was not identified at the time of MRI but at scapularis tendons, contains the coracohumeral and superior subsequent arthroscopy . These lesions should be suspected in glenohumeral ligaments, and allows the long head of the biceps patients who present with snapping or clicking of the elbow . tendon to pass from the bicipital groove to it’s insertion on the Recognition of this entity and its clinical presentation may ena- superior glenoid . Our technique employs the use of a 5-12 meg- ble diagnosis at the time of imaging and potentially impact ahertz linear array transducer, depending on patient size and management . body habitus . With the patient in the supine, semirecumbent position, the affected shoulder is externally rotated to protect the biceps tendon . The shoulder is then prepped and draped in the E351. Cadaveric Elbow Allograft and Prosthetic Arthroplasty: usual aseptic fashion . The transducer is positioned anteriorly so Indications and Imaging Findings (CME Credit Available) that the coracoid process and medial aspect of the humeral head Tumyan, L.1; Chakarun, C.1; Itamura, J.1; Learch,T.2; White, E.1. are both visible . The articular cortex of the humeral head appears 1.University of Southern California-Keck School of Medicine, Los as a spherically curved echogenic line . After local anesthesia, a 20 Angeles, CA; 2. Cedars Sinai Medical Center, Los Angeles, CA to 22 gauge spinal needle is then advanced in to the gleno- Address correspondence to L. Tumyan ([email protected]) humeral joint space under direct visualization . Intra-articular injection of gadolinium is confirmed using loss of resistance tech- Background Information: The purpose of the exhibit is to nique and by directly observing adequate distension of the joint understand the role of radiologic studies in evaluating cadaveric capsule . The patient may then proceed to MR . allograft transplantation and prosthetic elbow arthroplasties, and to familiarize the radiologist with examples of both normal and Conclusion: Ultrasound-guided glenohumeral joint injection pathologic imaging findings in postoperative patients . The exhibit using the rotator cuff interval is a safe and effective alternative for will improve the relevance of radiology reporting of elbow MR arthrography that can be performed in the outpatient setting . pathology for surgical decision-making by discussing the findings in the language used by orthopedic surgeons .

E350. MR Imaging of Annular Ligament Injuries of the Educational Goals/Teaching Points: The exhibit will review Elbow: The Overlooked Isolated Annular Ligament Tear and present relevant elbow pathology that leads to elbow trans- Brouha, S.; Cardoso, F.; Pathria, M.; Resnick, D.; Chung, C. plantation or arthroplasty . Examples and cases of elbow arthro- University of California San Diego, San Diego, CA plasties including elbow transplantation, linked and unlinked Address correspondence to S. Brouha ([email protected]) arthroplasties, elbow arthroplasty revision, and radial head pros- thesis will be demonstrated . We will discuss and present imaging Objective: In this study, we review the normal MR appearance of findings of complications in elbow transplantations and arthro- the annular ligament and describe the MR appearance of annular plasties . ligament injuries . Key Anatomic/Physiologic Issues and Imaging Findings/ Materials and Methods: We reviewed all 336 elbow MR imag- Techniques: Prosthetic elbow surgery includes linked and ing reports from two institutions performed between January, unlinked arthroplasties, elbow arthroplasty revision, and radial 2006 and March, 2008 and one institution during 2007 to identi- head prosthetic replacement . The most common postoperative fy cases with annular ligament pathology . The selected cases complications include instability, polyethylene linear wear, osteol- were reviewed by two musculoskeletal-trained radiologists for ysis, loosening, infection, fracture, heterotopic ossification, and elbow pathology . In addition, the patient histories were reviewed failure of transplantation . to evaluate for symptoms including snapping of the elbow . Conclusion: Evolving surgical and reconstruction techniques for Results: We identified 15 MRI elbow studies in 14 patients with treatment of elbow pathology require the radiologist to become annular ligament pathology . Five studies in four patients demon- familiar with novel imaging findings associated with these proce- strated isolated annular ligament injuries without concurrent liga- dures . This presentation will include a complete discussion of mentous injuries of the elbow . All these patients encountered imaging studies in assessing appropriateness for surgery, proper either posterior elbow pain or snapping elbow . Pathology postoperative positioning, common and uncommon complica- encountered includes one patient with bilateral partial tears of tions of cadaveric elbow allografts and prosthetic arthroplasties . the annular ligament; two patients with isolated annular ligament injuries, including a rupture of the posterior band of the annular

294 El e c t r o n i c Ex h i b i t s : Musculoskeletal

E352. Sonographic Evaluation of the Painful Elbow Conclusion: Ultrasound is an excellent modality for evaluation of Kim, M.; Choo, H.; Lee, S. Inje University Pusan Paik Hospital, the normal and abnormal elbow . Busan, Korea Address correspondence to H. Choo ([email protected]) E354. Masses of the Hand Background Information: The elbow is an important synovial Killam, J.; Benitez, C. St. Luke’s Roosevelt Hospital, New York, NY hinge joint of the upper extremity and a common site of muscu- Address correspondence to J. Killam ([email protected]) loskeletal symptomatology, affecting all age groups . Elbow ultra- sound (US) has the advantage because it is cost-effective, widely Background Information: Masses of the hand are often recog- available, beautifully demonstrates superficial soft tissue struc- nized early by patients who encounter them during routine eve- tures, and it is able to perform a dynamic examination while ryday activities . Although radiographs should be the initial diag- obtaining patient feedback and . nostic study, MRI examinations are invariably used for further evaluation . The superior contrast resolution allows distinction of Educational Goals/Teaching Points: The goals of the exhibit various tissue types and the use of intravenous gadolinium pro- are to illustrate the sonographic anatomy of elbow, and describe vides information about vascularity and perfusion patterns . the various disorders to induce the painful elbows . Location is another important characteristic in assessment . As hand masses are not routinely encountered in clinical practice, it Key Anatomic/Physiologic Issues and Imaging Findings/ is necessary to be familiar with the above characteristics in order Techniques: This article describes the use of ultrasound in the to generate a reasonable differential diagnosis . evaluation of the elbow . First, normal US anatomy of elbow will be illustrated . Then, common pathologies about the elbow are Educational Goals/Teaching Points: The goals are to present a demonstrated, including tear of biceps tendon, common extensor review of hand anatomy, and describe imaging characteristics of tendon and flexor tendon, medial and lateral epicondylitis, cubital various masses including vascularity and enhancement patterns as tunnel syndrome, dislocation of ulnar nerve, olecranon bursitis, well as common locations . All hand masses are not neoplastic . inflammatory and infectious arthritis, and so on . In addition, spe- Etiologies are broadly divided into post-traumatic, related to cific imaging techniques and positions are described for optimum degenerative joint disease and other arthridities, and spontaneous . visualization of the various structures around the elbow . Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: There are variable diseases resulting in elbow pain Techniques: Cysts occur near joints and are related to degenera- and US is a valuable imaging tool for assessment of disorders of tive processes and ligament tears . A finger tip is a common loca- the elbow joint . tion of glomus tumors and inclusion cysts . Nerve sheath tumors and pseudoaneurysms occur in the region of the neurovascular bundles . E353. Ultrasound of the Elbow: Surface Anatomy, Common Pathology and Positioning of the Ultrasound Transducer Conclusion: Evaluation of hand masses requires intimate famili- (CME Credit Available) arity with the anatomy . Systematic evaluation of signal character- Fourgas, E.; Craig, J.; Bouffard, A.; van Holsbeeck, M. Henry Ford istics, location and clinical history allows the differential diagnosis Hospital, Detroit, MI to be narrowed . Many will ultimately require histologic evalua- Address correspondence to E. Fourgas ([email protected]) tion . In addition to providing information about the mass itself, the MRI provides valuable information to the surgeon for surgical Background Information: Ultrasound of the elbow is a nonin- planning related to involvement of structures around the mass . vasive modality for the diagnosis of joint, tendon, ligament and soft tissue pathology . It is a flexible, dynamic and low cost modality making it an excellent choice . E355. Hurt Hands: Fractures and Other Injuries (CME Credit Available) Educational Goals/Teaching Points: After completing this edu- Bush, L.; Gerson, R.; Chew, F.; Goodman, M.; Mulcahy, H. cational activity, the participant will understand the normal anat- University of Washington, Seattle, WA omy of the elbow as seen by ultrasound; be able to identify com- Address correspondence to L. Bush ([email protected]) mon elbow pathology by ultrasound, and will become familiar with optimal transducer positioning . Background Information: Interpreting injuries of the hand can be an intimidating task because of the complex anatomy, the Key Anatomic/Physiologic Issues and Imaging Findings/ intricate biomechanics, and the broad range of pathology . Injuries Techniques: Normal surface anatomy and appearance of the to the hand can also result in long-term dysfunction with emo- major structures of the elbow will be reviewed . Common pathol- tional and economic impact . It is important for radiologists to ogy around the elbow including long head of biceps and triceps recognize a variety of injury patterns and their appearance in tears, medial and lateral epicondylitis, tears of the anterior band multiple imaging modalities with awareness of features signifi- of the ulnar collateral ligament, olecranon bursitis, inflammatory cant to treatment options and urgency of triage . This educational arthritis and joint bodies will be reviewed . Some of the cases will exhibit demystifies this difficult region and presents an approach have MR correlation . Optimal positioning of the transducer will to accurately interpreting hand injuries in a variety of modalities be demonstrated and the corresponding normal anatomy will be to facilitate optimal and expedient patient care . displayed . The format will be didactic . The presentation will include images of the normal surface anatomy, common pathol- Educational Goals/Teaching Points: The objectives of this edu- ogy and optimal ultrasound transducer positioning . cational activity are for the participant to review the normal

295 El e c t r o n i c Ex h i b i t s : Musculoskeletal appearance of the hand; evaluate the relation of mechanism of mechanics of the thumb and first metacarpal; understand the trauma to patterns of injury; develop a pattern of assessing criti- advantages and limitations of various imaging modalities in eval- cal structures in the hand for injury; assess various cases of trau- uating thumb/first metacarpal pathology including radiography, matic injuries to the hand with a variety of imaging modalities, MRI and ultrasound; understand the basic technique of ultra- and appropriately emphasize findings that are of importance to sound of the thumb, and be able to review the imaging charac- optimizing patient treatment and triage . teristics of common and unusual pathology involving the thumb and first metacarpal including traumatic, neoplastic, infectious, Key Anatomic/Physiologic Issues and Imaging Findings/ inflammatory and vascular etiologies . Techniques: The normal appearance of osseous, articular, liga- mentous, musculotendinous, neurovascular, and soft tissue anat- omy of the hand are reviewed . Case examples with a multimo- E357. Radiological Evaluation of Partial (Functional) Wrist dality approach including radiographs, CT, ultrasound, and MRI Arthrodesis are used to illustrate the relationship of mechanism of trauma to Turecki, M.; Taljanovic, M.; Sheikh, S.; Sheppard, J.; Holden, D.; the pattern of injury . Critical injury findings that impact treatment Enoki, N. University of Arizona Health Sciences Center, Tucson, AZ options or necessitate urgent management are emphasized . Address correspondence to M. Turecki ([email protected])

Conclusion: This interactive computer-based educational exhibit Background Information: Partial wrist arthrodesis is performed presents an approach to interpretation of hand trauma to facili- to provide arthritic pain relief by eliminating movement in affect- tate recognition and description of a variety of injury patterns and ed joints while preserving maximal function of the wrist and emphasizes findings which impact treatment . Participants may hand . Other indications include previous tumor resection, spastic- take an interactive self-assessment module to facilitate and rein- ity, paralysis, or revision of prior unsuccessful arthrodesis . force their learning . Educational Goals/Teaching Points: We will attempt to famil- The views expressed in this manuscript are those of the authors iarize the reader with key points of the current surgical tech- and do not reflect the official policy or position of the Department niques and radiographic evaluation of partial wrist arthrodesis . of the Army, Department of Defense or the US Government. Current approaches to wrist arthrodesis include total (nonfunc- tional) arthrodesis which will not be further discussed here and partial or functional arthrodesis . Partial wrist arthrodesis is usually E356. Imaging of the Thumb and First Metacarpal: A achieved by combination of internal plates and screws which Multimodality Pictorial Review of Anatomy and Pathology have quickly replaced older techniques such as pin fixation, deco- With Emphasis on Musculoskeletal Ultrasound (CME Credit rtication, and corticocancellous bone grafts . Available) Friedkin, A.; Jacobson, J.; Livermore, J.; Brandon, C.; Girish, G.; Key Anatomic/Physiologic Issues and Imaging Findings/ Jebson, P. University of Michigan, Ypsilanti, MI Techniques: The most common types of partial wrist arthrodesis Address correspondence to A. Friedkin (aaron.friedkin@gmail. include scaphoid-trapezium-trapezoid, corticocancellous and com) scaphoid-capitate-lunate arthrodesis with variable screw fixation and two types of four corner fusion including the trapezium-trap- Background Information: Imaging of the thumb and first meta- ezoid-capitate-scaphoid and lunate-triquetral-capitate-hamate carpal warrants specific attention given the unique mechanics of arthrodesis with four corner compression plate and variable these structures and their importance in daily activities . Our goal screws fixation . Isolated dual carpal bone fusion such as capito- is to review thumb anatomy and demonstrate the imaging char- lunate may be used . Initial radiographic follow-up concentrates acteristics of thumb pathology, including traumatic, neoplastic, on hardware assessment and exclusion of infection, especially infectious, vascular, and inflammatory processes . Review of important in patients with postoperative pain . Subsequent stud- thumb anatomy will rely on both cadaveric dissection as well as ies evaluate for later complications including nonunion, fractures, imaging findings . pseudoarthrosis, hardware loosening or fracture, reflex sympa- thetic dystrophy, or impingement syndrome . Neuroma formation, Educational Goals/Teaching Points: The exhibit will include transient nerve palsy, tendon adhesions, or skin necrosis are anatomy and mechanics of the thumb and first metacarpal other less common complications . including examples of cadaveric dissection and imaging findings; imaging modalities of the thumb (limitations and advantages of Conclusion: The techniques of partial wrist arthrodesis are still radiographs, CT, MRI, ultrasound; indications for each modality evolving with controversies remaining as to which bones should and techniques of thumb/metacarpal ultrasound), and examples be fused to provide the best residual functional outcome . of thumb/metacarpal pathology with discussion of management . Radiologists should be familiar with the normal radiographic findings of partial wrist arthrodesis and their potential complica- Key Anatomic/Physiologic Issues and Imaging Findings/ tions . Techniques: Examples will focus on ultrasound, although radio- graphic and MRI correlation will be included . Trauma, neoplasms, infections, inflammation, and vascular malformations will be dis- cussed .

Conclusion: After reviewing the exhibit, the participant of this educational activity will understand the unique anatomy and

296 El e c t r o n i c Ex h i b i t s : Musculoskeletal

E358. Radiology of Carpal Trauma (CME Credit Available) tion of carpal bones . Carpal fusions, particularly of the scaphoid Goodman, M.; Bush, L.; Chew, F.; Mulcahy, H. University of and trapezium, were common in both groups . Washington, Seattle, WA Address correspondence to M. Goodman ([email protected] Conclusion: Carpal bone involvement anomalies (delay, dishar- ton.edu) mony and/or fusions) are frequent in Poland syndrome and can occur in patients with mild or severe hand involvement . This Background Information: Early diagnosis and treatment of car- characteristic of Poland syndrome has not been fully appreciated pal bone trauma is of paramount importance to avoid poor out- previously . comes and disability . The complex anatomy of the carpus and the importance of both bony and soft tissue structures pose chal- lenges for the radiologist . Different imaging modalities are E360. Classic and Alternative Approaches for Extremity employed for accurate and unambiguous diagnosis of carpal inju- Arthrography (CME Credit Available) ries . Postoperative evaluation is equally important because non- Hom, B.; Anderson, M.; Gaskin, C.; Fox, M.; Barr, M. University of anatomic reduction and positioning may lead to functionally disa- Virginia, Charlottesville, VA bling results . Address correspondence to B. Hom ([email protected])

Educational Goals/Teaching Points: The objectives of this edu- Background Information: Arthrography is commonly used prior cational activity are for the participant to learn the mechanisms to MR and CT to distend the joint capsule and allow for of traumatic carpal injuries; develop a systematic method for improved visualization of intra-articular structures . Contrast or interpreting diagnostic images of carpal injuries, and recognize saline arthrography improves diagnosis of labral tears, postopera- the different patterns of injury as demonstrated by imaging . tive meniscal tears, and ligamentous tears . It also allows for bet- ter assessment of hyaline cartilage defects, stability of osteochon- Key Anatomic/Physiologic Issues and Imaging Findings/ dral lesions, and the presence of loose bodies . Each of the major Techniques: Accurate interpretation of conventional radiographs, appendicular joints can be accessed by more than one approach, cross-sectional imaging and wrist arthrography coupled with and knowledge of the advantages and disadvantages of each is knowledge of critical factors that alter treatment decisions is important when performing these procedures . important for appropriate patient outcome . These factors include developing a systematic method of interpreting radiographs, CTs Educational Goals/Teaching Points: In this exhibit we will and MRI, knowing mechanisms of traumatic carpal injuries and review approaches to arthrography of each of the major appen- recognizing these mechanisms on imaging . Knowledge of mech- dicular joints including the shoulder, elbow, wrist, hip, knee and anisms also allows for appropriate imaging modality selection . ankle . The classic approach for each joint will be discussed fol- lowed by alternative approaches . We will discuss the advantages Conclusion: This computer-based educational exhibit reviews and potential disadvantages of each approach and when, in our radiology of traumatic carpal injuries so that the practicing radiol- clinical experience, one is preferred over another . ogist can recognize and accurately describe them . Cases are pre- sented interactively as unknowns so that participants may self-as- Key Anatomic/Physiologic Issues and Imaging Findings/ sess their knowledge . Techniques: The following will be discussed: shoulder (anterior, rotator cuff interval, posterior); elbow (lateral, posterior); wrist (distal radial ulnar joint, mid carpal, radiocarpal); hip (anterior, E359. The Carpal Bones in Poland Syndrome anterolateral); knee (anterior lateral, anterior medial, anterior), Friedman, T.; Reed, M.; Elliot, A. University of Manitoba, Winnipeg, and ankle (direct anterior, anterolateral) . Canada Address correspondence to T. Friedman ([email protected]) Conclusion: Arthrography is a useful technique in conjunc- tion with MR and CT for improved assessment of intra-articular Objective: The objective was to examine the carpal bones in structures . A knowledge of the spectrum of fluoroscopic Poland syndrome in local patients and patients from the litera- approaches to each joint is useful for providing the most efficient ture . and advantageous examination for a given clinical situation .

Materials and Methods: Hand radiographs from local patients and patients identified from the literature with confirmed Poland E361. Ultrasound Appearance of Metastatic and Recurrent syndrome were examined for evidence of carpal bone involve- Extremity Tumors with MR Correlation ment . Only cases with radiographs of adequate quality were Woodrow, A.; Jacobson, J.; Girish, G.; Dong, Q.; Jiang, Y.; Jamadar, included in the analysis . In total, seven local patients and 23 D. University of Michigan, Ann Arbor, MI patients from the literature were evaluated . Address correspondence to A. Woodrow ([email protected]. edu) Results: Of the 23 literature patients, 12 patients (52%) had abnormal findings . Of the abnormal patients, 4/12 (33%) had Background Information: New extremity masses in the patient carpal fusions, 8/12 (67%) showed disharmonious ossification status post removal of an extremity tumor present a difficult clini- between the carpal and tubular bones and 7/12 (58%) showed cal challenge . Ultrasound can be used as a primary and a com- delay of carpal ossification . Of the local cohort, three patients plementary modality to MR in the differentiation of recurrent or were too young to characterize carpal involvement . Of the four metastatic disease from benign postoperative changes . The pur- remaining patients, two (50%) had abnormal carpal morphology, pose of this educational exhibit is to review the sonographic 3/4 had disharmonious ossification and 4/4 had delay of ossifica- appearance of pathology proven recurrent and metastatic

297 El e c t r o n i c Ex h i b i t s : Musculoskeletal extremity tumors and compare and contrast these findings with E364. Imaging Features of Lucent Lesions of the Face: What the sonographic appearance of postsurgical changes after tumor Every Radiologist Must Know to Develop a Workable removal . Differential Diagnosis Jiang, J.; Daffner, R. Allegheny General Hospital, Pittsburgh, PA Educational Goals/Teaching Points: The goals are to review Address correspondence to J. Jiang ([email protected]) the ultrasound characteristics of metastatic and recurrent extrem- ity tumors; review the ultrasound characteristics of postsurgical Background Information: Radiologists frequently encounter changes in the extremity; review the ultrasound characteristics of dental and oral abnormalities . This exhibit will familiarize the primary extremity tumors; compare and contrast the above char- reader with a wide range of normal variant, benign and malig- acteristics; describe key ultrasound findings in differentiation of nant lucent lesions of the face with the aid of a variety of imag- metastatic/recurrent extremity tumors from postsurgical change, ing modalities, and define an approach to analyze the lesion and demonstrate correlation with MR imaging . based on imaging features and forming a differential diagnosis .

Key Anatomic/Physiologic Issues and Imaging Findings/ Educational Goals/Teaching Points: The exhibit will include Techniques: Metastatic and recurrent extremity tumors demon- normal anatomy of the face emphasizing the mandible and the strate ultrasound findings such as a discrete mass, hypoecho- oral cavity . General imaging characteristics associated with lucent genicity and hypervascularity . Lymphoma may appear as a hypoe- lesions are illustrated . Clear case examples of normal variant, choic infiltrative mass . Benign postsurgical ultrasound findings developmental, acquired including cysts, infectious, inflammatory, after tumor removal include lack of a defined mass, heterogenei- benign and malignant neoplasms, metabolic and traumatic ty, hypoechogenicity, and variable hyperemia . Although findings lucent lesions are explored . Imaging appearances and common in these two groups demonstrate significant overlap, findings of a pitfalls regarding benign and its “evil twin” lesions are discussed . discrete mass and hypervascularity tend to correlate more strong- ly with recurrent or metastatic disease . Primary tumors demon- Key Anatomic/Physiologic Issues and Imaging Findings/ strate findings similar to metastatic disease, notably a discrete Techniques: Imaging modalities employed include Panelipse, CT, mass, hypoechogenicity, and hypervascularity . MRI and pathology . Detailed illustrations and explanation of the dental and oral abnormalities are provided . Common pitfalls and Conclusion: Although ultrasound findings in pathologically prov- “evil twins” are provided side by side for detailed comparison . en recurrent and metastatic extremity tumors and ultrasound findings in benign postsurgical changes demonstrate significant Conclusion: The same principles for lucent bone lesions else- overlap, ultrasound can be a valuable modality in evaluating a where can be applied to the face . Familiarity with a lesion’s loca- new mass in a patient status post surgical removal of an extremi- tion, epicenter, borders, internal contents, and its effect on adja- ty tumor . cent structures can provide the radiologists with a tremendous amount of information at reaching an accurate diagnosis and ultimately effecting patient management . E363. Sonographic Evaluation in the Clinical Setting of Xiphoid Area Pain and/or Palpable Mass Macatol, J.; Fessell, D.; Jamadar, D.; Girish, G.; Dong, Q.; E365. CT and MRI Findings of Chondroblastoma of the Jacobson, J. University of Michigan, Ann Arbor, MI Temporal Bone in 31 Patients With Pathologic Correlation Address correspondence to J. Macatol ([email protected]) Brickner, M.; Glazebrook, K.; Inwards, C. Mayo Clinic, St. Louis Park, MN Objective: The objective was to investigate the clinical entity of Address correspondence to M. Brickner ([email protected]) pain and/or palpable mass in the region of the xiphoid by ultra- sound and discuss the sonographic findings as well as spectrum Objective: The purpose is to describe and characterize the radi- of possible diagnoses . ologic appearance of chondroblastoma of the temporal bone through CT and MRI . Materials and Methods: This was a retrospective review of 31 consecutive patients whom were evaluated with ultrasound for Materials and Methods: One musculoskeletal radiologist and xiphoid area complaints from 2002 through 2008 . Sonographic one musculoskeletal fellow retrospectively reviewed 31 patholog- findings were reviewed . Clinical/imaging follow-up was also ically proven cases of chondroblastoma of the temporal bone . reviewed, when available . Radiologic studies reviewed by consensus included CT (n=31) and MRI (n=16) . Evaluation included patient’s age and sex . CT Results: Of the 31 patients, the spectrum of diagnoses include: evaluation included size, location, expansion, matrix including the lipoma, ventral hernia, variant shape of the xiphoid, thickening of presence of mineralization, aggression, and presence of a soft tis- adjacent fascia, rectus abdominus injury, and normal appearing sue mass . MRI evaluation included intrinsic T1 and T2 signal xiphoid . Seven patients had follow-up CT imaging for correlation . along with the presence of contrast enhancement .

Conclusion: The clinical entity of xiphoid area palpable mass Results: Chondroblastoma of the temporal bone patients includ- and/or pain is not uncommon . No aggressive or malignant mass- ed 22 males and nine females with age ranges of 27-81 years es were found in this series . This data supports that this clinical old . The average tumor size was 3 0. cm x 3 .0 cm and located entity may be considered a “pseudo-mass” . predominately in the squamosal portion of the temporal bone (n=26 or 84%) . Bony expansion of the tumor was identified in the vast majority of cases (n=29 or 94%) with a lytic (n=29 or 94%) matrix and presence of some mineralization (n=24 or

298 El e c t r o n i c Ex h i b i t s : Musculoskeletal

77%) . Over half of the tumors were aggressive in nature (n=18 infection (osteomyelitis, abscess, odontogenic infection, necrotiz- or 58%) and had an associated soft tissue mass (n=16 or 52%) . ing fascitis); bisphosphonate osteonecrosis; sialolithiasis; tempo- Of the cases with soft tissue involvement, 14/16 had a soft tissue romandibular joint disorders and replacement, and trauma . mass or soft tissue thickening within the external auditory canal . Most lesions had predominately low signal characteristics on Conclusion: In summary, proper characterization of jaw patholo- both T1-weighted imaging (90%) and T2-weighted imaging gy is essential to ensure appropriate patient care and reduce (67%) when MRI images were included . Most tumors with post- morbidity . Imaging plays a key role in the characterization of a contrast T1-weighted imaging displayed some degree of variety of jaw lesions and radiologists must be familiar with these enhancement (93%) . imaging findings .

Conclusion: Typical CT findings of chondroblastoma of the tem- poral bone include an expansile, lytic tumor with the presence of E367. The Cortical Groove Sign: A Newly Described Finding mineralization located predominately in the squamosal portion of Associated With Osteoid Osteomas the temporal bone . External auditory canal involvement was fre- Liu, P.; Kujak, J.; Roberts, C. Mayo Clinic, Scottsdale, AZ quently identified in cases in which a soft tissue mass was Address correspondence to P. Liu ([email protected]) present . MRI findings typically demonstrate a mass with low sig- nal on T1- and T2-weighted images with some degree of Objective: Osteoid osteomas have been shown on CT, MR enhancement . nuclear bone scintigraphy and arteriography to be hypervascular tumors . We introduce a new finding seen on CT exams of osteoid osteomas, the “cortical groove” sign, consisting of one or more E366. Imaging Characteristics of Mandibular Lesions (CME thin curvilinear or serpiginous lucencies coursing through adja- Credit Available) cent bone cortex into the tumor nidus . These lucencies have the Meyer, K.1; Bancroft, L.2; Dietrich, T.3; Berquist, T.1; Kransdorf, M.1; appearance of vascular grooves containing vessels feeding these Peterson, J.1 1. Mayo Clinic, Jacksonville, Jacksonville, FL; 2. Florida hypervascular tumors . We performed this study to determine the Hospital, Orlando, FL; 3. University of Louisville, Louisville, KY sensitivity and specificity of the cortical groove sign for osteoid Address correspondence to K. Meyer ([email protected]) osteomas .

Background Information: Jaw pathology is common, yet it is Materials and Methods: In this IRB approved retrospective not encountered by the radiologist on a daily basis . It is impor- study, radiology records were searched to identify cases of patho- tant for radiologists to recognize jaw pathology to ensure appro- logically proven osteoid osteomas imaged with CT over the past priate, timely patient care . A common site of complaint is the ten years . Forty-one cases were identified . For control cases, radi- temporomandibular joint (TMJ) . MRI can evaluate displaced ology records were searched to identify 29 bone lesion biopsy disks, inflammation and osteoarthritis . Infection and trauma are cases with pathologic diagnoses . Two musculoskeletal radiolo- typically diagnosed based on clinical findings . However, imaging gists performed independent, blinded review of these CT exams, studies are usually needed to assess the extent of disease as well grading for the appearance of the cortical groove sign . as to aid in treatment planning . Imaging studies may not provide Interobserver agreement was calculated, and Fisher’s exact test a specific diagnosis, yet they should narrow the differential and was used to examine for statistical significance . guide further work-up . Additionally, jaw pathology may present in a nonspecific manner, making imaging of the utmost importance Results: For readers 1 and 2 respectively, sensitivity of the corti- in elucidating the etiology of the patient’s symptoms . cal groove sign for detection of osteoid osteoma was 0 .74 and 0 .76; specificity was 0 .97 and 0 .90 . Using Fisher’s exact test, Educational Goals/Teaching Points: After review of this educa- p<0 0001. for both readers . Interobserver agreement was very tional exhibit, viewers will be able to recognize the indications good, with kappa=0 85. . and appropriate imaging studies for various mandibular lesions (radiographs as first line imaging, CT for evaluation of osseous Conclusion: The cortical groove sign is a moderately sensitive lesions, MRI for characterization of soft tissue lesions, and CT 3D but very specific CT finding for osteoid osteomas . Our findings surfacing reformats for surgical planning); describe the imaging correlate with recently reported histologic findings of multiple findings of relatively common jaw pathology including, but not prominent arteries and arterioles supplying these hypervascular limited to differentiation of benign vs . malignant tumor character- tumors . istics, infectious processes (abscesses, osteomyelitis, odontogenic infections, necrotizing fascitis), osteonecrosis, TMJ disorders and expected trauma patterns to help to avoid overlooking occult E368. Soft Tissue Calcifications: What Am I Looking At and fractures; formulate a differential diagnosis based on clinical What Should I Do About It? (CME Credit Available) presentation and imaging characteristics, and understand appro- Callahan, B.; Wu, J.; Hall, F.; Hochman, M. Beth Israel Deaconess priate treatment options (simple excision, excision with recon- Medical Center, Boston, MA struction, joint repair with or without joint prosthesis and surgical Address correspondence to B. Callahan (bcallaha@caregroup. debridement) . harvard.edu)

Key Anatomic/Physiologic Issues and Imaging Findings/ Background Information: Soft tissue calcifications are frequent- Techniques: This exhibit will address the anatomy, physiology, ly encountered during routine radiographic evaluation and are clinical imaging, characteristic imaging, suggested imaging often associated with local underlying pathology, systemic dis- modalities, and surgical treatment for neoplasms (benign and ease, or, occasionally, malignancy . Radiographs often demon- malignant); congenital disorders (Treacher-Collins, cherubism); strate distinct imaging features for different types of soft tissue

299 El e c t r o n i c Ex h i b i t s : Musculoskeletal calcification . Familiarity with characteristic features of soft tissue fascial lipoma was reported as the most likely diagnosis on sono- calcifications can help the radiologist generate more accurate — graphic examination . and more clinically relevant — differential diagnoses . Conclusion: Although the features of subfascial lipoma are more Educational Goals/Teaching Points: The exhibit will include a variable than those reported for subcutaneous lipomas, the pres- discussion of calcification vs . ossification and etiology and com- ence of thin internal echoes in conjunction with other less specif- position of different types of soft tissue calcification; presentation ic features should enable a correct diagnosis . of a spectrum of illustrative cases, with emphasis on distinctive imaging characteristics, and a discussion of clinical implications of the various forms of soft tissue calcification, including the pres- E370. Acoustoelastography of the Tendon: Applying a New ence of local pathology, systemic disease, and potential malig- Method for Evaluating Tissue Property and Deformation of nancy . It will discuss an analytic algorithm for assessment of soft the Musculoskeletal System tissue calcification or ossification, and provide recommendations Lee, K.; Kobayashi, H.; Vanderby, R. University of Wisconsin- for tailored work-up of findings that may be indicative of system- Madison, Madison, WI ic disease or tumor . Address correspondence to K. Lee ([email protected])

Key Anatomic/Physiologic Issues and Imaging Findings/ Objective: Diagnosing tendon or ligament injury can be a diffi- Techniques: The exhibit will review the spectrum of soft tissue cult task despite recent advances in . Ultrasound calcifications and their imaging (predominantly radiographic) has distinctive advantages over other imaging modalities (no appearance . The role of secondary findings and additional imag- radiation, portability, low cost, accessibility), but its musculoskele- ing work-up will be addressed . It will discuss the importance of tal use has been limited, particularly in the United States . recognizing atypical and or aggressive features of these entities, Innovative developments in ultrasound technology may expand and describe the pathophysiology and underlying biochemical diagnostic capabilities of musculoskeletal ultrasound and thereby perturbations leading to these various manifestations . increase its usage . The goal of this scientific exhibit is to intro- duce a new method that evaluates the tissue mechanical proper- Conclusion: A broad spectrum of soft tissue pathologies demon- ties of a porcine tendon using A-mode ultrasound . strates calcification . This exhibit will offer to help readers develop an approach to the radiographic evaluation of soft tissue calcifi- Materials and Methods: Our research group has developed an cations and heighten awareness regarding soft calcifications that innovative ultrasound wave analysis method termed “acoustoe- are indicative of systemic disease or malignancy . lastography ”. It is based on a mathematical theory called acous- toelasticity (AE) that relates mechanical properties to wave prop- agation (acoustic) characteristics in a deformed medium . The E369. Sonographic Features of Subfascial Lipomas concept of AE can be envisioned with a guitar string . When the Paunipagar, B.; Griffith, J. Chinese University of Hong Kong, New string is stretched, a geometric change (reduction in string diam- Territories, Hong Kong eter) and an acoustic change occurs (pitch increases), which are Address correspondence to B. Paunipagar ([email protected]) inter-related . AE was never applied to biological tissues, although this wave velocity change has been observed in stretched animal Objective: The objective was to describe the sonographic fea- tendons . We measured reflected echo magnitude using an tures of subfascial lipomas . A-mode 2 25. MHz Olympus-NDT V323-SU ultrasound device from stretched porcine flexor tendons in vitro (n=8) . Given a Materials and Methods: This was a retrospective review of measured reflected echo magnitude, the reflection coefficient sonographic features of 60 subfascial lipomas in 60 patients (41 was evaluated as the magnitude ratio of the reflected echo to the females, 19 males, mean age 46 .5, range 16-77 years) seen over incident echo . Tendon stiffness in the transverse direction was an eight-year period (1998–2006) . Features evaluated were loca- evaluated from the reflection coefficient . In order to remove the tion, size, shape, marginal definition, internal echogenicity, influence of variation in tissue density, normalized tendon stiff- including the presence of intermingled muscle fibers and linear ness was evaluated as the ratio of stiffness in a deformed state internal echoes, acoustic transmission and vascularity . to stiffness in a nondeformed state . Confirmation was made histologically in 33 (55%) cases and by typical MRI appearances in 27 (45%) cases . MRI proceeded Results: We have found that the normalized stiffness of the por- sonographic examination in only one patient . cine flexor tendon is linearly related to applied force (mean slope—4 .6 x 10-4 SD—8 .1 x 10-5) . That is, as the tendon was Results: Of 60 subfascial lipomas, location was supramuscular stretched, a predictable measure of increasing stiffness could be (7%), intermuscular (27%), intramuscular (56%) or submuscular obtained . Wave velocity increased as the flexor tendon was (7%), others (3%) . Maximum diameter ranged from 1 cm to 15 stretched (increased stiffness), which can also be correlated with cm . Shape was fusiform in seven (12%), rounded in 25 (42%), its echogenicity . oblong in 20 (33%) or geographical in eight (13%) . Margin was well-defined in 48 (80 %) or ill-defined in 12 (20%) . Main lesion Conclusion: Acoustoelastography is a new application that can echogenicity was hypoechoic to muscle in 14 (23%), isoechoic in evaluate tissue mechanical properties of a tendon, which has 13 (22%) or hyperechoic in 37 (55%) . Linear internal echoes promising potential in enhancing diagnostic musculoskeletal were present in 59 (98%) . Acoustic transmission compared to ultrasound . Future studies will use B-mode evaluation . muscle was increased in 24 (40 %) . Twenty (33 %) lipomas revealed mild internal vascularity, eight (13 %) minimal internal vascularity and 36 (60%) no internal vascularity . In all cases sub-

300 El e c t r o n i c Ex h i b i t s : Musculoskeletal

E371. You Ache, Therefore I Scan: The Use of Ultrasound for Conclusion: Image-guided techniques can be used in the diag- Rheumatologic Disorders nosis and treatment of bursitis . Familiarity with the normal and Hoots, J.1; Shepherd, S.1; Strauss, D.2; Allison, S.1 1. Georgetown abnormal appearances of bursae will enable radiologists to cor- University Medical Center, Washington, DC; 2. No Institutional rectly identify bursal pathology and differentiate it from other Affiliation entities . Address correspondence to J. Hoots ([email protected])

Background Information: Musculoskeletal ultrasound is an E373. Imaging Features of Hemophilic Arthropathy (CME underutilized modality in evaluating rheumatologic disorders . The Credit Available) purpose of the exhibit it to review pathologic findings in rheuma- Brennan, I.; Murphy, G.; McEniff, N. St. James’s Hospital, Dublin, tologic disorders; demonstrate the sonographic appearance of Ireland these findings, and demonstrate the utility of ultrasound in evalu- Address correspondence to I. Brennan ([email protected]) ating rheumatologic disorders . Background Information: Deficiency of factor VIII or IX leads to Educational Goals/Teaching Points: The exhibit will include the clinical conditions of Hemophilia A and B respectively . Such rheumatologic disorders present with joint pathology; types of patients are prone to recurrent joint hemorrhage leading initially joint pathology (effusions and synovitis); sonographic features of to joint effusion and synovial proliferation . Late sequelae include joint pathology, and other applications of ultrasound (joint aspi- joint deformity, contracture and degenerative arthritis . ration, biopsy, injections) . Hemophilia affects 1 in 5000 Irish men with hemarthrosis occur- ring in 75-90% . Up to 50% of patients will progress to develop Conclusion: Ultrasound may be used to detect and diagnose permanent joint deformity . joint pathology associated with rheumatologic disease . Ultrasound is a cost effective, efficient modality in assessing dis- Educational Goals/Teaching Points: The goals are to describe ease activity in patients with rheumatologic disease . Ultrasound the radiographic appearance of early and established hemophilic may also provide additional diagnostic and treatment capabilities arthropathy in a variety of anatomical locations and to compare in assisting with joint aspiration, synovial biopsy and tendon plain radiography and MRI in the assessment and classification of injection in patients with rheumatologic disease . joint disease progression and treatment response .

Materials and Methods: Imaging from patients registered at the E372. Bursae, Bursae, Everywhere: A Radiologist’s Guide to National Centre for Hereditary Coagulation Disorders (NCHCD) Bursal Anatomy, Imaging, and Image-Guided Intervention incorporating the National Haemophilia Centre based in St (CME Credit Available) James’s hospital were reviewed (n=236 cases ) . Plain radiograph Melenevsky, Y.1; Newman, J.2; Perry, L.1; Wu, J.1; Hochman, M.1 and MR cases demonstrating the full spectrum of joint disease 1. Beth Israel Deaconess Medical Center, Boston, MA; 2. New were identified . Examples illustrating the established Arnold- England Baptist Hospital, Boston, MA Hilgartner classification system were noted . Address correspondence to Y. Melenevsky ([email protected]) Conclusion: Hemophilia is an important cause of potentially Background Information: Bursitis is a common cause of muscu- debilitating joint disease in young people . Knowledge of the loskeletal pathology, and can be a manifestation of an injury or sys- plain film and MR features of early and late hemophilic arthropa- temic disease . We will review bursal anatomy, function, and pathol- thy is essential to enable timely identification and monitoring of ogy using radiography, bursography, sonography, CT and MRI . this disease process .

Educational Goals/Teaching Points: The goals are to familiar- ize the reader with bursal anatomy and function; outline imaging E374. Dual-Energy CT for Evaluation of Gout characteristics of normal bursae throughout the body; describe Black, D.; Glazebrook, K.; Michet, C.; Berger, R.; Kavros, S.; common and uncommon bursal pathology, and provide an over- McCollough, C. Mayo Clinic, Rochester, MN view of common image-guided diagnostic and therapeutic bursal Address correspondence to K. Glazebrook (glazebrook.katrina@ interventions . mayo.edu)

Key Anatomic/Physiologic Issues and Imaging Findings/ Objective: The objective was to evaluate the technique of dual- Techniques: Bursae are small spaces lined by the synovium, typi- energy CT (DECT) scanning in demonstrating uric acid crystals in cally interposed between bony surfaces and ligaments or ten- the extremities of patients with inflammatory arthropathies . dons and may communicate with the joint . Usually bursae con- tain a small amount of fluid, alleviating friction between surfaces . Materials and Methods: Fifteen patients with inflammatory Normal bursae are not seen on radiographs, trace fluid can be arthropathies were scanned using the DECT scanner . Eleven detected by cross-sectional modalities . MR is superior in evalua- ankles and feet and four hands and wrists were scanned . There tion of bursal pathology and extent of soft tissue inflammation; were seven males and eight females with age range of 38 to 80, sonography offers advantages of real-time exam, availability and mean age of 63 years . All patients were clinically suspected of lower cost, but can be operator dependent . Bursitis can mimic having gout . DECT scanners have two, orthogonal X-ray tube/ other entities; imaging can provide valuable information in addi- detector array pairs . This design allows simultaneous acquisi- tion to clinical findings . Imaging may be used to guide diagnostic tion of the 80kVp and 140 kVp data sets used in dual energy needle aspiration of bursal fluid in bursitis . Intrabursal glucocorti- processing . The use of a different kVp for each tube exploits the coid injections can be utilized in the management of bursitis . kV-dependent nature of CT numbers, allowing differentiation of

301 El e c t r o n i c Ex h i b i t s : Musculoskeletal materials having different effective atomic numbers . Off line post- Conclusion: A systematic approach to the arthridities is essential processing was performed using a commercial software program for accurate diagnosis . We suggest this approach be considered . to create material selective images, where uric acid crystals were color coded as green and calcium as pink . E376. Imaging Characteristics of Skeletal Coccidioidomycosis Results: Eight patients had dual source CT scans positive for uric (CME Credit Available) acid crystals . Of these, six patients had longstanding tophaceous Kujak, J.; Lorans, R.; Chivers, S.; Liu, P. Mayo Clinic, Scottsdale, AZ gout, two of whom were participating in a polyethylene glycol Address correspondence to R. Lorans ([email protected]) uricase study for treatment of symptomatic tophaceous gout . In the remaining two patients, one patient had insufficient fluid on Background Information: Coccidioiodomycosis infection is joint aspiration to assess for uric acid crystals . She was treated for caused by a dimorphic fungus (coccidioides immitis) which lives gout following the positive DECT with clinical improvement . The in the soil of semiarid locations and is endemic to the American other patient, diagnosed as seronegative arthritis at an outside southwest, Mexico and South America . Exposure to the fungus is institution, was treated for gout following the positive DECT scan usually through inhalation and when symptomatic, most usually with clinical improvement . Seven cases were negative for uric causes a flu-like illness with pulmonary and systemic symptoms acid crystals on DECT scans . Two patients with hyperuricemia had also known as “valley fever” . Infection of the bone by this organ- joint aspirations with no uric acid crystals seen . One patient had ism is a relatively infrequent occurrence . Our purpose is to present extensive periarticular calcification seen on the DECT . She was the imaging features of several cases of pathologically proven thought to have calcium pyrophosphate deposition from chronic musculoskeletal and isolated soft tissue coccidioidomycosis . renal failure . One patient had an ankle joint aspiration negative for uric acid three months before the negative DECT scan . Educational Goals/Teaching Points: This educational exhibit Clinically, the remaining three patients were felt to have a flare of reviews the clinical presentation, demographics and musculoskel- seronegative arthritis following the negative DECT exam . etal imaging features of coccidioidomycosis so that the practicing radiologist can recognize this entity more readily in the appropri- Conclusion: DECT scanning appears to be a very useful tech- ate clinical context and place it in the differential diagnosis . In nique to noninvasively demonstrate uric acid deposition in today’s mobile society, the ease of international travel and travel patients with gout . A negative DECT appears to have a high nega- to endemic locations in the American southwest emphasizes the tive predictive value for gout in our small, pilot series . need to increase awareness and diagnostic consideration of this infection, especially in nonendemic areas . The objectives of this educational activity are for the participant to learn the various E375. Approach to Arthritis: ABC’s and Beyond radiologic features of musculoskeletal and soft tissue coccidioid- Rehani, B.; Wissman, R. University of Cincinnati, West Chester, OH omycosis infection; review the clinical presentation and demo- Address correspondence to R. Wissman (wissmaRD@healthall. graphics of patients with coccidioidomycosis infection, and to com) become more aware of this entity and consider the diagnosis in patients who have traveled to endemic areas . Background Information: Learning the arthridities is challeng- ing and sometimes confusing . There are a myriad of arthridities Key Anatomic/Physiologic Issues and Imaging Findings/ that can produce a host of radiographic findings . Generating a Techniques: There are a broad range of appearances of muscu- reasonable differential requires a systematic approach . Therefore loskeletal coccidioidomycosis and it can affect both the axial and we propose an approach to arthritis which categorizes arthridities appendicular skeleton . It may mimic inflammatory arthritis, into three categorizes- hypertrophic, inflammatory and deposition osteomyelitis, myeloma, sarcoma and pigmented villonodular diseases . synovitis . In our series, only 29% of patients were immunocom- promised and close to half of the patients presented with a sys- Educational Goals/Teaching Points: The goals are to review an temic illness . approach to the radiographic findings which has previously been described as the “ABC’S” of arthritis; use the radiographic find- Conclusion: As the imaging features of musculoskeletal coccidio- ings to categorize arthritis into one of three categories- hyper- idomycosis infection are nonspecific, this diagnosis should be trophic, inflammatory and deposition diseases; suggest ways to considered in patients with recent travel to endemic areas who differentiate seronegative arthridities from rheumatoid arthritis; present with bone/joint erosion, destruction or mass-like lesions . suggest ways to differentiate inflammatory arthritis from deposi- tion diseases, and suggest a simple method to remember the arthridities in each category . E377. Whole-Bone Osteomyelitis: Imaging Findings With Pathologic Correlation Key Anatomic/Physiologic Issues and Imaging Findings/ Roberts, K.; Simoncini, A.; Hollister, A.; Primeaux, T.; Rowell, A.; Techniques: Hypertrophic arthridities such as osteoarthritis and Sessions, D. Louisiana State University Health Sciences Center- diffuse idiopathic skeletal hyperostosis predominantly produce Shreveport, Shreveport, LA bone or osteophytes . Inflammatory arthridities such as rheuma- Address correspondence to K. Roberts ([email protected]) toid arthritis and infection produce early joint space narrowing and erosions often with little or no bone production . Deposition Background Information: Very few cases of whole-bone osteo- diseases such as pigmented villonodular synovitis, gout and other myelitis are described in the current literature . Submitted for crystal deposition diseases, often spare the joint space until late presentation are several cases of whole-bone osteomyelitis col- in the disease . lected over the last three years at our institution . This exhibit will showcase the MRI and radiographic imaging findings of this enti-

302 El e c t r o n i c Ex h i b i t s : Musculoskeletal ty along with pathologic correlation when possible . Clinical corre- Key Anatomic/Physiologic Issues and Imaging Findings/ lation as well as surgical and medical management will be out- Techniques: Traditionally, conventional radiography has been the lined in a case-by-case format . Follow-up images documenting mainstay in the imaging evaluation of Paget disease affecting the outcome of these rare cases will be presented when available . skeleton . Because CT may provide superior cortical and trabecu- lar detail and better depiction of osseous deformity (i e. . bowing) Educational Goals/Teaching Points: Osteomyelitis rarely affects it has been helpful in evaluating pagetic bone . MR imaging, the entirety of the long bone . Well-planned MRI protocols are owing to its exquisite soft tissue resolution and multiplanar imag- highly sensitive and specific in diagnosing the extent of osteomy- ing capabilities, can facilitate early and accurate diagnosis of elitis . Therapeutic management of whole-bone osteomyelitis is musculoskeletal complications, including osseous deformity, frac- heavily dependant upon the findings reported from radiographic ture, spinal stenosis, neoplastic degeneration, and osteoarthrosis . imaging . Finally, radionuclide scanning is well suited for defining the extent and activity of polyostotic disease especially in those sites Key Anatomic/Physiologic Issues and Imaging Findings/ with overlapping structures . Techniques: Multimodality imaging findings will be displayed in an electronic format, providing pathologic correlation when Conclusion: Recognition of the key imaging features of Paget possible . disease as derived from different imaging methods, coupled with information about the site or distribution of lesions, allows pro- Conclusion: Osteomyelitis of the entire long bone presents spective diagnosis of the disease and its associated musculoskel- certain diagnostic and therapeutic challenges which will be etal complications and can preclude biopsy . addressed in this educational exhibit . The clinician’s decision to pursue surgical vs . medical management in these cases is often impacted heavily by radiographic imaging findings . As very few E379. Surface Lesions of Bone–What to Do With Them cases have been described, this exhibit will serve to provide an Malhotra, A.; Dhillon, G.; Cesarz, M.; Seo, G.; Monu, J. University overview of the clinical and radiologic manifestations of this con- of Rochester, Rochester, NY dition . Address correspondence to J. Monu ([email protected] ter.edu)

E378. Spectrum of Imaging Findings in Paget Disease of Background Information: Many bone neoplasms occur either Bone and its Musculoskeletal Complications (CME Credit in the medullary space or cortex of bone . Lesions occurring on Available) the surface of bone may pose a diagnostic dilemma as it may be Theodorou, D.1; Theodorou, S.1; Kakitsubata, Y.2; Tsampoulas, difficult to decide the site of origin and hence the true nature of C.3 1. University of California, San Diego; San Diego, CA; 2. the lesion . Miyazaki Shakaihoken Hospital, Miyazaki, Japan; 3. University of Ioannina, Greece, Ioannina, Greece Educational Goals/Teaching Points: The goals are to provide Address correspondence to S. Theodorou (rjtheodorou@hotmail. a simple and organized approach way to analyze surface neo- com) plasm of bone; differentiate lesions that occur in proximity of bone from those that are intimately related to surface of bone, Background Information: Paget disease, or osteitis deformans, and have a working knowledge of the more common surface is a chronic skeletal disorder characterized by exaggerated and lesions of bone and their management . abnormal bone remodeling . It is the second most common bone disease after osteoporosis that affects the elderly in the United Key Anatomic/Physiologic Issues and Imaging Findings/ States . Paget disease of bone demonstrates a plethora of imag- Techniques: Selected images from our radiology data bank will ing patterns and variable appearances related to the pathologic be used to illustrate the usual features of surface neoplasm of stage of the disease . In the initial or active phase there is well bone . Correlative pathology images will be presented to buttress defined osteolysis in the skull (osteoporosis circumscripta) or the diagnoses . The differential diagnoses for the various lesions subchondral bone (blade-of-grass appearance), in the appendic- presented will be discussed and key diagnostic imaging and his- ular skeleton . In the mixed phase of disease, characteristic topathologic features will be highlighted . Management of the var- trabecular and cortical thickening (i e. ,. picture frame vertebra) ious disease entities will be addressed using illustrative cases . occurs in conjunction with bone enlargement; and, in the late or inactive phase of Paget’s there is predominant bone sclerosis (i e. ,. Conclusion: Surface neoplasms of bone are not uncommon . An ivory vertebra) . Despite the development of new therapies that organized and informed analysis of the images will frequently may diminish morbidity, patients with Paget are at risk of devel- enable an accurate diagnosis . oping various musculoskeletal complications .

Educational Goals/Teaching Points: In this educational exhibit, E380. Applications of SPECT-CT in Bone Imaging we revisit Paget disease of bone and illustrate the gamut of Yilmaz, Z.; Brown, R.; Frey, K. University of Michigan, Ann Arbor, MI imaging findings associated with this skeletal disorder . Although Address correspondence to R. Brown ([email protected]) we emphasize the radiographic appearance of Paget disease, a multimodality approach including scintigraphy, CT, and MR imag- Background Information: Nuclear scintigraphy is a highly sensi- ing is employed . Overall, this exhibit illustrates the imaging char- tive technique for the detection of bone pathology, however, it acteristics of Paget disease of bone, both uncomplicated and lacks specificity . Correlation with anatomic imaging can be useful complicated . in improving the diagnostic accuracy of the study . This exhibit

303 El e c t r o n i c Ex h i b i t s : Musculoskeletal demonstrates clinical examples where hybrid imaging improves ture-dislocation of spine and esophageal or tracheal rupture . the detection and characterization of bone pathology . Fractures that occur together are calcaneus and thoracolumbar spine, femoral shaft and hip fracture dislocation, tibia and hip Educational Goals/Teaching Points: The goals are for the par- dislocation, pelvis and sacrum or sacroiliac joint dislocation, chest ticipant in this educational activity to learn how fusion imaging wall and scapula, spine and sternum, and fracture-dislocation of can improve the diagnostic accuracy of nuclear scintigraphy; gain spine and costovertebral joint . Fractures-soft tissue dyads include a better understanding of what specific questions are best Segond fracture and anterior cruciate ligament (ACL) tear, arcuate answered with fusion imaging, and gain a better understanding sign and cruciate ligament rupture, osteochondral fracture of the of what CT protocols are used for evaluating bone pathology in patella and medial patellofemoral ligament tear, kissing bone fusion imaging . contusions in ACL rupture, kissing bone contusions in posterior cruciate ligament tear, orbital blow-out fracture entrapping inferi- Key Anatomic/Physiologic Issues and Imaging Findings/ or rectus muscle, ankle fracture and superior peroneal retinacu- Techniques: The exhibit demonstrates the problem solving capa- lum avulsion resulting in peroneal tendon subluxation, and ankle bilities of SPECT-CT in pathology that are subtle, occult or inde- fracture entrapping ankle tendon . Fractures-dislocation dyads terminate on standard planar imaging . Examples of fractures, include Monteggia, Galeazzi, Essex-Lopresti and Maisonneuve osteochondral injuries, osteomyelitis, avascular necrosis, metas- fracture dislocation . tases and degenerative changes simulating disease are demon- strated . The utility of viewing studies in a fusion mode is dis- Conclusion: Certain traumatic lesions occur together due to the cussed . mechanism of injury . Therefore, radiologists must be aware of the common clinical dyads seen in patients with multiple injuries Conclusion: By correlating the location of uptake with the find- to avoid delay in diagnosis and prevent avoidable morbidity and ings on the coregistered anatomic images the diagnostic accuracy mortality . of bone scans can be improved . SPECT-CT also enables the detection of tissue abnormalities which are not usually detected E383. Musculoskeletal Corticosteroid Injections: A Step-by- on nuclear scintigraphy . In cases of suspected osteomyelitis this Step Guide to Common and Innovative Applications for the technology can obviate the need for 24 hour delayed views in Practicing Radiologist patients with delayed blood pool clearance . Both sensitivity and Koo, J.1; Tumyan, L.2; Chakarun, C.2; White, E.2; Wolfson, N.2 1. specificity can be improved with the utilization of hybrid imaging . University of California, Los Angeles, Los Angeles, CA; 2. University of Southern California-Keck School of Medicine, Los Angeles, CA E382. Clinical Dyads: Traumatic Lesions that Commonly Address correspondence to L. Tumyan ([email protected]) Occur Together (CME Credit Available) Dunn, D.; Mansfield, L. Brooke Army Medical Center, San Antonio, Background Information: The purpose of the exhibit is to TX review the indications, key imaging findings, and the appropriate Address correspondence to L. Mansfield (liem_mansfield@hot- technique for common and novel applications of musculoskeletal mail.com) corticosteroid injections .

Background Information: In the United States, trauma is Educational Goals/Teaching Points: Corticosteroid injections the leading cause of death in persons under 40 years old and for arthritides affecting the knee and shoulder have remained third most common overall . Mortality and morbidity are due to some of the most common procedures for the practicing ortho- polytrauma, where multiple long bone fractures are seen in asso- pedist, rheumatologist, and general practitioner . More recently, ciation with vascular, visceral and soft tissue injuries, arising from novel imaging-guided techniques using fluoroscopy, ultrasound, a common mechanism of injury . and CT have been utilized for therapeutic injection in a variety of muscular and intra-articular locations . The exhibit will review the Educational Goals/Teaching Points: The purpose of this exhibit literature and discuss the indications, relative contraindications, is for the participant of this activity to understand the concept of plain film and MRI findings in patients referred for diagnostic and polytrauma; to be familiar of the common clinical dyads, trau- therapeutic joint injections . Our exhibit will provide step-by-step matic injuries that frequently occur together, and to understand instructions and common pitfalls for fluoroscopic-, CT- and ultra- the mechanism of injury accounting for the common clinical sound-guided musculoskeletal injections . This will include injec- dyads . tion of the flexor hallucis longus tendon sheath, as well as injec- tion of the pubic symphysis, hip, os trigonum, calcaneocuboid, Key Anatomic/Physiologic Issues and Imaging Findings/ talonavicular, tibiotalar, subtalar joints, sacroiliac, elbow, and Techniques: Examples of musculoskeletal-vascular dyads include shoulder joints . knee dislocation and popliteal artery injury, pelvic fracture and iliac artery laceration, skull fracture and epidural hematoma, Key Anatomic/Physiologic Issues and Imaging Findings/ scapulothoracic dissociation and axillary artery injury, posterior Techniques: Differentiating between the various inflammatory sternoclavicular dislocation and great vessels injury, and cervical and noninflammatory arthritides requires a combination of clini- spine fracture and vertebral artery dissection . Examples of frac- cal, imaging, and laboratory findings . Imaging evaluation should tures-visceral dyads include pelvic fracture and bladder or ure- begin with conventional radiography, but the radiologist must thral rupture, pelvic fracture and diaphragmatic rupture, lower also be familiar with normal and pathophysiologic features on ribs fracture and liver/spleen/kidney laceration, Chance fracture other imaging modalities such as CT and MRI . Innovative imag- and small bowel injury, rib fractures and pneumothorax, and frac- ing-guided techniques have led to successful injection of the flex-

304 El e c t r o n i c Ex h i b i t s : Musculoskeletal or hallucis longus tendon sheath, as well as multiple joints E385. Imaging of the Musculoskeletal System in HIV (CME including the sacroiliac, pubic symphysis, elbow, talonavicular, Credit Available) calcaneocuboid, and subtalar joints . Allmendinger, A.; McLaughlin, V. St. Vincent’s Catholic Medical Center, New York, NY Conclusion: Corticosteroid injections of the musculoskeletal sys- Address correspondence to A. Allmendinger (amallmendinger@ tem involve minimally invasive procedures that play a significant gmail.com) therapeutic role . Our exhibit will review the indications, imaging findings, and provide a detailed guide with step-by-step instruc- Background Information: Musculoskeletal abnormalities are not tions of common and novel techniques for musculoskeletal injec- as common as pulmonary or central nervous system abnormalities tions . The viewer of the exhibit will be able to incorporate these in patients with HIV, however a wide spectrum of musculoskeletal techniques into their practice . abnormalities (soft tissue and bony) does occur . HIV disease decreases the body’s defense mechanisms, predisposing the body to common and opportunistic infections, anemia and HIV-related E384. Phase Sensitive Fat-Water Separation for malignancies . Additionally, avascular necrosis may occur secondary Musculoskeletal Imaging: Core Concepts and Methodologies to HIV therapy . Musculoskeletal involvement generally is more Yao, L.; Gai, N. National Institutes of Health, Bethesda, MD common in the later stages of HIV infection, although arthritis can Address correspondence to L. Yao ([email protected]) occur at any stage . Our purpose is to provide a case-based, picto- rial essay of musculoskeletal pathology in HIV disease . Background Information: Radiologists commonly employ spec- tral fat suppression when performing MRI of the body and musc- Educational Goals/Teaching Points: The goals are to review uloskeletal system . The fundamentals and methods of phase sen- the common MR sequences utilized in imaging musculoskeletal sitive fat water separation are less familiar to radiologists and pathology in HIV; discuss the common and opportunistic infec- practitioners . Phase sensitive fat water separation is potentially tions as well as HIV-related malignancies; discuss the various more robust than spectral fat suppression, and confers advantag- manifestations of avascular necrosis related to HIV therapy, and es for quantitative imaging approaches, but requires processing discuss bone marrow signal abnormalities commonly found in of acquired images . Potential clinical applications for image HIV patients . quantitation include assessment of muscle atrophy, bone marrow infiltration, and body composition . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: HIV infected patients may demonstrate a wide vari- Educational Goals/Teaching Points: This exhibit reviews funda- ety of musculoskeletal abnormalities not commonly encountered mental concepts underlying Dixon (Dixon WT . Radiology 1984) in every day practice . This exhibit is a case-based, pictorial essay fat-water separation methodology . Potentially confusing core con- discussing HIV disease and manifestations demonstrated on MR cepts are highlighted and explained . The exhibit emphasizes imaging . Soft tissue and bony pathology will be presented with a newer phase correction strategies . Methods and principles of fat focus on common and opportunistic infections, bone marrow water separation are illustrated in clinical thigh muscle MR stud- pathology and HIV-related malignancies . ies to make the concepts visually accessible and more intuitive to radiologists . Conclusion: Although musculoskeletal manifestations are not as common as pulmonary or central nervous system abnormalities, Key Anatomic/Physiologic Issues and Imaging Findings/ recognition of these conditions is important for early and appro- Techniques: The exhibit discusses and illustrates these concepts priate initiation of therapy . After completing this exhibit, the view- and methods: complex image data, image phase, and phase er will be confident identifying infectious, neoplastic and bone arithmetic; image acquisition considerations for Dixon-based marrow pathology commonly encountered in the HIV patient . spectroscopic imaging; determinants and ranges of phase ambi- guity; two point vs . three point Dixon methods; phase correction (Ma J. Magn Reson Med 2004) vs . phase unwrapping; region E386. Malignant “Triton” Tumor: An Imaging Perspective growing strategies and enhancements (Schmidt MA, Fraser KM . J Sunnapwar, A.1; Lemos, J.2; Lemos, D.2; Choudhary, S.1; Magn Reson Imaging 2008) . Restrepo, C.1 1. University of Texas Health Science Center at San Antonio, San Antonio, TX; 2. University of Vermont, Burlington, VT Conclusion: Newer region growing phase correction strategies Address correspondence to A. Sunnapwar ([email protected]) are robust, efficient, and easy to implement . These approaches may raise the practical utility of Dixon fat water separation meth- Background Information: Malignant Triton tumor is a rare odologies . Associated scan techniques are time efficient, particu- malignant peripheral nerve sheath tumor with rhabdomyosarco- larly on current, high gradient performance scanners . Phase sen- matous differentiation . It is a type of aggressive sarcoma consist- sitive methods may improve fat suppression in clinical imaging ing of both malignant schwannoma cells and malignant rhab- and could be particularly helpful for contrast-enhanced studies . domyoblasts . We present imaging features of five cases of this The same strategies may also facilitate quantitative clinical MRI rare tumor with systematic review of the literature . measurements of fat fraction . Educational Goals/Teaching Points: The goals are to describe the histopathology of malignant Triton tumor (MTT); give an overview of the demographics and clinical presentation of MTT; present imaging features of five cases of MTT that were proven by histopathology, and to briefly review management and prog- nostic issues of MTT .

305 El e c t r o n i c Ex h i b i t s : Musculoskeletal

Key Anatomic/Physiologic Issues and Imaging Findings/ E388. MR Safety and Compatibility of Silver-Based Wound Techniques: Over a period of seven years five cases of his- Dressings at 7T topathologically proven MTT were observed . Three patients had Sammet, S.; Chaudhry, Z.; Coffey, R.; Crockett, A.; Miller, S.; Yuh, imaging with CT scans and two patients had MRI . Each patient W.; Knopp, M. The Ohio State University, Columbus, OH had tumor in different locations . A systematic search of the litera- Address correspondence to S. Sammet ([email protected]) ture was made . Objective: Silver containing products are an integral part of topi- Conclusion: Malignant tumors arising from peripheral nerve cal wound care for burn patients . Silver-based burn wound dress- sheath or in neurofibromas may contain other mesenchymal ele- ings are applied to the wound and left in place until the wound ments such as rhabdomyosarcoma . These tumors are also com- is closed . Package inserts for silver-based burn wound dress- monly referred in pathology literature as “Triton” tumor . These ings recommend their removal prior to any MRI procedures . tumors can arise anywhere in the body from the neck region to Repeated dressing removal is associated with a disruption of the the foot . Because of aggressive behavior they have a worse prog- wound bed which may delay wound healing, increased patient nosis than classic malignant peripheral nerve sheath tumors . A pain, analgesia use, anxiety, and stress . The purpose of this study preoperative diagnosis is important as more radical surgery and was to determine whether silver-based wound dressings are aggressive management is necessary . compatible with MRI imaging by investigating if ultra high field MRI and silver-based dressings produce either increased body surface temperature and/or caused distortions in the resulting E387. Imaging Features of Recurrent Giant Cell Tumors: MR image . Review of Radiographic, Ultrasound, CT, and MRI Findings Aagesen, M.; Jacobson, J.; Girish, G.; Morag, Y.; Kalume Brigido, Materials and Methods: On three limbs of euthanized pigs, M.; Sabb, B. University of Michigan, Ann Arbor, MI wounds were created in the porcine skin with a scalpel . The Address correspondence to M. Aagesen ([email protected]) depth of the wound varied from superficial skin wound to the surface of the fascia of the muscle . Three standard silver contain- Background Information: Giant cell tumor is a relatively com- ing burn wound dressings were placed in a dry application on mon tumor of the osseous structures, comprising 18-23% of all the wounds . Four fiber optic temperature probes were placed in benign skeletal neoplasms . Orthopedic surgeons will commonly four different locations [(A) on the superficial skin wound, (B) on treat giant cell tumors with a combination of curettage, bone the deep fascial wound and two under the wound dressing: (C) grafting, and cement placement . Radiologists should be familiar in an area with a superficial skin wound and (D) in an area with with the common postoperative appearance after giant cell a deep fascial wound) . The limbs were scanned in a 7T whole tumor resection . The recurrence rate for giant cell tumors after body MR scanner (Philips Healthcare, Cleveland, OH) using placement of graft and cement is 2-25%, therefore familiarity standard MRI sequences . The temperature in the four locations with the imaging appearance of recurrent giant cell tumors on was recorded every 20 seconds . All MR images were graded multiple different modalities is essential for the general and mus- independently for distortion . culoskeletal radiologist . Results: All three examined silver containing wound dressings Educational Goals/Teaching Points: This exhibit will detail the didn’t increase the surface temperature of porcine skin wounds appearance of giant cell tumors; the postoperative appearance of significantly when the rf-sequences of Table 1 were used to scan treated giant cell tumors, (including bone graft and cement), and the pig limbs at 7T . The maximum temperature increase of 0 .2°C, the findings of recurrence giant cell tumors in the surgical field for areas covered with the wound dressings, was similar to areas and adjacent soft tissues . without wound dressings, and was within the measurement accuracy of fiber optics thermometer . The dry and wet application Key Anatomic/Physiologic Issues and Imaging Findings/ of the silver containing wound dressings at 7T showed no tem- Techniques: We queried our RIS database and electronic medi- perature differences during the MRI exam . Image distortions in cal records to identify patients who had undergone surgery for all images were graded as minimal by two independent readers . giant cell tumors and had follow-up imaging at our institution . We identified 77 patients who had undergone surgery for patho- Conclusion: The maximum measured temperature increases of logically proven giant cell tumors . Out of these patients, 13 sub- the skin with silver containing wound dressings are within the jects had biopsy proven recurrences, and three had biopsy prov- allowed temperature-rise guidelines of The and Drug en second recurrences . We reviewed the imaging findings of Administration (FDA) . Based on these results, all tested wound giant cell tumor recurrences on radiographs, ultrasound, CT, and dressings are both safe and compatible with MRI at 7T . MRI for these patients and characterized the most common loca- tions, appearances, signal characteristics, and presence or absence of involvement of cement/bone graft . E389. Orthopedic Implants and Complications: What the Radiologist Must Know (CME Credit Available) Conclusion: This presentation will provide the reviewer with the Arnold, G.; Yadavalli, S.; Werder, G. William Beaumont Hospital, most common imaging findings of recurrent giant cell tumors Bloomfield Hills, MI after surgical treatment and resection of the primary lesion with Address correspondence to S. Yadavalli ([email protected]) bone graft or cement placement . The radiographic, ultrasound, CT, and MRI features of giant cell tumor recurrence will be dis- Background Information: With an aging demographic and cussed and illustrated . advances in orthopedic surgery, newer prostheses and implants are being used daily . In the past radiographs were the mainstay

306 El e c t r o n i c Ex h i b i t s : Musculoskeletal of postoperative follow-up . However, with advances in CT and Educational Goals/Teaching Points: The goals are to review MRI techniques, cross-sectional imaging has become an impor- indications for performing CT in trauma patients who have tant part of the diagnostic tools for orthopedic hardware follow- undergone surgical fixation or joint replacement; examine techni- up . The radiologist plays an important role, not only in accurate cal aspects and benefits of generating 3D CT images in postoper- interpretation of the postoperative studies, but also in the devel- ative patients, and demonstrate postoperative skeletal complica- opment, optimization and protocoling of imaging exams for the tions with 3D CT imaging . evaluation of the hardware, the osseous structures and the sur- rounding soft tissues . Familiarity with the commonly used ortho- Key Anatomic/Physiologic Issues and Imaging Findings/ pedic procedures, devices and possible complications is essential Techniques: The exhibit will be organized as follows: a) indica- for the radiologist . tions for CT imaging of the postoperative trauma patient; b) tech- nique (acquisition of CT imaging isotropic datasets, construction Educational Goals/Teaching Points: The goals are to review of 3D CT images); c) advantages of 3D CT imaging in the postop- the normal appearance of commonly used prostheses and ortho- erative setting; d) expected postoperative appearance; e) postop- pedic fixation hardware, including alignment and positioning; erative complications (hardware failure, particle disease [osteoly- familiarize the viewer with possible complications related to the sis], nonunion, new fracture, infection, heterotopic ossification) . hardware and in the surrounding osseous structures and soft tis- sues, and illustrate with multiple examples how various imaging Conclusion: 3D CT imaging plays an important role in diagnos- modalities can be used to optimize assessment of orthopedic ing abnormalities of the postoperative skeleton . The creation of hardware and the associated musculoskeletal structures . 3D CT images minimizes artifacts related to the presence of metal in the postoperative patient and the demonstration of Key Anatomic/Physiologic Issues and Imaging Findings/ postoperative complications with 3D CT imaging is often superior Techniques: The exhibit will have a case-based-learning type of to that of traditional axial CT imaging alone . format . Various diagnostic modalities including radiographs, CT, MRI, nuclear scintigraphy, ultrasound and arthrography will be used to present cases that illustrate many of the complications E391. Epidermolysis Bullosa: Imaging Manifestations of a seen with orthopedic hardware placement . Complications related Rare Disorder (CME Credit Available) to the prostheses or fixation hardware and cement, including Knox, M.; Beddy, P.; Dunne, R.; Meaney, J.; Wilson, G. St. James’s abnormal positioning, fracture, polyethylene wear, dislocation Hospital, Dublin, Ireland and loosening will be discussed . Abnormalities due to infection, Address correspondence to M. William ([email protected]) particle disease, heterotopic ossification, tendon failure and mus- cle atrophy will also be described . Background Information: Epidermolysis bullosa (EB) is a group of inherited bullous disorders characterized by blister formation Conclusion: Awareness of normal and abnormal appearances of in response to mechanical trauma . It has a wide spectrum of various types of joint replacements and fixation devices being presentations from the relatively minor simplex form through to used with advances in surgical techniques enables the radiologist the severe recessive dystrophic type . to play an essential role in the care of the postoperative patient . The well-informed radiologist is able to optimize the most appro- Educational Goals/Teaching Points: The aim of this exhibit is priate exam to evaluate the problem and accurately interpret any to illustrate the array of imaging findings and highlight the prob- complications that may be present . lems faced with interventional procedures in patients with EB .

Key Anatomic/Physiologic Issues and Imaging Findings/ E390. CT of the Postoperative Trauma Patient: Added Value Techniques: We have performed a retrospective review of over of 3D CT Imaging in Defining Skeletal Complications 40 cases of EB . Cases include multilevel esophageal strictures, Fayad, L.; Patra, A.; Fishman, E. Johns Hopkins University, feet and hand contractures with associated characteristic skeletal Baltimore, MD abnormalities and squamous cell cancer formation in areas of Address correspondence to L. Fayad ([email protected]) repetitive trauma . We also present three cases of the rare ‘inverse’ form of EB . We describe the interventional radiology Background Information: Effective imaging methods are neces- procedures performed on some of our patient cohort, including sary when evaluating the postoperative trauma patient with peripheral access and feeding tube placement, and the challeng- metal hardware . Although radiographs are utilized frequently, es faced in this particular group of patients . they generally provide an inadequate postoperative assessment, as they cannot evaluate bones and joints in three dimensions . Conclusion: Radiology has an important role in the multidiscipli- Cross-sectional imaging with MR imaging is often not effective in nary management of patients with EB, from diagnosis of the mul- the postoperative setting, since ferromagnetic metals distort mag- tiple manifestations to the treatment of specific complications . netic fields and result in severe artifact on MR images . Hence, CT has emerged as an important tool for the postoperative evalua- tion of the skeleton . In recent years, advances in CT technology and optimization of protocols have resulted in high quality post- operative 3D CT images that enable the identification of patholo- gy, despite the presence of metal .

307 El e c t r o n i c Ex h i b i t s : Musculoskeletal

E392. Accessory Ossicles and Sesamoid Bones from Head to ture fixation . The purpose of this exhibit is to review the radio- Toe: Innocent Bystanders or Mischievous Neighbors? (CME graphic findings of these complications including, among others, Credit Available) hardware misplacement, postoperative infection, hardware loos- Mazzie, J.1; Smith, S.2; Ramas, C.1; Math, K.3; Katz, D.1; Luchs, ening, and failure of fracture union . J.1 1. Winthrop-University Hospital, Mineola, NY; 2. University of Maryland, Baltimore, MD; 3. Beth Israel Medical Center, New Key Anatomic/Physiologic Issues and Imaging Findings/ York, NY Techniques: A review of general types of orthopedic appliances Address correspondence to D. Katz ([email protected]) used for fracture fixation will be provided . Important technical considerations including imaging the entire length of the hard- Background Information: Accessory ossicles and sesamoid ware and comparing to prior films will be discussed . Multiple bones are routinely encountered and may be the source of a examples of hardware complications will be shown to illustrate patient’s pain . The purpose of this exhibit is to remind radiolo- the variety of problems that can be diagnosed radiographically . In gists that these bones are not always as innocent as they appear, some cases, the method of treating the complication will also be and to help them decipher amongst fractures, dislocations, for- included . eign bodies, and such ossicles/sesamoids . Conclusion: Internal fracture fixation devices are commonly eval- Educational Goals/Teaching Points: The common and uncom- uated radiographically and it is important to be able to recognize mon accessory ossicles and sesamoid bones of the body will be complications associated with the hardware . This review will reviewed in an organized fashion from head to toe by anatomic illustrate a variety of problems that can be encountered . region, with possible associated complications related to their presence if applicable . Examples will be shown of the os acetab- uli- and os acromiale-related impingement syndromes, as well as E394. The Nuts and Bolts of Fracture Management os styloideum and os trigonum syndromes . Additionally, compli- Carr, R.; Mulcahy, H.; Chew, F. University of Washington, Seattle, cations of the accessory navicular bone will be presented . WA Fractures and osteonecrosis will be shown . Address correspondence to F. Chew ([email protected])

Key Anatomic/Physiologic Issues and Imaging Findings/ Background Information: Advances in fracture management Techniques: Multimodality imaging will be used to demonstrate have resulted in an ever-increasing array of surgical innovations . the relevant findings of symptomatic and problematic accessory Recognizing the normal and abnormal appearances of special- ossicles and sesamoid bones and their mimics, including plain ized hardware and other implants presents a continuing chal- films, CT, MR, and bone scan . The differential diagnosis will be lenge for the radiologist . reviewed, as well as the relevant imaging and clinical literature . Educational Goals/Teaching Points: Following the completion Conclusion: Inevitably, while interpreting imaging studies on a of this educational activity participants should be able to recog- given day, general and musculoskeletal radiologists will encoun- nize the normal appearance of fracture treatment devices; ter accessory ossicles and sesamoid bones . These ossicles are not explain and discuss their indications and mechanisms of action, without consequence, and can often contribute to patient symp- and identify treatment-related complications of fracture healing . toms of pain and discomfort . This exhibit will remind the radiolo- gist that these bones are not always as innocent as they appear, Key Anatomic/Physiologic Issues and Imaging Findings/ and that imaging is critical in the differentiation of incidental ossi- Techniques: It is important to understand the function and nor- cles and sesamoid bones from clinically relevant ones . mal appearance of these devices so that complications can be detected . Presurgical, intraoperative, and postsurgical images are provided with biomechanical and physiological correlations, as E393. Complications of Orthopedic Fixation Hardware—A well as examples of complications . Pictorial Review (CME Credit Available) Katzen, J.; Brindle, K.; George Washington University, Bethesda, MD Conclusion: As techniques for fracture management evolve, the Address correspondence to K. Brindle ([email protected]) radiologist must keep pace with these advancements . By under- standing the indications, functions, and potential complications Background Information: The goal of fracture fixation is to pro- of these newer devices, the radiologist will be able to provide vide stability in addition to restoring anatomic alignment and optimal imaging care for patients undergoing fracture treatment . function . This can be accomplished by internal or external meth- ods . Internal fixation implies the use of some type of hardware, whether it is pins, wires, plates and screws, or intramedullary E395. Name the Mechanism: Pattern Recognition of rods or nails to maintain the reduction . After the initial reduction, Musculoskeletal Injuries (CME Credit Available) follow-up imaging is performed in order to assess for healing Smith, S.1; Mazzie, J.2; Luchs, J.2; Lazzara, B.2; Scalcione, L.2; and to evaluate for complications . It is important to recognize Math, K.3; Katz, D.2 1. University of Maryland, Baltimore, MD; 2. complications early because failure to do so can result in devas- Winthrop-University Hospital, Mineola, NY; 3. Beth Israel Medical tating consequences for the patient . Center, New York, NY Address correspondence to D. Katz ([email protected]) Educational Goals/Teaching Points: Radiographs play an important role in the assessment of orthopedic fixation hardware Background Information: There is a long list of named or un- and the potential complications associated with it . Most often, it named fractures and/or dislocations on imaging studies, all of is the only imaging modality used to evaluate patients with frac- which are associated with specific mechanisms of injury . The pur-

308 El e c t r o n i c Ex h i b i t s : Neuroradiology pose of this exhibit is to present diverse examples of multiple will also be provided . US studies are obtained without additional fractures on plain radiographs and CT as well as bone contusion charge to the patient whose MRI studies were interpreted as patterns on MRI, from several centers which routinely image positive by radiologists at our institution specializing in MSK trauma patients . imaging, and subsequently confirmed by orthopedic evaluation .

Educational Goals/Teaching Points: Using an interactive pro- Conclusion: A Web-based US anatomy atlas will provide a useful gram, the exhibit will not only test but also reinforce the different and quick online reference of MSK pathology diagnosed with US mechanisms which are responsible for each injury . This will be for both radiologists and nonradiologists . The atlas will hopefully organized according to anatomic structures in order to enhance foster a better understanding and increased utility of US in con- learning and review of the material . Mechanisms of injuries and junction with MRI when diagnosing MSK pathology . their associated types of fracture/dislocations that will be reviewed include many different anatomic regions, such as the cervical spine, pelvis, wrist, and forearm . The treatment options will be briefly reviewed . Ne u r o r a d i o l o g y /He a d a n d Ne c k

Key Anatomic/Physiologic Issues and Imaging Findings/ E397. A Hardware Store for the Brain – An Introduction to Techniques: The roles of plain films as well as of CT and MR for Advanced Intracranial Monitoring and Therapeutic Devices the recognition of patterns of musculoskeletal injuries will be on Current Neuroimaging emphasized . Tsappidi, S.; Narayanan, S.; Mullins, M. Emory University, Decatur, GA Conclusion: There is a long list of named as well as un-named Address correspondence to S. Tsappidi ([email protected]) fractures and/or dislocations on imaging studies, all of which are associated with specific mechanisms of injury . The clinical severi- Background Information: Advances in neurocritical care, neuro- ty of the injuries, the causative mechanisms, and the specific sig- surgical and neuroendovascular therapy have led to a new era in nificant urgent radiographic findings which should be made, all understanding and managing brain injury . Modern intracranial need to be considered by the radiologist interpreting trauma monitoring devices (tools) provide previously unprecedented imaging studies . The role of CT and MR in the trauma setting also monitoring strategies . Neurosurgical and endovascular hardware needs to be considered . has trended toward newer, lighter and smaller materials . We present a summary of many such advanced devices currently in use, with corollary descriptions and neuroimaging features . E396. Web-Based Musculoskeletal Ultrasound Anatomy Atlas Educational Goals/Teaching Points: A pictorial essay demon- Kovalenko, B.; Karol, I.; Cohen, S. Bridgeport Hospital-Yale strating common and uncommon intracranial surgical devices University, Bridgeport, CT supplanted by expected normal appearance on neuroimaging, Address correspondence to B. Kovalenko ([email protected]) intended function and a review with literature search on each device will be provided . Background Information: Ultrasound (US) is increasingly being recognized as an adjunctive modality to MRI in diagnosing musc- Key Anatomic/Physiologic Issues and Imaging Findings/ uloskeletal (MSK) pathologies . However, understanding US anat- Techniques: Until the last decade, most monitoring intracranial omy and recognizing pathognomonic signs on US images can be hardware included the intraparenchymal Camino bolt to measure a challenging task, particularly for nonradiologists . A Web-based intracranial pressure (ICP) and the external ventricular drainage MSK US anatomy atlas, which presents normal and abnormal (EVD) catheter to drain cerebrospinal fluid . Better understanding anatomy in an interactive user friendly interface would be invalu- of brain injury pathophysiology has led to newer devices with able for correlating clinical findings . multimodality monitoring capability . Measurement of cerebral blood flow (CBF) and ICP with qualitative laser Doppler and Educational Goals/Teaching Points: Physicians, physicians-in- quantitative thermal diffusion flowmetry is still considered experi- training and medical students, will have a Web-based resource mental but active in current practice . Brain tissue oxygenation that is quickly accessible online . The Web-based atlas will contain (pBtO2), coupled with intracranial temperature (ICT) and ICP is a series of images of normal and abnormal findings, commonplace in many centers . Cerebral microdialysis (CMD) is which are navigated in a scrollable fashion, with enabled mouse another monitoring system involving a tiny intraparenchymal and cursor label cross referencing . Cross referencing of images probe for injecting and collecting dialysate towards multiple neu- between different imaging planes will allow for better correlation rochemical marker analysis . Continuous EEG (electroencephalog- and understanding of US findings . Embedded Web links will also raphy) monitoring (cEEG) typically utilizes MRI compatible leads direct users to electronic online literature and references . placed on the scalp and sometimes in the subdural space . Endovascular liquid embolizing radio-opaque agents, platinum- Key Anatomic/Physiologic Issues and Imaging Findings/ based coils, nitinol-based intracranial stents, combination intrac- Techniques: The Web-based atlas will concentrate on typical US ranial monitoring devices, programmable ventriculoperitoneal imaging findings with respect to tendonopathy particularly within shunts, deep brain stimulator (DBS) electrodes, among other the rotator cuff and Achilles tendon . Ligamentous, joint, muscle newer advances, will also be reviewed . and nerve anatomy and pathology will also be demonstrated . Dynamic scanning and extended field of view images will be pre- Conclusion: A review of intracranial “tools” and their imaging sented where applicable . Interactive scrollable series of arthro- characteristics is provided, likely helpful for neuroimagers to pro- gram images with labeled anatomy of common MSK pathologies vide the most reliable interpretations towards quality patient care .

309 El e c t r o n i c Ex h i b i t s : Neuroradiology

E398. Complicated Migration of Ventriculoperitoneal Shunt after administration of contrast agent . In addition, the risk factors Catheter into the Heart With its Successful Retrieval by an for contrast induced nephropathy (CIN) were recorded .We also Interventional Procedure Using the Transfemoral Approach assessed the amount of contrast injected . CIN was defined as an Park, D.; Jung, W.; Ryu, J.; Heo, J.; Kim, Y.; Park, C.; Hahm, C. increase of the serum creatinine-level of > 25% above baseline Hanyang University Guri Hospital, Guri, South Korea Address cor- within 48 hours after contrast agent administration . respondence to D. Park ([email protected]) Results: The male:female ratio was 3:2, with age ranging from Objective: A ventriculoperitoneal (VP) shunt is the most com- 10 years to 88 years . The mean amount of contrast injected for mon treatment for hydrocephalus . Cervicothoracic complications CTA was 80 cc (Iohexol 350) and for angiography/embolization it with VP shunts are rare, but we present extremely rare case of ranged from 60 cc to 200 cc (Iohexol 300) with mean of 110 cc . the distal migration of distal catheter of a VP shunt into the All had normal initial values . Compared to their initial values, the heart, via the internal jugular vein, which is successfully retrieved serum creatinine after the two procedures did not increase signif- by an interventional procedure using a transfemoral approach . icantly in any of the patients . Mean serum creatinine value before CTA was 0 .68 with standard deviation of 0 27. and mean on sec- Materials and Methods: A 68-year-old woman, who underwent ond day after catheter angiography/embolization was 0 .27 with the placement of right frontal VP shunt due to hydrocephalus standard deviation of 0 27. . that developed after aneurysmal clipping, presented with mental declination . Conclusion: Even though CT angiography shortly followed by catheter angiography represents a high contrast load to the kid- Results: Serial plain chest X-rays and CT revealed the distal cath- neys, this appears to have no adverse affect on renal function . eter to be gradually pulled into the internal jugular vein, and finally into the right ventricle of the heart . A right lower neck inci- sion was performed to access the distal catheter, which was then E400. A Simplified Algorithmic Approach to the Posterior slowly pulled up out of the heart, but failed to pass through the Fossa: A Compendium of the Commonplace, the Curious and superior vena cava because the large size of the distal catheter the Confounding (CME Credit Available) knotted . After cutting the catheter at lower neck level, it was Ferretti, J.; Grossman, J.; Velayudhan, V.; Lev, S. Nassau University ensnared and pulled out through the femoral vein by an inter- Medical Center, Copiague, NY ventional procedure . Address correspondence to V. Velayudhan ([email protected])

Conclusion: The migration of the distal catheter of a VP shunt Background Information: We provide a framework to analyze probably occurred with the perforation of the internal jugular the complex anatomy and pathology of the posterior fossa, vein near the distal catheter tract . Slow venous flow and negative which may present in the emergent setting . inspiratory pressure may have gradually pulled the catheter up into the right atria and ventricle of the heart . It can be extracted Educational Goals/Teaching Points: The goals are to present safely in the interventional procedure with transfemoral venous a location-based approach to posterior fossa lesions and review approach . the characteristics of radiological mimics . The participant in this educational activity will learn how assessment of the fourth ven- tricle can pinpoint the abnormality . E399. Effect on Renal Function from High Contrast Load in Subarachnoid Hemorrhage Patients Having Both CT Key Anatomic/Physiologic Issues and Imaging Findings/ Angiography and Catheter Cerebral Angiography Within 24 Techniques: Analysis of a posterior fossa lesion should begin by Hours (CME Credit Available) noting whether it projects inwardly from the bordering dura or Sharma, A.; Wang, H. University of Rochester Medical Center, skull base or originates from the contents within . Dural lesions Strong Memorial Hospital, Rochester, NY may be tentorial (meningioma, metastases) or involve the Address correspondence to A. Sharma ([email protected]) venous sinuses (thrombosis) . Skull base lesions may be midline (clivus) or lateral (petrous apex) and can be destructive (chordo- Objective: At many institutions including ours, CT angiography ma, glomus tumors) or benign (fibrous dysplasia, cholesterol (CTA) has replaced catheter angiography as the initial evaluation granuloma) . Intraparenchymal pathology can be localized by not- of patients presenting with subarachnoid hemorrhage . However, ing the position of the fourth ventricle . Brainstem lesions (glio- catheter angiography is still obtained soon afterwards either for mas, central pontine myelinolysis) compress the fourth ventricle further evaluation or for embolization . In this study, we investi- posteriorly . Vermian lesions compress the fourth ventricle anteri- gate whether contrast induced nephropathy may develop from orly . Lesions of the cerebellar hemispheres, such as the “look- the high contrast load from the two procedures in the acute set- alikes” hemangioblastoma, juvenile pilocytic astrocytoma and ting . We hypothesis that there should be no significant compro- cystic metastases, deviate the ventricle laterally . An unusual mise of renal function from the additional contrast because cere- necrotic glioblastoma multiforme and atypical medulloblastoma bral catheter angiography does not expose the kidneys to large are also shown . The extra-parenchymal spaces can be subdivided bolus of contrast and is performed over a period of one to sever- into cisternal or intraventricular . Effacement of the quadrigeminal al hours . and ambient cisterns may indicate impending herniation . Prepontine cistern lesions are primarily midline (basilar tip aneu- Materials and Methods: We retrospectively studied 50 patients rysm, dermoid) . Cerebellopontine angle lesions (epidermoids, who presented with subarachnoid hemorrhage and underwent meningiomas and schwannomas) are at the anterolateral poste- CT angiography and catheter angiography/embolization within rior fossa . A trigeminal schwannoma and a cystic vestibular 24 hours . We assessed creatinine, before and at least two days schwannoma are demonstrated . Fourth ventricular lesions may

310 El e c t r o n i c Ex h i b i t s : Neuroradiology be solid (medulloblastoma, ependymoma) or cystic (echinococ- Princeton, NJ) . After the switch, some of the radiologists and MRI cus, neurocystercercosis) . Vascular lesions occur anywhere . technologists thought the postcontrast images more frequently Unusual lesions include a giant vein of Galen malformation, a showed patient motion artifact, possibly from patient discomfort posterior inferior cerebellar artery aneurysm presenting as a ven- related to contrast injection . In this study, we reviewed the MRI tricular bleed, superficial siderosis, and a dense basilar artery sign postcontrast images of patients just before we switched contrast (prelude to a massive pontine hemorrhage) . Venous thrombosis to those of patients after the switch to see if there was a statisti- may imitate subdural hemorrhage . Infectious/inflammatory proc- cal difference between the two contrast agents . esses are great mimickers . Meningitis can resemble a focal dural lesion . Rhomboencephalitis can mimic a brainstem glioma . Materials and Methods: We collected the data of 300 consecu- tive patients who underwent brain MRI consisting of 150 patients Conclusion: A systematic approach to the posterior fossa can receiving gadodiamide and the other 150 receiving gadoteridol . assist the radiologist in localizing and defining both common and Patients scanned under anesthesia or sedation, children below unusual entities, allowing for prompt and confident diagnosis . 10 years of age and patients with significant motion on the pre- contrast images were excluded . Only brain MR images were reviewed . The doses of the two contrast agents were the same, E401. Masses of the Posterior Cranial Fossa: Spectrum of being 0 .1–0 2. mmol/kg . The author who analyzed the MRI imag- Disease Among Children With Pathogic Correlation (CME es for motion was blinded to the type of contrast used . Credit Available) Devenney-Cakir, B. 1; Nadgir, H. 1; Castro-Aragon, I. 1; Delalle, I. Results: Of the patients meeting the criteria, there were 80 1; Golja, A. 2; Sakai, O. 1 1. Boston University Medical Center, patients in Group 1 who received gadodiamide and another 80 Boston, MA; 2. Children’s Hospital Boston, Boston, MA in Group 2 who received gadoteridol . No major adverse reaction Address correspondence to B. Devenney-Cakir (brooke.devenney- was reported in either group . Group 1 did not show any signifi- [email protected]) cant motion after contrast injection, whereas Group 2 showed motion in four patients . Because of the low incidence of motion, Background Information: The aim is to present the CT and MRI we used the Fisher exact test which gave a P value of 0 .12 indi- appearances and differential diagnosis of posterior cranial fossa cating no significant difference between the two groups . masses in the pediatric and young adult patient population with pathologic correlation . Conclusion: In reviewing our cases, we found the incidence of motion in those patients receiving gadoteridol was low but high- Educational Goals/Teaching Points: The exhibit will include an er than those receiving gadodiamide . However, this difference overview of anatomy of the posterior cranial fossa; a discussion was not statistically significant . of the differential diagnosis of posterior cranial fossa masses in the pediatric and young adult patient population; imaging pres- entation of a variety of posterior cranial fossa masses in children E403. Imaging Features of Neuromyelitis Optica and Review and young adults with discussion of typical and atypical features, of Recent Advances in Diagnosis and Treatment (CME Credit and direct correlation of imaging findings, pathologic specimen Available) and histopathologic features . Sidhu, G.; Glastonbury, C. University of California, San Francisco, San Francisco, CA Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to G. Sidhu ([email protected]) Techniques: This exhibit will present examples of the large spec- trum of benign and malignant neoplasms that occur in the poste- Background Information: Until recently, neuromyelitis optica rior cranial fossa, with emphasis on both classic and atypical (NMO), also known as Devic’s disease, was considered a variant imaging findings . Pathologic correlation will be included where of multiple sclerosis (MS) . With the discovery in 2004 of an appropriate . autoantibody relatively specific for NMO, however, there has been great progress in characterizing NMO as a unique disease Conclusion: The posterior cranial fossa is a common site for with different pathophysiology to MS, and different therapeutic intracranial neoplasms, including intra-axial, extra-axial, and implications . As such, early diagnosis of NMO has become osseous lesions . The differential diagnosis can be commonly nar- increasingly important, expediting confirmatory antibody testing rowed based on CT and MR imaging characteristics and patient and enabling earlier treatment . age demographics . Many imaging features of posterior cranial fossa masses can be correlated to histopathologic findings . Educational Goals/Teaching Points: The principal educational goal of this exhibit is to highlight the imaging findings of anti- body-positive NMO through a review of cases identified at our E402. Patient Motion on Brain MRI in Patients Receiving institution . Updates in the pathology, diagnosis, and treatment of Gadoteridol Compared to Those Receiving Gadodiamide NMO are also emphasized with comparison to other disease Sykes, J.; Malhotra, A.; Kumar, V.; Wang, H. University of Rochester states that have similar presentations, such as optic neuritis and Medical Center, Rochester, NY transverse myelitis . In addition we describe distinguishing fea- Address correspondence to H. Wang ([email protected] tures of NMO as characterized by newer advanced imaging tech- ter.edu) niques such as diffusion tensor imaging (DTI) .

Objective: Due to recent concern of nephrogenic systemic fibro- Key Anatomic/Physiologic Issues and Imaging Findings/ sis, our MRI center made a complete switch from gadodiamide Techniques: For decades NMO was considered an aggressive var- (GE Healthcare, Princeton, NJ) to gadoteridol (Bracco Diagnostics, iant of MS, relatively resistant to treatment and offering a dismal

311 El e c t r o n i c Ex h i b i t s : Neuroradiology prognosis . In 2004 a specific IgG autoantibody targeting a water- E405. Susceptibility Imaging and conducting membrane channel (Aquaporin 4) at the blood-brain- Small, J.1; Haacke, E.2; Schaefer, P.1 1. Massachusetts General barrier was found . This has been shown to be quite specific for Hospital, Boston, MA; 2. Wayne State University, Detroit, MI NMO and is not typically present in MS patients . Many other Address correspondence to J. Small ([email protected]) distinctions have been identified since that discovery which led to a revision of the clinical diagnostic criteria of NMO in 2006 . Background Information: Susceptibility refers to the property or Concomitant optic pathway and cervical cord involvement tendency of a substance to get magnetized when exposed to a remains the cornerstone of radiologic diagnosis on NMO as dem- magnetic field . Magnetic resonance sequences that take advan- onstrated by the cases at our institution, though various limited tage of susceptibility effects to demonstrate pathology are pow- forms have now been identified . DTI offers the possibility of early erful and sensitive aids for diagnostic imaging . One of the key recognition and discrimination from MS, through assessment of applications of susceptibility sequences is the identification of the corpus callosum and otherwise-normal appearing brain tissue . hemorrhage and blood products, an essential component in the evaluation of hemorrhagic and ischemic stroke . Conclusion: The discovery of NMO IgG has permitted rapid advances in diagnosis and treatment of neuromyelitis optica . Educational Goals/Teaching Points: In the setting of hemor- Recognition of the imaging features of NMO including the classic rhagic stroke, susceptibility sequences can identify a pattern of optic pathway-cervical cord lesions as well as newly described hemorrhage that may indicate a specific stroke etiology . In the limited forms has therefore become increasingly important in the setting of acute ischemic stroke, these images can reveal hemor- care of these patients . rhagic transformation of infarcts and/or the presence of chronic microbleeds . They can also detect acute intra-arterial clot or intra- venous clot and they contribute to the improved safety and effi- E404. Neuroimaging of Pediatric Stroke (CME Credit cacy of MR-based selection criteria for thrombolytic therapy . Available) Importantly, they can also lend important information for the Acharya, D.; Holder, C. Emory University, Atlanta, GA exclusion of hemorrhage mimics such as hyperdense lesions on Address correspondence to D. Acharya (darshan.acharya@gmail. CT, cavernomas, or hemorrhagic and melanotic metastasis . com) Key Anatomic/Physiologic Issues and Imaging Findings/ Background Information: Stroke in children is uncommon, but Techniques: Although the term susceptibility-weighted imaging has potentially devastating morbidity and mortality . This exhibit (SWI) has been used in the past to refer to T2* gradient echo will guide the student through the imaging appearances of the (GRE) techniques, the more recent convention has been to intracranial complications of pediatric stroke, demonstrate the reserve this term for a distinct new sequence utilizing both mag- various imaging techniques involved, and discuss therapeutic nitude and phase information . Already, several clinical applica- options . tions of SWI for both adults and children have emerged including the improved delineation of cerebral venous microvasculature, Educational Goals/Teaching Points: The goals are to discuss hemorrhage detection, and depiction of low flow vascular malfor- the anatomy and pathophysiology of pediatric stroke; demon- mations as well as adding information to the evaluation of trau- strate characteristic imaging techniques for evaluating the disease ma, brain tumors, cavernous malformations and neurodegenera- process; show relevant imaging techniques, and demonstrate tive conditions . In the setting of acute stroke, SWI has been treatment options and their follow-up imaging appearance . shown to be much more sensitive that T2* GRE sequences in the detection of both acute and chronic intracranial hemorrhage . The Key Anatomic/Physiologic Issues and Imaging Findings/ added sensitivity and anatomic detail of SWI imaging may per- Techniques: The exhibit will include an overview of underlying haps be able to depict previously unseen lacunar infarctions . diseases and presentations, including cardiac, sickle cell, moya moya, vasculitis, dissection and thrombophilic states; an overview Conclusion: Susceptibility images are an essential component of of the role of and applications for , CT, CT the imaging armamentarium in the evaluation of hemorrhagic angiography, MRI, MR angiography, and angiography . The poten- and ischemic stroke . In addition, susceptibility sequences and tial role of other advanced imaging techniques will be discussed . susceptibility-weighted imaging techniques promise to improve our understanding, diagnosis and treatment of acute stroke . Conclusion: Stroke in the pediatric population is an uncommon but increasingly recognized problem . Various causative disease states are responsible, and several have characteristic imaging E406. Diffusion Tensor Imaging of Brainstem Disorders findings delineated above . Treatment options are available and (CME Credit Available) with improving understanding of the disease course and imaging Kessler, J.; Salamon, N. University of California, Los Angeles, Los findings, can be applied earlier, limiting associated morbidity . Angeles, CA Address correspondence to J. Kessler ([email protected])

Background Information: Diffusion tensor imaging (DTI) is a powerful technique that allows one to image white matter tracts in the brain . Although a great deal of work has evaluated the supratentorial brain, DTI tractography of the brainstem is a rela- tively new endeavor . Furthermore, little published research has utilized DTI to examine the anatomical changes seen in various diseases that affect the brainstem . The assessment of these ana-

312 El e c t r o n i c Ex h i b i t s : Neuroradiology tomical alterations may provide insight into new methods of stem or basal ganglia and sparing the parieto-occipital region, or both diagnosis and treatment . abnormal findings in anterior portions of the brain along with the parieto-occipital and cerebellum confirms that “P” standing for Educational Goals/Teaching Points: The goals are to provide the “posterior” in PRES makes it a misnomer . Hypertension is an overview of the anatomy of the brainstem as seen on DTI; absent in 25% of patients and, when present, does not typically provide an overview of various disorders that manifest as ana- reach the level of failed auto-regulation . tomical aberrations in the brainstem, and demonstrate DTI’s utili- ty in elucidating these brainstem abnormalities . Conclusion: Considering the popularity of the acronym PRES in both radiological and clinical circles, it seems to be reasonable to Key Anatomic/Physiologic Issues and Imaging Findings/ substitute “posterior” with “potentially” standing for “P” in the Techniques: Numerous disorders may affect the brainstem PRES acronym, as proposed by Narbone et al . This acronym mod- including tumors, congenital disease, degenerative diseases, and ification, altering its meaning but saving its appearance, may be Wallerian degeneration . The way in which these disorders affect justified since it emphasizes that reversibility is not spontaneous . normal white matter tracts can be better seen using DTI, as Elimination of the term posterior enables proper inclusion of opposed to standard MRI techniques . This exhibit will display cases in which parieto-occipital involvement is not prominent and normal white matter tracts of the brainstem including the pyram- avoids the use of the prefix “atypical” for such cases . It is likely idal tract, medial lemniscus, decussation of the superior cerebel- that expansion of our knowledge regarding this syndrome, will lar peduncles, middle cerebellar peduncles, inferior cerebellar result in a future redefinition or creation of a pseudoacronym . peduncles, and transverse pontine fibers . Additionally, it will dis- play how these tracts are either invaded, displaced or diminished in various pathological processes including glioma, cavernous E408. Diagnostic Performance of MR Perfusion and 18F-FDG malformation, multisystem atrophy, spinocerebellar atrophy, pro- PET in Differentiating Tumor Recurrence from Post- gressive supranuclear palsy, horizontal gaze palsy and scoliosis Treatment Necrosis (CME Credit Available) syndrome, Chiari malformation, and infarction . Mangla, R.; Ekholm, S.; Zhong, J. University of Rochester School of Medicine and Dentistry, Rochester, NY Conclusion: Diffusion tensor imaging is a powerful technique Address correspondence to R. Mangla ([email protected]) that may better demonstrate the integrity of the white matter fib- ers in the different disorders of the brainstem . Objective: Differentiation of tumor recurrence from treatment-re- lated necrosis may be difficult with conventional MR imaging when newly enhancing lesions appear . Our aim was to deter- E407. Misnomer of Posterior Reversible Encephalopathy mine the value of perfusion-sensitive dynamic susceptibility con- Syndrome—Not Only Posterior and Not Always Reversible trast MR imaging and 18F-FDG PET for differentiating recurrent Maizlin, Z.1; Shewchuk, J.2; Gandehari ,H.1; Kirby, J.1; Coblentz, neoplasm from non-neoplastic contrast-enhancing tissue . C.1; Maizels, L.1; Clement, J.3 1. McMaster University Medical Centre, Burlington, Canada; 2. Royal Columbian Hospital, New Materials and Methods: Thirty-six patients in whom new Westminster, Canada; 3. St. Paul’s Hospital, Vancouver, Canada enhancing lesions developed within irradiated regions were Address correspondence to Z. Maizlin ([email protected]) examined with perfusion-sensitive dynamic susceptibility contrast MR imaging . Nineteen of them also underwent 18F-FDG PET Background Information: In 2000 the term of posterior reversi- within a period of one to 25 days . Relative cerebral blood vol- ble encephalopathy syndrome (PRES) was suggested . Since then ume (rCBV) ratios and standardized uptake value (SUV) and the the acronym of PRES has become very popular in imaging and tumor-to-normal tissue (T/N) ratio were evaluated to determine clinical literature due to its shortness, easy to remember configu- whether the new enhancing lesions were recurrent or not . The ration, outlining the frequent localization of neuroimaging find- examinations limited due to artifacts were excluded from the ings along with the clinical and radiological outcome of this syn- study . The findings on perfusion findings were confirmed his- drome . Another possible reason for the popularity of the acro- topathologically in 20 patients and PET findings were confirmed nym PRES in clinical circles is the connotation of PRES with (ele- in seven patients . In other cases, tumor recurrence was distin- vated blood) PRESsure, since it is generally believed among clini- guished by lesions that progressively increased in size on serial cians that this diagnosis is specific for cases of hypertension . MR examinations over at least six months, and necrosis was dis- However, a few problems exist with the interpretation and com- tinguished by lesions that disappeared or decreased in size on mon understanding of PRES, questioning the legacy of “P” and serial MR studies over at least nine months . “R” in the acronym . Moreover, the entire mechanism responsible for the imaging appearance remains unclear and controversial . Results: The receiver operating characteristic curve analysis of each modality was performed . Sensitivity, specificity, positive pre- Educational Goals/Teaching Points: The goal is to analyze the dictive value (PPV), and negative predictive value (NPV) of controversial issues related to the acronym PRES . Cases of reversible dynamic susceptibility contrast imaging that was calculated to encephalopathy in predominantly anterior distribution of the find- diagnose recurrence were 83 .5%, 75%, 76 .1%, and 64 .4%, ings and PRES in patients without hypertension are demonstrated . respectively . Sensitivity, specificity, PPV, and NPV for determining recurrence on 18F-FDG PET were 78 .2%, 55%, 62 .1%, and 49 .2 Key Anatomic/Physiologic Issues and Imaging Findings/ %, respectively . Techniques: Although, reversibility is a frequent evolution of PRES when promptly treated, it is not a rule and some patients Conclusion: Perfusion-sensitive dynamic susceptibility contrast have an unfavorable outcome, in spite of prompt therapy . (DSC) MR imaging and 18F-FDG PET are clinically useful tools to Frequent frontal lobe involvement, cases of PRES affecting brain- differentiate the tumor recurrence from treatment related necro-

313 El e c t r o n i c Ex h i b i t s : Neuroradiology sis . The rCBV measurements on MR perfusion had better diag- approaches have been described in the literature such as manual nostic performance than the 18F-FDG PET . The major limitation tracing (Jernigan et al ,. 2001; Tisserand et al ,. 2002), semiauto- of perfusion imaging is susceptibility artifacts, in such cases 18F matic plane segmentation (Giedd et al., 1996; DeCarli et al ., -FDG PET may be more useful . 2005) and automatic atlas-based segmentation (Tisserand et al ., 2002) . Currently, universally accepted consensus for brain parti- tioning has not been established . Therefore, easily reproducible E409. Brainstem: Anatomy and Pathology (CME Credit standardized technique is anticipated . The purpose of this exhibit Available) is to describe a semiautomatic segmentation algorithm based on Kanekar, S.; Creutzburg, G.; Koconis, K.; Moshiri, S. Penn State dual-clustering and plane partitioning, that is highly automated, Milton S Hershey Medical Center, Hershey, PA reliable and reproducible; review various strategies for brain par- Address correspondence to S. Kanekar ([email protected]) titioning as described in the literature, and discuss the specific technological advantages and difficulties of each method . Background Information: CT has a major limitation in evalua- tion of posterior fossa pathologies . With MR, due to its high soft Materials and Methods: Segmentation was performed using a tissue differentiation capability, we are able to image in detail the high level programming environment . After image segmentation brainstem structures in detail and noninvasively . Several major of intracranial volume, sagittal plane was placed through the internal structures like substantia nigra, inferior olivary nuclei, red interhemispherical fissure . Coronal plane was placed through nuclei, cerebral peduncles, decussation of cerebellar peduncles, internal auditory canals . The posterior part was divided with the and medial lemnisci can be easily identified making radiologists axial plane, which was placed through the top of the cerebellum compelled to learn the detailed internal anatomy and their func- tentorium . Thus, the whole brain was divided semiautomatically tion . As diffusion tensor imaging (DTI) becomes more widely into six subsegments: right and left anterior cerebrum, posterior available it has become more important to understand the tract cerebrum and cerebellum . We also review previously reported anatomy and their function and direction on routine MR scans . methods, and discuss advantages and disadvantages of each method . Educational Goals/Teaching Points: The goals are to familiar- ize the viewer with normal anatomy of the brainstem and various Results: Segmentation with common landmarks and planes is tracts and cranial nerve nuclei it harbors (the knowledge of relatively easy, quick and reproducible however it has a limitation which is of vital importance as we move toward higher modali- that each region is not based on sulcal/gyral patterns . Voxel- ties like DTI), and illustrate various pathologies involving the based automatic segmentation software provides perfectly repro- brainstem and clinical signs and symptoms associated with it . ducible segmentation . It is also applicable to large datasets . According to the study by Allen et al (Neuroimage 2008), the Key Anatomic/Physiologic Issues and Imaging Findings/ quantitative effects of spatial transformation on regional brain Techniques: In this exhibit we illustrate the detailed anatomy of volume estimates are subtle . They also suggested that meta-anal- the brainstem on conventional MRI sequences which will help yses should take into account whether volumes are determined the radiologist in understanding the position of the vital struc- using spatially-transformed images and/or specific automated tures, tracts and location of various cranial nerve nuclei . We also methods . Manual tracing is still the most accurate method, present the spectrum of lesions involving the brainstem, which though it requires anatomical expertise, and it is highly labor are classified as: infection (meningitis, encephalitis, acute dis- intensive and time consumptive . seminated encephalomyelitis); trauma (axonal injury, Duret’s hemorrhages); tumors (primary like glioma, glioblastoma multi- Conclusion: We describe a semiautomatic segmentation method, forme, lymphoma and metastatic lesions); demyelinating condi- and review methods for partitioning brain . Various segmentation tions (multiple sclerosis, myelinolysis); vascular pathologies (cav- methods from manual to automatic are described and discussed ernoma, arteriovenous malformation and stroke); metabolic dis- in terms of advantages and disadvantages . Learning the various eases and degenerative diseases . strategies should contribute to reaching consensus for a standard brain partitioning method . Furthermore, it may contribute to trans- Conclusion: As DTI becomes more widely available it has lating quantitative imaging analyses to routine clinical practice . become more important to understand the normal anatomy of the brainstem, white matter tracts and their function on conven- tional routine MR scans . E411. MR Imaging Findings of a Large Meningioma in a Three-Year Old Child: A Case Report (CME Credit Available) Angileri, T.1; Verderame, F.1; Bartolotta, T.2; Taibbi, A.2; De Pietro, E410. Strategies for Partitioning the Human Brain in Three A.1; Banco, A.2 1. Villa Santa Teresa, Bagheria, Palermo, Italy; 2. Dimensions With a Review of Methodological Approaches University Hospital, Palermo, Italy Used for Quantitative Imaging Analysis (CME Credit Address correspondence to A. Taibbi ([email protected]) Available) Watanabe, M.; Saito, N.; Jara, H.; Sakai, O. Boston Medical Objective: The objective is to describe MR imaging findings of a Center, Boston, MA large atypical meningioma found in a 3-year-old child . Address correspondence to M. Watanabe ([email protected]) Materials and Methods: The pediatric patient with a clinical Objective: Neuroscientists divide the brain into anatomically history of epilepsy, lower limb tremble and psychomotor deficit, defined regions . Tomographic imaging modalities such as MRI underwent a 1 5. MR examination before and after intravenous and CT generate volumetric data sets . Consequently quantitative administration of 0 .2 mL/kg of gadoteric acid under sedation . imaging analysis requires defining volumetric partitions . Various The definitive diagnosis was obtained by means of histological

314 El e c t r o n i c Ex h i b i t s : Neuroradiology analysis of a resected specimen . The child was followed-up by CT DTI using SENSE mitigates susceptibility artifacts and can be used and/or MR examination after surgery . for neurosurgical planning .

Results: MR imaging showed a huge mass in the left frontal lobe, with unsure intra- or extra-axial origin, sized 10 .6 cm x 7 .4 E413. Diffusion Tensor Imaging as a Diagnostic Tool in cm . The tumor presented as solid in the upper part and cystic in Evaluating Brain Pathologies: Review Of Clinical Experience the lower . The mass – with solid part mainly isointense on With Over 170 Cases T1-weighted sequences, isohyperintense on T2-weighted Hochberg, A.; Booya, F.; Bhadilia, R.; Rojas, R. Beth Israel sequences and presenting a strong and inhomogeneous con- Deaconess Medical Center, Jamaica Plain, MA trast-enhancement–showed huge relationships with dura mater Address correspondence to F. Booya ([email protected]) and determined severe mass-effect with mid line shift, subfalcine herniation of left lateral ventriculus and hypertensive dilatation of Background Information: The white matter tracts cannot be the contralateral ventriculus . Histological examination character- individually identified by MRI or postmortem slices due to similar ized the mass as atypical meningioma WHO grade II . No evi- chemical composition . White matter tracts variable orientation dence of recurrence was observed at least up to the last MR fol- gives them different diffusion properties which is applied by dif- low-up performed six months after surgery . fusion tensor imaging (DTI) . DTI is the technique which measures diffusion in a series of different spatial directions in order to eval- Conclusion: Meningiomas, although common in adults, are rare uate white matter cytoarchitecture . We perform DTI routinely in in infancy and childhood . In our case surgical resection allowed a all brain MRI performed in one of our new MRI scanners . We strong and progressive improvement of neurological deficits . MR reviewed all the cases which were performed from June, 2008 to imaging is useful and mandatory for surgical planning and fol- September, 2008 . There were 179 cases which had DTI . Tumor low-up . (21), hemorrhage (15), infarction (27), demyelinating disease (12) and postoperative brain (10) had different manifestation on DTI with useful clinical interpretation . E412. Postoperative Fiber Assessment Using Diffusion Tensor Imaging in a Brain Tumor Patient at 7T (CME Credit Educational Goals/Teaching Points: DTI offers an overall view Available) of brain anatomy, including the degree of connectivity between Sammet, S.; Irfanoglu, O.; Koch, R.; Wassenaar, P.; Schmalbrock, different regions of the brain . We will demonstrate the usefulness P.; Yuh, W.; Knopp, M. The Ohio State University, Columbus, OH of daily clinical application of DTI in the evaluation of the com- Address correspondence to S. Sammet ([email protected]) mon brain pathologies .

Objective: Diffusion tensor imaging (DTI) measures molecular Key Anatomic/Physiologic Issues and Imaging Findings/ diffusion in the human brain to assess white matter fibers in vivo . Techniques: DTI is a helpful adjunct in daily practice . At low field strengths DTI with single excitation protocols faces Characterization of sensorimotor pathways or language center limited spatial resolution and low signal-to-noise ratio (SNR) . involvement by acute ischemic insults has strong correspondence These shortcomings can be effectively mitigated by the transition to clinical symptoms, prognosis and long-term management . DTI to high magnetic field strengths and by using parallel imaging improves tumor margin delineation, particularly in radiologically technology such as SENSitivity encoding (SENSE) . The purpose of ambiguous lesions such as T2 hyperintense peritumoral voxels . this study was to investigate the potential of 7T MRI to assess DTI provides anatomic guidance for preoperative planning and white matter fiber tracts in a patient after the resection of a brain demonstrates displacement and disruption of the white matter tumor for a follow-up surgery . tracts by tumor or hemorrhage .

Materials and Methods: DTI of the human brain of a 37-year Conclusion: Although the full potential of DTI will probably not old female patient after the resection of a brain tumor (oligoden- be realized until it is integrated with other modalities such as droglioma) was performed on a 7T whole body MR-scanner functional imaging, there are advantages of DTI in every day prac- (Philips Healthcare, Cleveland, OH) using a 16-channel SENSE tice such as determining prognosis, improving characterization of head coil (Nova Medical, Wilmington, MA) . Acquisition parame- white matter lesions and preoperative planning . ters: repetition time=3, 000 milliseconds; echo time=86 millisec- onds; field of view=230 mm2; matrix size=128 x 128; b=0, 1,000 seconds/mm2; slice thickness=2 mm; SENSE=4 and number of E414. Seizures! Neurocysticercosis: A Diagnostic Puzzle for signal averages=1 . To reduce motion artifacts in the DTI images the Emergency Physician and the Importance of Imaging the datasets were postprocessed and tracts representing nerve Bollepalli, S.; Yost, A.; Gridley, D.; Hedayati, P. Maricopa Medical fibers were reconstructed on the MRI scanner . Center, Gilbert, AZ Address correspondence to S. Bollepalli (srigayatri2000@yahoo. Results: SENSE-DTI at 7T allows acquisition of diffusion-weight- com) ed images with high signal-to-noise ratio and mitigates suscepti- bility artifacts successfully . Postoperative analysis of fractional ani- Background Information: Neurocysticercosis (NC) is the most sotropy (FA) maps and fiber tracts in a patient after resection of a common reported neuroparasitosis worldwide . Once an exotic brain tumor showed the course of the remaining fibers and disease in the US, NC has increased in reported incidence due to helped in planning a follow-up surgery . the impact of globalization and increased tourism . Maricopa Medical Center, serving a Latino rich population, has extensive Conclusion: Advanced MRI techniques such as diffusion tensor experience with polymorphic neurologic and neuropsychiatric imaging open new vistas in brain tumor research . Ultra high field manifestations of NC and the clinical course . Cysticercosis may

315 El e c t r o n i c Ex h i b i t s : Neuroradiology present as neurocysticercosis or extraneural cysticercosis, the ple of DWI sequence for the practicing radiologist . In the second former being a more common form . NC has a myriad of clinical half of the exhibit we show various pathologies which can show presentations, mostly as the convulsive form and less often as restricted diffusion and how DWI can be some times help in headaches, obstructive hydrocephalus, cysticercotic encephalitis, reaching the specific diagnosis . We categorize these pathologies ataxia, and dementia or very rarely as isolated optic nerve cyst- under following: hemorrhagic and non-hemorrhagic stroke, infec- icercosis . 80% of the affected patients are asymptomatic . NC rep- tion, trauma, hemorrhage, demyelination, and extra and intra-axi- resents the leading cause of adult onset seizures, constituting al neoplasm . The importance of DWI and its usefulness in differ- approximately 10 % of seizure cases seen in the emergency set- entiating and yet times giving specific diagnosis is highlighted . ting . Pathologic manifestations of NC include parenchymal forms which exist as cysts of varying stages, typically at the gray white Conclusion: This exhibit will be a core learning tool for DWI junction of brain parenchyma . Meningeal, intraventricular and sequence . spinal cysticercosis constitute the extra parenchymal forms . Its interesting characteristics enable an active cyst to remain viable in the human tissue for months to years . Imaging with CT or MR E416. Posterior Fossa Stroke: Vascular Syndromes and MRI plays a pivotal role in evaluating NC, as the diagnosis is virtually Correlation impossible based on clinical grounds . Serologic markers only Kanekar, S.; Thamburaj, K.; Popeliansky, E.; Creutzburg, G. Penn assist in confirmation of imaging findings when necessary . An State Milton S Hershey Medical Center, Hershey, PA early diagnosis at the time of initial presentation may avoid Address correspondence to S. Kanekar (sankan2000@yahoo. unwarranted tests, invasive biopsy, and patient anxiety . com)

Educational Goals/Teaching Points: The goals are to familiar- Background Information: The clinical picture of brainstem and ize the reader with the variable imaging presentation of NC; cor- cerebellar infarctions is variable and mainly depends on the area relate the imaging pattern with clinical sequelae, and inform the involved . The anatomy of the brainstem is complex due to the reader to consider NC as a differential in the relevant setting . presence of numerous tracts, vital structures and cranial nerve nuclei . Unlike supratentorial infarcts, a small stroke in the posteri- Conclusion: NC is emerging as a more common disease than or fossa can potentially be disastrous clinically . Infarction of the once thought in the US . Imaging plays an important role in diag- cerebellum and brainstem can produce characteristic clinical pat- nosis and treatment of the disease, particularly in cases with per- terns or syndromes . CT has a major limitation in the posterior plexing clinical presentations . fossa due to poor soft tissue differentiation and beam hardening artifact . MR, especially diffusion-weighted imaging (DWI) and thin high resolution T2-weighted imaging has revolutionized the diag- E415. Diffusion-Weighted Imaging: Physics and Its nosis of posterior fossa stroke . For best clinicocorrelation under- Applications in Nonstroke Brain Pathologies (CME Credit standing the anatomy of the posterior fossa structures and vascu- Available) lar pattern is important . Kanekar, S. Penn State Milton S Hershey Medical Center, Hershey, PA Educational Goals/Teaching Points: We illustrate the normal Address correspondence to S. Kanekar ([email protected]) vascular anatomy, anatomical variations, and territorial distribu- tion of the posterior fossa structures . We illustrate, with exam- Background Information: Diffusion-weighted imaging (DWI) ples, various brainstem vascular syndromes with clinical and MR provides viability information of the brain . The role of DWI in correlation . stroke has been well established due to its capability to diagnose stroke as early as 10-30 minutes . From its introduction in the mid Key Anatomic/Physiologic Issues and Imaging Findings/ 1990s, clinical application has been widespread . In the last few Techniques: We retrospectively reviewed MR images of 154 years, DWI has been found to be increasingly useful in diagnos- patients from our archive system with clinical and MR diagnosis ing or excluding the various nonstroke intra- and extra-axial of posterior fossa stroke . Axial T2, DWI/apparent diffusion coeffi- pathologies of the brain . Restricted diffusion, though once con- cient, fluid attenuated inversion recovery, gradient-echo, MR angi- sidered specific for stroke, can also be seen in various other ogram and perfusion images from these patients form the basis pathologies ranging from infection, neoplasms, trauma, and of this exhibit . We first illustrate in detail the normal vascular blood products to demyelinating condition . anatomy and territorial distribution of the various major and minor branches . We also review the vascular anatomical variation Educational Goals/Teaching Points: We simplify and make of the posterior fossa . We present the various brainstem vascular understandable the relevant physics and principles of DWI to the syndromes with clinical and imaging correlation, knowledge of practicing radiologist . DWI has an established role in imaging of which is very essential for the practicing radiologist . stroke . However there are various intracranial pathologies where this sequence can be extremely helpful in reaching the specific Conclusion: This exhibit will be a core learning module to diagnosis . We highlight this concept with illustrations . understand the normal vascular anatomy of the posterior fossa and various clinical syndromes associated with stroke . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: To understand application and usefulness of DWI sequence, knowledge of physics and principle behind this sequence is mandatory . We divide this exhibit into two parts . In the first half of this exhibit we simplify the physics and the princi-

316 El e c t r o n i c Ex h i b i t s : Neuroradiology

E417. Pearls and Pitfalls in Perfusion CT for Imaging of Educational Goals/Teaching Points: Our goals are to review Acute Ischemic Stroke (CME Credit Available) normal CN V anatomy; review common lesions, trauma, and Allmendinger, A.; Spektor, V. St. Vincent’s Catholic Medical Center, syndromes that affect all or part of its course, and demonstrate New York, NY how abnormalities along specific portions of the trigeminal nerve Address correspondence to A. Allmendinger (amallmendinger@ will lead to certain clinical manifestations . We will discuss these . gmail.com) This will improve patient assessment interactions with referring clinicians . Background Information: Perfusion CT is increasingly utilized as a diagnostic tool for evaluation of acute ischemic stroke . Key Anatomic/Physiologic Issues and Imaging Findings/ Perfusion CT has the ability to detect ischemic stroke before it is Techniques: MRI and MR angiography (and to a lesser extent CT evident on noncontrast CT and can detect the infarct penumbra and CT angiography) are major imaging techniques used for representing viable parenchyma . If viable parenchyma is identi- assessment of these types of suspected CN V pathology . Each fied, vascular recanalization therapy may be initiated given the technique has its own set of advantages and disadvantages . patient meets additional criteria . Vascular recanalization therapy Location of lesions often leads to likely pathologic and clini- is not without risks, as severe intracranial hemorrhage is a poten- cal findings . tial outcome . This emphasizes the importance in not only identi- fying the presence or absence of acute ischemic stroke, but also Conclusion: The trigeminal nerve can be adversely affected by a identifying potential pitfalls and limitations of perfusion CT . Our wide variety of abnormalities . We review these along with the purpose is to provide an overview on imaging techniques, inter- clinical presentations to be expected . Preferred methods for pretation pearls and discuss common pitfalls and limitations we imaging and diagnosis are assessed . By combining clinical and encountered with CT perfusion . imaging data, optimal patient outcome is enhanced due to improved communication between physicians . Educational Goals/Teaching Points: The goals are to discuss the perfusion CT technique and perfusion CT parameters includ- ing; time-to-peak (TTP), cerebral blood volume (CBV), cerebral E419. Unusual and Usual Presentations of an Uncommon blood flow (CBF) and mean transit time (MTT); review the find- Entity: Tuberous Sclerosis ings in acute ischemic stroke and how to differentiate between Sathyakumar ,V.1; Shah, C.1,2; Ramakrishnaiah, R.1,2; Glasier, the core infarct (dead tissue) vs . the penumbra (hypoperfused C.2 1. University of Arkansas for Medical Sciences, Little Rock, AR; tissue); discuss common imaging pitfalls and limitations of per- 2. Arkansas Children’s Hospital, Little Rock, AR fusion CT, and provide a case-based pictorial essay discussing the Address correspondence to V. Sathyakumar (veenadoc@yahoo. effects of acetazolamide in perfusion CT . co.in)

Key Anatomic/Physiologic Issues and Imaging Findings/ Background Information: The purpose is to illustrate various Techniques: In this exhibit, a total of 11 cases (one normal and presentations of tuberous sclerosis, show progression of disease, 10 abnormal) of perfusion CT are reviewed . We present two compare and contrast various phakomatosis and provide differ- cases of hyperacute/acute stroke, two cases demonstrating mis- ential diagnosis of radiological findings seen in tuberous sclero- match defects identifying the penumbra, five cases of common sis . Tuberous sclerosis is a phakomatosis condition . This neurocu- pitfalls in perfusion CT imaging and one case demonstrating the taneous disease involves the brain, eye, kidney, heart, skin, bone effects of acetazolamide in perfusion CT for a patient with middle as well as lung . Typical presentation is subependymal nodules cerebral artery stenosis . An overview of the perfusion CT tech- and cortical tubers in a child with infantile spasm . We display nique, parameters utilized and image interpretation pearls will images showing different findings of tuberous sclerosis including also be discussed . cardiac rhabdomyoma . The exhibit includes a case that we have followed for years, which demonstrates increasing size of sub- Conclusion: Perfusion CT is proven to be a valuable tool in the ependymal giant cell astrocytoma that caused obstructive hydro- diagnosis of acute ischemic stroke . The knowledge provided by cephalus . We also show a case of lymphangioleiomyomatosis of these cases will not only allow the viewer to confidently identify the lung . We present various radiological findings seen in tuber- the presence of acute ischemic stroke, but also recognize the ous sclerosis patients on CT, MRI and ultrasound . We also discuss common pitfalls and limitations in perfusion CT . differential diagnosis of various lesions seen in tuberous sclerosis . Furthermore, we compare and contrast subependymal nodules and subependymal heterotopias . In addition, we briefly discuss E418. Imaging Review of the Trigeminal Pathway, other phakomatosis conditions like neurofibromatosis, Sturge Emphasizing Effects of Pathology on Anatomy and Resultant Weber syndrome, Von Hippel Lindau syndrome . We compare and Clinical Compromise contrast these various phakomatosis conditions . Palacios, E.; Rodgers, B. Tulane University, New Orleans, LA Address correspondence to B. Rodgers ([email protected]) Educational Goals/Teaching Points: The goals are to display multiorgan involvement with tuberous sclerosis; discuss differen- Background Information: The trigeminal pathway is long, and tial diagnosis of various radiological findings of tuberous sclero- abnormalities along its route can lead to a variety of sensory and sis, and compare and contrast various phakomatosis conditions . motor problems . Learning its course is the first step in under- standing the effects of disease . We will also review the clinical Key Anatomic/Physiologic Issues and Imaging Findings/ impact of CN V pathology on the patient . This presentation is Techniques: The exhibit will provide a description and pictorial also prepared as a teaching module for the general radiologist illustration of CT, MRI and ultrasound findings in tuberous sclero- and those in training . sis: cerebral findings (periventricular subependymal nodules,

317 El e c t r o n i c Ex h i b i t s : Neuroradiology cortical/subcortical tubers and subependymal giant cell astrocy- E421. Differential of Pineal Lesions Based on the New WHO tomas), renal angiomyolipoma, cardiac rhabdomyoma, pulmo- 2007 Classification: Radiologic-Pathologic Correlation (CME nary lymphangiomyolipoma, and display salient radiological fea- Credit Available) tures of other phakomatosis conditions . Juakiem, W.1; Smith, A.1,2; Smirniotopoulos, J.1; Rushing, E.2 1. Uniformed Services University, Bethesda, MD; 2. Armed Forces Conclusion: Revisiting radiological findings of tuberous sclerosis Institute of Pathology, Washington, DC and other phakomatosis conditions in a pictorial way may aid Address correspondence to A. Smith ([email protected]) residents and general diagnostic radiologists in becoming more comfortable at diagnosing these conditions . Background Information: In 2007 the WHO modified its classi- fication of lesions of the pineal region . We will illustrate the radi- ologic-pathologic features of neoplasms of the pineal region E420. The Limbic System: Anatomy of the Emotions (CME based on the new classification using images selected from an Credit Available) archive of pathologically proven cases . Whitehead, M.; Lee, B. University of Virginia, Charlottesville, VA Address correspondence to M. Whitehead ([email protected]) Educational Goals/Teaching Points: The educational goal of this is exhibit is for the viewer to develop a better understanding Background Information: The limbic system is a complex area of the various types of lesions that involve the pineal region, and of brain, intimately involved in emotional and autonomic equilib- to recognize the imaging characteristics of these lesions in order rium, memory, motivation, and personality . Despite its function- to narrow the differential diagnosis . al intricacies, the genesis of many of these intangible concepts have been mapped and localized to specific parts of the brain Key Anatomic/Physiologic Issues and Imaging Findings/ which are visible with MR imaging . The purpose of this exhibit is Techniques: Lesions of the pineal region have a limited differen- to review the anatomy and basic physiology of the seemingly tial diagnosis, which can be narrowed based on imaging findings mystical limbic system with emphasis on MR anatomy . along with the patient’s age, gender and laboratory values . Germ cell neoplasms (including germinoma, teratoma, and choriocarci- Educational Goals/Teaching Points: The function and location noma) account for 60% of the neoplasms occurring in the pineal of the various limbic system components visible on MR imaging region . The differential also includes the primary pineal neo- will be reviewed . Knowledge of limbic system anatomy enables plasms (pineocytoma, pineal parenchymal tumor of intermediate the radiologist to offer more specific diagnoses in specific symp- differentiation, pineoblastoma, and papillary tumor of the pineal tomatic clinical scenarios . gland) that make up 15% of pineal lesions, as well as astrocyto- ma, lipoma, meningioma and metastasis . The exhibit will focus Key Anatomic/Physiologic Issues and Imaging Findings/ on the CT and MR imaging findings with pathologic correlation . Techniques: The limbic system is intimately involved in the emo- tional experiences and human personality . It has a direct effect Conclusion: Pineal gland lesions present a differential that can on the diencephalon, influencing such things as homeostasis and be refined by knowledge of their specific imaging characteristics the fight or flight response . Some neuropsychiatric afflictions are along with patient history . directly related to limbic system disturbances . The functional and anatomic components of the limbic system including the limbic lobe and certain subcortical structures will be reviewed . The lim- E422. Temporal Bone Anatomy: A Pictorial Essay (CME bic lobe primarily includes the uncus, parahippocampal gyrus, Credit Available) cingulate gyrus, hippocampus, dentate gyrus, fornix, and fimbria . Smith, A.1,2; Smirniotopoulos, J.1,2 1. Uniformed Services Subcortical limbic structures include the mammillary bodies, University, Bethesda, MD; 2. Armed Forces Institute of Pathology, amygdala, and septal nuclei . T1-weighted, T2-weighted, and Washington, DC fluid attenuation inversion recovery (FLAIR) MR images have tra- Address correspondence to A. Smith ([email protected]) ditionally been the mainstay in evaluation and analysis of limbic system pathology . Diffusion tensor imaging provides exquisite Background Information: The temporal bone has complex anatomic detail . gross and imaging anatomy . When evaluating for pathology, this can be especially confusing to neophytes . However, an organized Conclusion: The limbic system is a key component of the review of this anatomy can help simplify the process, and pro- brain, important in human emotions, memory, motivation, and vides a greater understanding of the associated abnormalities personality . Familiarity with its various anatomic components and seen in disease . functions helps the radiologist prescribe more specific diagnoses . Educational Goals/Teaching Points: The goal of this exhibit is to enhance the viewer’s knowledge of the temporal bone anato- my in order to improve recognition of pathologic processes involving this region .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: This interactive review of the normal anatomy of the temporal bone, utilizing thin slice CT imaging in both the coronal and axial planes, will simplify and enhance understand- ing of this complex region . In addition, examples of both devel- opmental and pathological process will be highlighted by com- parison to normal images . 318 El e c t r o n i c Ex h i b i t s : Neuroradiology

Conclusion: Understanding of the anatomy of the temporal bone Educational Goals/Teaching Points: The goals are to review simplifies the detection and analysis of pathology in this region . the relevant anatomy pertaining to infections involving the orbit, ear, sinuses, and superficial/deep neck spaces; discuss the char- acteristic imaging features and clinical presentations of common E423. CT Evaluation of Chamberlain’s, McGregor’s and and uncommon head and neck infections, and illustrate key ana- McRae’s Skull Base Lines (CME Credit Available) tomic structures in the head and neck that determine the poten- Cronin, C.; Lohan, D.; Ni Mhuircheartaigh, J.; Meehan, C.; Murphy, tial patterns of disease spread and complications . J.; Roche, C. University College Hospital Galway, Galway, Ireland Address correspondence to C. Cronin (carmelcronin2000@hot- Key Anatomic/Physiologic Issues and Imaging Findings/ mail.com) Techniques: Selected cases of infections involving the pretrache- al, masticator, parapharyngeal, retropharyngeal, carotid and buc- Objective: The distance of the tip of the normal odontoid peg cal spaces will be presented, in addition to infections involving from Chamberlain‘s line was established on plain radiographs in the orbit, paranasal sinuses and tympanomastoid cavities . 1943 . To date these measurement have only been quantified on Complications discussed include: cavernous and sigmoid sinus MRI . CT’s technological ability has excelled over recent years . It thrombosis, intracranial abscess, Lemierre’s syndrome, now has excellent spatial resolution, speed and ability to perform Gradenigo’s syndrome, Pott’s Puffy tumor and Bezold’s abscess . high quality multiplanar reformats . It offers excellent bony detail, which many consider superior to that of plain radiographs and Conclusion: The imaging diagnosis of infections in the head and MRI . The purpose of this study is to evaluate the mean distance neck requires an understanding of the anatomic basis for the from the odontoid process of C2 to the standard skull base line: spread of infection and potential associated complications . Upon Chamberlain’s, McGregor’s and McRae’s lines on CT imaging, and the completion of this teaching module, the user will have to compare these measurements to previously documented plain learned a systematic approach for the evaluation of patients with radiograph and MRI measurements . head and neck infections based on an understanding of key ana- tomic structures in the various regions of the head and neck . The Materials and Methods: We retrospectively evaluated reformat- use of this approach will improve the ability for cross-sectional ted midline sagittal CT images of 150 adults . The shortest per- localization of infections and facilitate early detection of associat- pendicular distance was measured from the Chamberlain, ed complications . McGregor and McRae baselines for each subject to the odontoid tip and statistical analysis was performed to compare the CT data with the previously obtained MRI and plain film data . E425. Utility of PET-CT in the Surgical Management of Head and Neck Cancers: Combining Imaging Data With Images at Results: The mean position of the odontoid process was 1 4. mm Surgery below Chamberlain’s line (median=1 .2 mm, standard deviation Rodgers, B.; Friedlander, P.; Palacios, E.; Wasilewska, E. Tulane [SD] of 2 4. mm), 0 8. mm (median=0 9. mm, SD=3 mm) below University, New Orleans, LA McGregor’s line and 5 mm (median 5 mm, SD of 1 8. mm) below Address correspondence to B. Rodgers ([email protected]) McRae’s line . There is no significant difference between male and female results (p>0 05). or between these CT and previous MRI Background Information: In head and neck imaging, there is measurements (p>0 .05) . often a disconnect between what we see on a computer monitor and what the ENT surgeon sees in the operating room (OR) . This Conclusion: These results provide the mean and range of normal module should help imagers correlate our findings to surgical distance from the odontoid process to the most frequently used findings in the OR . Precise and accurate localization is vital as skull base lines on the current population on CT . Knowledge of part of surgical planning and intervention . the normal values will be of benefit to each radiologist in their everyday diagnosis and assessment of the skull base and aid Educational Goals/Teaching Points: For those imaging physi- establishment of the diagnosis of basilar impression . cians whose expertise lies outside of neuroradiology, head and neck anatomy can be very challenging . This is compounded by the challenges of interpreting both anatomic and physiologic E424. Head and Neck Infections: Patterns of Spread and data from PET-CT . Understanding the true needs of your referring Complications ENT surgeon will lead to more optimal therapy for the patient . Surapaneni, K.1; Reede, D.1; Smoker, W.2; Holliday, R.3; Gentry, L.4; Shatzkes, D.5 1. Long Island College Hospital, Brooklyn, NY; Key Anatomic/Physiologic Issues and Imaging Findings/ 2. University of Iowa Hospital and Clinics, Iowa City, IA; 3. New Techniques: The multiplanar anatomy of the head and neck with York Eye and Ear Infirmary, New York, NY; 4. University of emphasis on PET and CT imaging will be reviewed . The impor- Wisconsin Hospital and Clinics, Madison, WI; 5. St. Lukes- tance of accurate and precise interpretation will be demonstrat- Roosevelt Hospital Center, New York, NY ed . However, what does the ENT surgeon do with this informa- Address correspondence to K. Surapaneni ([email protected]) tion while performing a neck dissection? We have intraoperative photos from surgical cases that will provide additional examples Background Information: This exhibit reviews the clinical pres- of how we move from imaging to optimal surgical planning and entation, potential complications, imaging appearance, and basic management . anatomy as it pertains to the spread and/or containment of inflammatory processes in the head and neck . Conclusion: Surgeons and imagers do not always speak the same language . Patient care will be optimized when both types of physi- cians understand each others needs . Just saying where a mass or

319 El e c t r o n i c Ex h i b i t s : Neuroradiology node is located may be enough in many cases to guide a success- Educational Goals/Teaching Points: The goal is for the partici- ful surgery . In other cases, further communication and understand- pant of this educational activity to understand physiopathology, ing is required to avoid unnecessary dissection and fruitless sur- natural history, imaging presentation and differential imaging gery . This will lead to improved patient care and more referrals . diagnosis of otosclerosis; be able to formulate a differential diag- nosis for patients presenting with conductive hearing loss and normal otoscopy; identify critical CT findings affecting presurgical E426. Petrous Apex: Anatomy and Pathologies planning or predicting poor postsurgical outcome, and be aware Powell, A.; Kanekar, S.; Ghossaini, S.; Policare, C. Penn State of differential diagnosis in patients with poor postsurgical out- Milton S Hershey Medical Center, Hershey, PA come . Address correspondence to S. Kanekar ([email protected]) Key Anatomic/Physiologic Issues and Imaging Findings/ Background Information: Anatomically petrous apex is a por- Techniques: Preoperatively MDCT with MPR is accurate for iden- tion of temporal bone lying anteromedial to the inner ear tifying hypoattenuating otospongiotic plaques as well as known between the sphenoid bone anteriorly and occipital bone poste- predictors of less successful postsurgical outcomes, such as riorly . The tip of the petrous apex terminates at the foramen round window involvement and dehiscent tympanic facial nerve . lacerum . It has a close anatomic relationship with the carotid In patients with poor poststapedectomy outcome, MDCT evalu- canal and internal carotid artery, midbrain, pons and cranial ates for prosthesis displacement, intratympanic fibrosis, oblitera- nerves . Any pathology in the petrous apex could manifest into tive otosclerosis, malleoincudal dislocation, malleous ankylosis to various neurological and cranial nerve deficits . the tympanic wall, intravestibular prosthesis protrusion and reparative oval window granuloma . Educational Goals/Teaching Points: The goal is that the partic- ipant in this educational activity will learn the radiological anato- Conclusion: MDCT is useful in the diagnosis, pretreatment plan- my of petrous apex and its relationship with surrounding brain ning and postoperative evaluation of otosclerosis . structures and cranial nerves . The exhibit will highlight the impor- tance and salient differentiating points between the various petrous apex pathologies . E429. CT Perfusion Changes in Normal Tissues in Head and Neck Cancer Patients During a Course of Radiotherapy (CME Key Anatomic/Physiologic Issues and Imaging Findings/ Credit Available) Techniques: We retrospectively reviewed the imaging studies Saito, N.1; Truong, M.1; Wang, J.1; Lee, R.2; Tanabe, K.1; Ozonoff, from our PACS system of 22 patients with petrous apex lesion . All A.2; Sakai, O.1 1. Boston Medical Center, Boston University patients had a high resolution CT scan of the temporal bone and School of Medicine, Boston, MA; 2. Boston University School of contrast-enhanced high resolution MRI of the internal auditory Medicine, Boston, MA canal . Clinical features included cranial neuropathies, vertigo, diz- Address correspondence to N. Saito ([email protected]) ziness and fullness in the ear . Lesions are classified into anatomic variation (asymmetric fatty marrow, trapped fluid); infection Objective: The objective is to evaluate CT perfusion (CTP) (petrous apicitis, Gradenigo’s syndrome); cholesteatoma and parameters changes in the normal tissues during a course of con- cholesterol granuloma; neoplastic lesions (primary involving the current chemoradiotherapy in head and neck cancer patients . bone and secondary/metastasis to apex, and vascular . We illus- trate the imaging appearances of the various processes and dis- Materials and Methods: Nine patients with biopsy proven pri- cuss the clinical significance . mary head and neck cancer undergoing primary chemoradiation with curative intent were included in this study . Patients were Conclusion: Due to anatomical relations with internal carotid treated with conformal radiotherapy (RT) to a total dose of 70-72 artery, brainstem, and cranial nerves, pathologies involving Gy over 6-7 weeks . CTPs were obtained before RT, weeks two, petrous apex may cause a variety of neurological symptoms four, and six of RT, and six weeks after completion of RT . which are difficult to localize clinically and therefore imaging Perfusion parameters including blood flow (BF), blood volume plays a vital role . (BV), mean transit time (MTT), and capillary permeability (CP) were measured in the normal tissues (parotid gland, submandib- ular gland, sternocleidomastoid muscle, pharyngeal constrictor E427. MDCT Evaluation of Otosclerosis (CME Credit muscle, pharyngeal mucosa, and subcutaneous fat) within the Available) treated area using a deconvolution-based analysis . Rivas Rodriguez, F.; Gujar, S.; Shah, G.; Mukherji, S. University of Michigan Health System., Ann Arbor, MI Results: Nine patients completed five serial CTP studies accord- Address correspondence to F. Rivas ([email protected]) ing to the protocol . Primary tumor sites included: oropharynx (three patients), larynx (two), oral cavity (one), nasopharynx Background Information: Otosclerosis is a unique disease of the (one), hypopharynx (one), and auricle (one) . At weeks two, four, optic capsule and results from deposition of hypo-attenuating and six during RT and six weeks after RT, all CTP parameters spongy vascular bone . Lesions are most frequently seen in the were expressed as a percentage of the baseline values . For the anterior aspect of the oval window involving the fissula antefene- parotid gland, the mean percentage change of BF was 171 .5% strum (fenestral) with advanced cases involving the pericochlear (range: 130 .3-235 .4), BV was 162 0%. (139 3-223. .2), MTT was bone (retrofenestral) . Surgery for otosclerosis consists of stapedec- 104 .1% (57 .9-130 .9), and CP was 155 5%. (101 4-221. .3) . For the tomy and prosthesis insertion . We illustrate the spectrum of pre- sternocleidomastoid muscle, the mean percentage change of BF and postsurgical MDCT findings with multiplanar reformats (MPR) was 171 3%. (114 .3-193 .5), BV was 152 .4% (122 2-174. .1), MTT in a series of 30 patients with surgically proven otosclerosis . was 113 4%. (101 .0-124 .4), and CP was 545 .9% (178 .3-1240 9). .

320 El e c t r o n i c Ex h i b i t s : Neuroradiology

For the pharyngeal mucosa, the mean percentage change of BF E431. Paranasal Sinus Disease in Multiple Sclerosis– was 324 .4% (263 .8-371 .1), BV was 270 .5% (239 .7-314 1),. MTT Possible Links to Periodontal Disease and Parallels to this was 137 .9% (111 .1-171 .5), and CP was 4433 .2% (2,912 1-. in Other Autoimmune Diseases (CME Credit Available) 6798 .4) . In the parotid gland, muscles, BV demonstrated peak Rosenthal, P. Ralph H Johnson VA Medical Center, Charleston, SC increase at six weeks after RT and showed the lowest values at Address correspondence to P. Rosenthal ([email protected]) 2-4 weeks during RT . In the mucosa, however, BV increased at a median of six weeks during RT and showed the lowest values at Objective: The objective is to present the findings of paranasal six weeks after RT . BF increased the most at 4-6 weeks during RT sinus disease in a cluster of patients with imaging features of in all the tissues . Peak increase in MTT in salivary glands was at multiple sclerosis (MS) and correlate these findings with compa- six weeks, and 2-4 weeks during RT in all other normal tissues . rable appearances in patients with other autoimmune diseases . CP showed peak increase at six weeks after RT in salivary glands and muscles . Materials and Methods: This was a retrospective imaging review of a cluster of multiple sclerosis patients at a small south- Conclusion: Normal tissues such as parotid gland, muscle, fat, east center in the US showing variants of paranasal sinus disease . and mucosa demonstrated the increases in CTP parameters . There was correlation of these findings with MS disease activity These changes may reflect the onset of acute side effects of RT in this group, and correspondence of the sinus findings to imag- such as acute mucositis and acute changes in salivary flow . ing findings in a sampling of cases with other known autoim- mune diseases .

E430. The Retroantral Fat Pad: Important Landmark for Results: There was sequential findings in a patient with lupus Accurate Staging of Disease Extension Beyond the Maxillary and advanced osseous resorption around a maxillary tooth on CT, Sinus and Infratemporal Fossa with documentation of progression of sinus inflammation over a Kori, G.; Tu, R.; Brenner, C.; Jones, R.; Tanna, N.; Kambhampati, S.; few weeks as confirmed with MR . This shows the morphology of George Washington University, Washington, DC inferior maxillary sinus disease resulting from known periodontal Address correspondence to R. Tu ([email protected]) disease . Correspondence of the above findings in patients with multiple sclerosis and other patients with other autoimmune dis- Background Information: The early detection of pathology eases is demonstrated . The pattern and form of the inferior max- beyond the margins of the maxillary sinus laterally and infratem- illary sinus disease is analyzed . This shows inferiorly-localized or poral fossa craniad to Level II can be elusive . An understanding inferior-predominant maxillary sinusitis, with features of undulant of normal anatomic boundaries of the pterygopalatine fossa and and /or polypoid cystic changes of the sinus mucosa, and exam- retroantral space provides clues for accurate staging . We review ples of mild, moderate and severe, limited and extensive sinus normal anatomic landmarks of the infratemporal fossa and retro- involvements . The relationship of the sinus changes to MS dis- antral space . ease activity is not linear in this small sample, but the findings suggest an increased prevalence of this form of sinus disease in Educational Goals/Teaching Points: The reader will learn the patients with MS . normal landmarks of the infratemporal fossa and relationships of the retroantral fat pad . Variation of the retroantral fat pad will be Conclusion: The findings suggest that this variant of undulent or illustrated . Heightened understanding of subtle changes will aid polypoid, inferiorly-limited, or inferior-predominant, maxillary in accurate detection of early disease and prevent misinterpreta- sinus disease may be significantly more prevalent in patients with tion and understating of disease . MS than previously reported, and may be a marker of underly- ing maxillary ridge periodontal /gingival disease, even when the Key Anatomic/Physiologic Issues and Imaging Findings/ maxillary bone separating the dental ridge from the nasal sinus Techniques: The normal relationships of the retroantral fat pad has not been formally breached . space, the pterygopalatine fossa and infratemporal fossa are reviewed . Complex sinonasal inflammatory processes beyond the maxillary wall may be easily detected before extension into the E432. Experience with a Standard Head CT Trauma Report in pyerygoid muscles and infratemporal fossa occur . Level II inflam- a Deployed Military Hospital in Iraq (CME Credit Available) matory and neoplastic processes toward the skull base and Mackett, K.1; Sanghi, A.2; Folio, L.1 1. Uniformed Services sinuses may be identified by understanding the retroantral space University of Health Sciences, Bethesda, MD; 2. Walter Reed Army before the inevitable extension intracranially . Medical Center, Washington, DC Address correspondence to K. Mackett ([email protected]) Conclusion: The retroantral space is a normal anatomic space . The loss of normal fat is an early sign of disease . Various exam- Objective: A standard radiology reporting format is presented for ples of the retroantral space are reviewed . An understanding of penetrating head injuries based on recent deployed military the relationships of the space will aid in accurate interpretation experience . Standard reporting techniques helped communicate of sinonasal and head/neck pathology . complex CT findings to our deployed neurosurgeons in Iraq . The image severity findings of penetrating trauma on CT exhibited a predictable parallel clinical prognosis spectrum . Quantification and prognosis scores similar to Glasgow coma scale (GCS) and injury severity score (ISS) may be possible with similar standard formats used over time .

321 El e c t r o n i c Ex h i b i t s : Neuroradiology

Materials and Methods: Penetrating head trauma CT studies the volume transfer constant (ktrans), exchange rate (kep), elimi- were reviewed and correlated with example reports using a for- nation rate (kel) and arterial input function decomposed kep_adj mat that proved successful in a deployed military hospital in Iraq . and kpe_adj from an redefined Brix’s model . The results were The CT report format was compared to neurosurgical procedures correlated with prognostic tumor biomarkers, such as serum cal- and findings with other predictability measures to include GCS citonin level and tumor diameter, after RECIST measurement . and clinical follow-up of patients . Parameters on the standard report included presence or absence of the following: pneumo- Results: A total of 28 target lesions from 13 patients were evalu- cephalus, missile path (bihemispheric, multilobar, transventricu- ated . In 11 of 13 patients, follow-up scans after first treatment lar), skull fracture, evidence of elevated intracranial pressure revealed significant decrease of ktrans, kep, kep_adj and kpe_ (effaced sulci, basal cisterns, midline shift), hemorrhage (location adj (p<0 01). with an average decrease of -47%, -37%, -36% choices: cisternal, subarachnoid hemorrhage, intraventricular and -21%, respectively, which agreed with other biological read- hemorrhage, extra-axial), and intraparenchymal hemorrhage . outs . Two patients had increased follow-up values in the pharma- These parameters were arranged in a consistent table format cokinetic parameters, which also revealed either increased calci- with checklist type responses . tonin level or increased tumor diameter .

Results: Experiences in our deployed setting were positive as Conclusion: DCE-MRI of medullary thyroid carcinoma provides neurosurgeons, emergency department physicians and ICU medi- better signal to noise ratio, and spatial and temporal resolution cal staff could quickly assess the findings important to them . compared to previous studies at 1 .5T . Therapy monitoring of MTC Prior to this, neurosurgeons had to search for information buried using DCE-MRI at 3T provides a possibility to evaluate the biolog- in a nonstandard report . Standardized reporting of penetrating ic therapeutic responses by a clinically readily available approach . head injuries provided more efficient communication to neuro- DCE-MRI at 3T is a valuable diagnostic tool for monitoring the surgeons and other hospital medical staff over several months . microvascular properties of malignant tumors during therapy .

Conclusion: Standard reporting formats ensure evaluation of all significant penetrating head injury findings on CT and display E435. MR Imaging of Orbital Inflammatory Pseudotumor: A pertinent negative findings at a glance . Fast and efficient commu- Review and Update nication is essential to patient care in the chaotic setting of Sepahdari, A.; Aakalu, V.; Kapur, R.; Valvassori, G. University of deployed medicine . More objective severity determination and Illinois at Chicago, Chicago, IL prognostic indicators on CT may be possible in the near future . Address correspondence to A. Sepahdari ([email protected]) This reporting format may be generalizable to busy civilian trau- ma centers as well . Epidemiologic trends and preventive meas- Background Information: Orbital inflammatory syndrome (OIS), ures can be better evaluated and refined . Lastly, standard report also known as orbital inflammatory pseudotumor, can present mechanisms can make prospective research on CT grading scales with varied clinical and imaging findings . OIS can be difficult to possible for more consistent data mining of standard lexicon . distinguish from infectious lesions, from various benign and malignant neoplasms, and from other inflammatory lesions such as sarcoid or thyroid ophthalmopathy . We will present 15 cases E434. Dynamic Contrast-Enhanced MR Imaging of Medullary of proven OIS, with companion cases comprising infectious, Thyroid Carcinoma at 3T (CME Credit Available) inflammatory, and neoplastic lesions that mimic OIS . The pur- Sammet, S.; Liang, J.; Koch, R.; Yang, X.; Jia, G.; Shah, M.; Knopp, pose of our exhibit is to review the MRI findings of OIS, with a M. The Ohio State University, Columbus, OH focused description of key imaging findings and clinical context . Address correspondence to S. Sammet ([email protected]) Educational Goals/Teaching Points: The student should Objective: The purpose of this study was to investigate the become familiar with the range of clinical and imaging presenta- microcirculation changes of medullary thyroid carcinoma (MTC) tion of OIS . The student should be able to identify key features during antiangiogenic therapy with dynamic contrast-enhanced that can help distinguish OIS from mimicking lesions . MR imaging (DCE-MRI) at 3T . Key Anatomic/Physiologic Issues and Imaging Findings/ Materials and Methods: Thirteen patients (10 males, three Techniques: OIS can have a broad range of imaging findings, females) with metastatic medullary thyroid carcinoma in a Phase which will be reviewed . Diffuse orbital inflammation, preseptal II clinical trial of an RAF/VEGF-R kinase inhibitor underwent DCE- inflammation, periscleritis, lacrimal gland enlargement, myositis, MRI using Gd-chelate (0 .1 mmol/kg band width, flow 0 .5 ml/ and orbital mass with or without sclerosis have all been identi- second) on a 3T clinical MRI system . One baseline scan was per- fied as presentations of OIS . We will show high quality MRI formed prior to treatment and follow up scans (from one to eight examples of each, including a range of subtle to striking abnor- times, average three times) were scheduled after every eight- malities and companion cases of mimicking lesions . Several fea- weeks of therapy . A 3D radio frequency spoiled fast field echo tures may distinguish OIS from mimicking lesions . Sparing of the sequence was used for the dynamic scans: repetition time/echo myotendinous junction may suggest an alternative diagnosis of time: 8/4 milliseconds, fractional anisotropy: 20º, field of view: thyroid ophthalmopathy . Presence of an encapsulated, peripher- 250 mm; matrix: 256 × 256; slice thickness: 5 mm; 20 slices; ally enhancing fluid intensity lesion would indicate infectious cel- temporal resolution: 6 7seconds. with 70 time points . Contrast lulitis complicated by abscess . Diffusion-weighted imaging may enhancement in a region of interest (ROI) was evaluated by also be helpful, as intense diffusion restriction suggests a lym- quantitative pharmacokinetic parameters applying a two-com- phoid lesion whereas facilitated diffusion may suggest infectious partment model, which characterizes the angiogenic and micro- cellulitis . High quality orbital MRI can be rapidly performed with circulatory properties of the lesion, and enables quantification of the use of a multichannel head coil . Excellent fat-suppressed

322 El e c t r o n i c Ex h i b i t s : Neuroradiology postcontrast sequences with homogeneous fat suppression are E437. Postoperative Imaging in Carcinoma of Buccal Mucosa readily obtained with the head coil, and are useful for identifying Shah, S.; Walvekar, V.; Parekh, K.; Goswami, K. The Gujarat subtle disease . Cancer and Research Institute, Ahmedabad, India Address correspondence to K. Parekh (keyurparekh1983@yahoo. Conclusion: Orbital inflammatory syndrome can have a broad com) range of imaging and clinical findings which overlap with numer- ous other lesions . Awareness of the range of MRI findings in OIS Objective: The objective is to illustrate subtle changes pointing and key features that may distinguish OIS from mimicking lesions to recurrence and to highlight postoperative changes other than is essential in providing an accurate differential diagnosis . recurrence .

Materials and Methods: Thirty postoperative cases of malignan- E436. MR Evaluation of Orbital Pathology: A Pictorial cy of buccal mucosa were studied with CT and MRI . Characteristic Review Utilizing Knowledge of the Normal Structures of the features found on the images will be provided . Features will focus Orbit predominantly on the changes noted in the postoperative period . Yousefzadeh-Grunin, N.; Lignelli, A. New York Presbyterian Findings pointing to early recurrence at the operated site, like the Hospital- Columbia University, New York, NY abnormal mucosal pattern and enhancement of the suspected Address correspondence to N. Yousefzadeh-Grunin (noy9001@ lesion as compared to normal mucosa, are emphasized . The nyp.org) exhibit will include various postoperative cases, including those following wide excision and marginal resection . Background: The orbit is a relatively small anatomic space, but the site of a wide range of pathology, which can be distinguished Results: The presence of new lesions at previously operated site with dedicated MR imaging . In the approach to orbital pathology, shows more enhancement than surrounding normal mucosa . it can be helpful to consider the structures normally located with- Inhomogeneous enhancement of lesion favors early recurrence . in the orbit . These include the globe, optic and oculomotor The presence of enhancing soft tissue density lesions noted in nerves, extraocular muscles, vascular structures, and mucosal skin and subcutaneous plane indicates flap site recurrence . associated lymphoid tissue . The intent of this presentation is to Lesions mimicking recurrence in immediate postoperative period give an organized and illustrated approach to pathology encoun- either enhance similar or less than that of normal mucosa and tered in the orbit to make this small space a more welcome one points more in favor of postoperative changes like edema/inflam- to the practicing radiologist . mation . In the late postoperative period resected bone margins appearing sharp and the mucosa not showing any enhancement Educational Goals/Teaching Points: Educational Goals: The or irregularity rules out recurrence . goals are to briefly describe the normal anatomy of the orbit; describe the distinguishing MR appearance of pathology of the Conclusion: In cases where clinical examination is not fruitful in globe including retinoblastoma, melanoma, retinal detachment, postoperative evaluation, imaging has an important role . Imaging, and coloboma; describe the distinguishing MR appearance of immediate following the operation or later, holds due impor- pathology of the optic and oculomotor nerves including optic tance in terms of identifying altered but normal anatomical find- nerve infarct, optic neuritis, optic nerve glioma, meningioma, ings and early recurrence . Imaging can also guide the clinician for neurofibroma and schwannoma; describe the distinguishing MR further management options in terms of biopsy site to confirm appearance of diseases affecting the extraocular muscles includ- recurrence and adjuvant therapy . ing thyroid ophthalmopathy and myositis; describe the distin- guishing MR appearance of orbital vascular lesions including hemangioma, varix and lymphangioma; describe the distinguish- E438. The Facial Nerve: An Anatomic Review for the ing MR appearance of lymphoid tissue related lesions including Radiologist lymphoma, and leukemic infiltrate, and describe the distinguish- Whitehead, M.; Lee, B. University of Virginia, Charlottesville, VA ing MR appearance of additional lesions which may not fit neatly Address correspondence to M. Whitehead ([email protected]) in the above categories including rhabdomyosarcoma and der- moid/epidermoid . Background Information: The facial nerve (CN VII) serves sev- eral important functions: motor innervation for muscles of facial Key Anatomic/Physiologic Issues and Imaging Findings/ expression, taste sensation from the anterior tongue, and lacrimal Techniques: MR imaging is optimally suited for evaluation of gland parasympathetic supply . The purpose of this exhibit is pathology of the orbit . Reasons include the capability of multipla- to review the normal anatomic MRI appearance and course of nar imaging, the anatomic resolution, ability to differentiate tis- the facial nerve and its major branches . sue types, sensitivity to blood flow, and detection of phases of hemorrhage . Fat suppression techniques and contrast administra- Educational Goals/Teaching Points: The goals are to review tion are tools that improve accuracy of differential diagnosis . the normal course of the facial nerve, highlighting intra-axial, cis- ternal, intratemporal, and extracranial segments; to outline the Conclusion: Diagnosing pathology of the orbit can be a chal- normal enhancement pattern of CN VII, and to review the mus- lenging but satisfying process for the radiologist . Consideration of cular innervation and sensory input of CN VII . the structures of the orbit can help in arriving at a differential diagnosis . After locating a lesion within the orbit, specific imaging Key Anatomic/Physiologic Issues and Imaging Findings/ characteristics aid in making particular diagnoses within each Techniques: For evaluation of the facial nerve temporal segment, compartment . thin collimation temporal bone CT is the imaging modality of choice . For all remaining facial nerve segments, MRI is pre- ferred, because of the better contrast resolution . At our institu- 323 El e c t r o n i c Ex h i b i t s : Neuroradiology tion, T1-weighted, T2-weighted, fluid attenuation inversion recov- and results in significant morbidity and mortality . Long term ery, contrast-enhanced T1-weighted, and constructive interference sequelae include but are not limited to learning disabilities, mental in a steady state (CISS), a heavily T2-weighted imaging sequenc- retardation, epilepsy, diplegia or quadriplegia and cerebral es are used (images will be included) . The facial nerve emerges palsy . Reduced cerebral perfusion can occur from many factors from the brainstem at the pontomedullary junction . After an which may be prenatal, perinatal and postnatal . The pattern of cer- abbreviated trip through the cerebellopontine angle cistern, it ebral injury will depend on both the severity of ischemia and the courses in the anterosuperior compartment of the internal audi- gestational age of the infant at the time of insult . In addition, dif- tory canal, superior to the falciform crest and anterior to Bill’s bar . ferent patterns of injury have been shown to have differing long It then enters the labyrinthine, intratympanic, and mastoid seg- term sequelae involving motor function and cognitive impairment . ments of the temporal bone, giving off the greater superficial petrosal nerve, stapedial nerve, and chorda tympani . Finally, after Educational Goals/Teaching Points: The goals are to describe exiting the skull via the stylomastoid foramen, it terminates radic- the imaging characteristics of HIE with ultrasound, CT and MRI; ular branches supplying muscles of facial expression . Portions of emphasize the imaging findings on MR spectroscopy and per- the facial nerve, including the labyrinthine segment, geniculate fusion weighted imaging; and discuss the strengths and weak- ganglion, and proximal intratympanic segment may demonstrate nesses of available imaging modalities in evaluation of various variable degrees of enhancement in normal situations . patterns of HIE .

Conclusion: The facial nerve has multiple functions and a com- Key Anatomic/Physiologic Issues and Imaging Findings/ plex course . Familiarity of normal anatomy and appearance ena- Techniques: Different patterns of injury are observed that bles better recognition of CN VII pathology . depend on the degree of brain maturity and severity of the ischemic/hypoxic event . Patterns of injury in premature neonates (less than 34 weeks of gestational age) differ from term infants . E439. Intracranial Manifestations of HIV-Related Diseases Premature infants with mild events demonstrate periventricular Vaghani, A.; Kakarla, R.; Gorelick, G. Illinois Masonic Medical white matter injury, while those with severe HIE demonstrate Center, Chicago, IL injury to thalami, basal ganglia and brainstem . Term neonates Address correspondence to R. Kakarla ([email protected]) with mild HIE demonstrate predominantly watershed areas of injury, whereas patients with severe HIE demonstrate injury to Background Information: The purpose of this exhibit is to the thalami, basal ganglia, perirolandic cortex and brainstem . review the spectrum of intracranial diseases seen in HIV patients; is a convenient, low cost and noninvasive to explain the utility of CT and MRI in differentiating these modality for recognition of periventricular leukomalacia, hemor- pathologies, and to discuss the potential pitfalls and implications rhage and hydrocephalus . CT is a rapid modality for evaluation of of imaging findings in the patient care plan . hemorrhage and hydrocephalus . MRI is the most sensitive and specific modality for imaging of neonates with HIE . Modern imag- Educational Goals/Teaching Points: The exhibit will include: ing techniques like MR spectroscopy, diffusion-weighted imaging intracranial manifestations of HIV-related diseases (atrophy, mass and perfusion weighted imaging with relative cerebral blood flow lesions, white matter disease, leptomeningeal and ependymal (rCBF) and relative cerebral blood volume (rCBV) further potenti- disease); imaging characteristics (CT, MRI); imaging pitfalls; clini- ate the effectiveness of MR as a diagnostic and prognostic tool . cal implications of imaging, and future directions . Conclusion: Prompt, comprehensive and accurate evaluation of Key Anatomic/Physiologic Issues and Imaging Findings/ HIE is essential as different patterns of injury may be predictive Techniques: The exhibit will discuss intracranial manifestations of future motor and cognitive development and may guide reha- of HIV-related disease and atrophy, mass lesions, white matter bilitation . disease, and eptomeningeal and ependymal disease .

Conclusion: Familiarity with the various intracranial manifestations E441. Role of MDCT in Predicting Pre-Epiglottic Fat Invasion of HIV-related disease is essential to the workup and management in Supraglottic Malignancy (CME Credit Available) of HIV patients . The large overlap in the radiographic appearances Shah, S.; Parekh, K.; Walvekar, V.; Goswami, K. The Gujarat of these various diseases can make their differentiation difficult . An Cancer and Research Institute, Ahmedabad, India algorithmic approach based on radiographic signs of disease aids Address correspondence to K. Parekh (keyurparekh1983@yahoo. the radiologist in offering a more reliable list of differential diag- com) noses to the clinician to further direct patient management . Objective: The objective is to signify the role of MDCT in accu- rately predicting pre-epiglottic fat invasion ., and to illustrate find- E440. Multimodality Imaging Findings of Neonatal Hypoxic- ings favoring invasion of pre-epiglottic fat . Ischemic Encephalopathy Using Conventional and Modern Techniques (CME Credit Available) Materials and Methods: Thirty cases of supraglottic malignan- Akhter, N.; Saigal, G.; Lopez Arberola, R. Jackson Memorial cies were studied on MDCT . Changes in pre-epiglottic fat suggest- Hospital/University of Miami, Miami, FL ing malignant involvement were looked for . Findings were pres- Address correspondence to N. Akhter ([email protected]) ence of abnormal soft tissue enhancement in pre-epiglottic space, mass lesion invading pre-epiglottic space, cartilage Background Information: Neonatal hypoxic ischemic encepha- involvement, and altered pattern compared to opposite site in lopathy (NIE or HIE) results from systemic hypoxemia, reduced cases with hemilaryngeal involvement . Findings were correlated cerebral perfusion or both . It affects 2-9 of every 1,000 live births and confirmed by pathological and preoperative findings .

324 El e c t r o n i c Ex h i b i t s : Neuroradiology

Results: Our study revealed that involvement of pre-epiglottic fat E443. Imaging of Intradural Extramedullary Spinal Lesions involvement was confidently reported based on the following: (CME Credit Available) comparison with opposite side; presence of enhancing soft tissue Tuttle, D.; Sarang, T.; Ginat, D.; Meyers, S. University of Rochester, in pre-epiglottic space; mass lesion invading space or cartilage Rochester, NY involvement in relation to pre-epiglottic space . In early cases of Address correspondence to D. Tuttle ([email protected]. malignant involvement of pre-epiglottic space comparison with edu) opposite side turned out to be very simple and the most sensi- tive finding . Various false positive situations to be kept in mind Purpose: The purpose is to review the spectrum of intradural/ include: change in pre-epiglottic space by external pressure extramedullary spinal lesions . impression of mass lesion; presence of mucosal tissue within pre-epiglottic space; bilateral changes in pre-epiglottic space in Educational Goals/Teaching Points: The goals are to demon- early malignant lesions, and edematous epiglottis due to inflam- strate the imaging features of various intradural/extramedullary matory changes . A mass lesion involving lateral walls can lead to lesions involving the spine to aid the formulation of appropriate misdiagnosis . Small vascular channels noted in pre-epiglottic differential diagnosis . space turned out to be a nonspecific finding . Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: Invasion of pre-epiglottic fat in cases of supraglottic Techniques: An image-rich slide format will be employed to malignancy is significant in terms of the treatment protocol address the range of intradural/extramedullary spinal lesions, selected by the clinician . Accurate prediction on CT can prevent including common and rare diseases . Some of the diseases that further investigation in the form of an MRI study . Various situa- will be covered include congenital/developmental (arachnoid tions can mimic malignant involvement and careful evaluation cyst, , dermoid cyst, teratoma, neurenteric cyst, can prevent such pitfalls . dural ectasia, meningocele, dorsal dermal sinus, conjoined nerve roots); neoplastic (ependymoma [sporadic, neurofibromatosis Type II], schwannoma [sporadic, neurofibromatosis Type II], neu- E442. Chondrosarcoma of the Larynx: A Case Series rofibroma [sporadic, neurofibromatosis Type I], meningioma [spo- Theoret, C.1; Harder, S.2 1. Royal University Hospital, Saskatoon, radic, neurofibromatosis Type II], paraganglioma, primitive neur- Canada; 2. Loma Linda University Medical Center, Loma Linda, CA oectodermal tumor, malignant nerve sheath tumor, disseminated Address correspondence to C. Theoret ([email protected]) metastatic disease [central nervous system tumors, non-central nervous system metastases], leukemia, lymphoma); infectious Background Information: Although rare, laryngeal chondrosar- disease (pyogenic meningitis, granulomatous meningitis [TB, fun- coma is the most common sarcoma of the larynx . The purpose of gal], parasitic meningitis [cystercosis, etc .]); noninfectious inflam- this case series is to draw attention to this condition and to high- matory disease (adhesive arachnoiditis, sarcoidosis, inflammatory light some of the associated clinical and imaging features . reaction from subacute subarachnoid hemorrhage); vascular (dural arteriovenous fistula, arteriovenous malformation), and Educational Goals/Teaching Points: After reading this exhibit, traumatic (subarachnoid hemorrhage, avulsed nerve roots) . the reader should have an increased awareness of this entity; understand the importance of cross-sectional imaging in the Conclusion: The attendee will gain familiarity with the imaging diagnosis, surgical planning, and postoperative follow-up of laryn- characteristics of various intradural/extramedullary abnormalities geal chondrosarcoma, and understand that although imaging involving the spine that will allow the formulation of an appropri- findings are variable, classic features of chondrosarcoma seen in ate differential diagnosis . other locations may be identified in laryngeal chondrosarcoma .

Key Anatomic/Physiologic Issues and Imaging Findings/ E444. Imaging of Spinal Cord Lesions (CME Credit Techniques: The condition involves the components of the larynx Available) consisting of hyaline cartilage, including the cricoid cartilage, the Sarang, T.; Tuttle, D.; Meyers, S. University of Rochester, Rochester, thyroid cartilage, and the arytenoid cartilages . Laryngeal carcino- NY ma may be suspected clinically in a patient presenting with Address correspondence to T. Sarang (trushar_sarang@hotmail. hoarseness, dyspnea, dysphagia, or a neck mass . Endoscopic and com) histologic evaluation may be unremarkable or reveal vocal cord paralysis, a submucosal mass, or mucosal abnormality . Cross- Background Information: A wide variety of lesions can occur in sectional imaging may demonstrate the classic findings of chond- the spinal cord . Familiarity with the common types of lesions rosarcoma seen in other locations (stippled calcification, increased involving the spinal cord is useful to narrow the differential diag- signal on T2-weighted imaging) . Imaging also has a role in the nosis for intramedullary abnormalities . This presentation will evaluation of the extent of involvement of adjacent structures . begin with a review of spinal cord anatomy . The bulk of the Further, imaging studies may direct subsequent biopsy or may exhibit will review the spectrum of intramedullary spinal cord influence surgical management (conservative vs . radical resec- lesions including congenital anomalies, neoplastic disease, infec- tion), and are important in disease monitoring post-treatment . tious and noninfectious inflammatory disease, vascular and trau- matic lesions, and metabolic disorders . The presentation will be Conclusion: Radiologic imaging is important in the initial diag- image-rich with an emphasis on MRI and CT characteristics used nosis and the postoperative follow-up of laryngeal chondrosarco- to distinguish between disease entities . ma, which can at times be a difficult endoscopic diagnosis . This rare entity may show the classic imaging characteristics of chond- Educational Goals/Teaching Points: After viewing the exhibit rosarcoma seen elsewhere in the body . the participant will be familiar with common intramedullary

325 El e c t r o n i c Ex h i b i t s : Neuroradiology spinal cord disease with specific emphasis on key MRI and CT enhancement . Flow voids related to abnormal enlarged vessels findings; be able to distinguish different disease entities, and be may also be seen, and are a more specific finding for vascular able to formulate a concise differential for a given lesion . anomalies . In particular, identifying the site of a nidus or shunt can aid in distinguishing the type of vascular lesion . Angiography Key Anatomic/Physiologic Issues and Imaging Findings/ permits confirmation of the pattern of abnormal vessels and is Techniques: An image-rich slide format will be employed to vital to treatment planning . cover the intramedullary spinal cord lesions . Some of the diseas- es that will be covered include congenital (myelocele/myelom- Conclusion: Acute or chronic myelopathy may be due to vascu- eningocele, myelocystocele, lipomyelocele/lipomyelomenin- lar lesions, including spinal cord infarct, spinal dural arteriov- gocele, spinal cord lipoma, tethered spinal cord, split spinal cord enous fistula, spinal cord arteriovenous malformation, and spinal malformations/diastematomyelia, syringohydromyelia [with Chiari cord arteriovenous fistula . In these clinical scenarios, vascular 1 malformation], neurenteric cyst, terminal ventricle); neoplastic lesions of the spinal cord may or may not be suspected by lesions (astrocytoma, pilocytic astrocytoma, anaplastic astrocyto- the referring physician . It is important that radiologists be familiar ma, glioblastoma multiforme, ependymoma [sporadic, associated with these entities and their MR appearance, and that they rec- with neurofibromatosis type II], hemangioblastoma [sporadic, ommend angiography when necessary to ensure appropriate multiple lesions in von Hippel Landau disease], ganglioglioma/ diagnosis and treatment . gangliocytoma, metastasis, malignant glioneuronal tumor); infec- tions (pyogenic, granulomatous infection, including tuberculosis and fungal infections, sarcoidosis, parasitic, viral [cytomegalovirus, E446. Cystic Lesions of the Spine: Location-Based herpes, polio], vacuolar myelopathy in AIDS); noninfectious Differential Diagnosis with Emphasis on Key Distinguishing inflammatory lesions (multiple sclerosis, transverse myelitis, sys- Imaging Features temic lupus myelitis); vascular lesions (spinal cord infarct, venous El-Sherief, A.1; Malhotra, A.1; Westesson, P.1; Kathuria, S.2 1. congestion in spinal cord/intradural vascular malformation, arteri- University of Rochester, Rochester, NY; 2. Johns Hopkins, ovenous malformation with or without intramedullary hemato- Baltimore, MD ma, cavernous hemangioma); traumatic lesions (spinal cord con- Address correspondence to A. El-Sherief (ahmed_elsherief@urmc. tusion, spinal cord transaction, traumatic intramedullary hemato- rochester.edu) ma, post-traumatic syrinx), and metabolic (subacute combined degeneration) . Background Information: The purpose of this education exhibit is to review the macroanatomy of the spine: meninges, spaces/ Conclusion: The attendee will be able to recognize the charac- compartments and contents; review location-based differential teristics of various spinal cord abnormalities to enable formula- diagnosis of cystic lesions of the spine, and review key imaging tion of an appropriate differential diagnosis . findings that aid one in arriving at an accurate pathoanatomic diagnosis .

E445. Vascular Lesions of the Spinal Cord: MR Imaging with Educational Goals/Teaching Points: The viewer will be able to Angiographic Correlation (CME Credit Available) apply macroanatomy of the spine with special attention to its Yousefzadeh-Grunin, N.; Reig, B.; Silver, J. New York Presbyterian compartments and contents; develop a location-based differen- Hospital-Columbia University, New York, NY tial diagnosis when encountering a cystic lesion in the spine, and Address correspondence to N. Yousefzadeh-Grunin (noy9001@ recognize key imaging findings that aid one in arriving at an nyp.org) accurate pathoanatomic diagnosis .

Background Information: Vascular lesions of the spinal cord Key Anatomic/Physiologic Issues and Imaging Findings/ include spinal cord infarct, spinal dural arteriovenous fistula, spinal Techniques: The exhibit will focus on macroanatomy (meninges, cord arteriovenous malformation, and spinal cord arteriovenous spaces/compartments and contents); intramedullary (syringomy- fistula . Patients with these lesions may present clinically with elia, hydromyelia, ventriculus terminalis, cystic spinal tumor acute or chronic-progressive myelopathy . A spectrum of clinical [astrocytoma, ependymoma, hemangioblastoma]); intradural and radiographic findings of these lesions is presented, highlight- extramedullary (spinal meningeal cyst, nerve sheath tumor ing features which favor each diagnosis . Additional intramedullary [schwannoma], neurenteric cyst); extradural (spinal meningeal lesions, which may mimic vascular lesions are also discussed . cyst, sacral meningomyelocele, facet joint synovial cyst, idiopathic spinal cord herniation, aneurysmal bone cyst) . Teaching Points: The exhibit will describe the vascular supply to the spinal cord and how it affects the distribution and appear- ance of vascular lesions of the spinal cord; review the clinical E447. Imaging Complications of Epidural Injections presentation of vascular lesions of the spinal cord and how the Silbergleit, R.; Greene, R.; Khan, N.; Krishnan, A. William presentation can help to differentiate the various types; illustrate Beaumont Hospital, Royal Oak, MI the MR features of vascular lesions of the spinal cord with angio- Address correspondence to R. Silbergleit (rsilbergleit@beaumont. graphic correlation, and identify additional intramedullary lesions edu) which can mimic some of the MR features of vascular lesions . Background Information: Epidural injections are commonly Key Imaging Findings: The primary imaging finding of vascular used for treatment and occasionally diagnosis of back pain and/ lesions of the spinal cord is intramedullary hyperintensity on or radiculopathy . These injections are usually safe, however, a T2-weighted MR imaging from cord ischemia and edema . This variety of serious complications can occur . may also be associated with expansion of the cord and/or

326 El e c t r o n i c Ex h i b i t s : Neuroradiology

Educational Goals/Teaching Points: The objectives are to dem- Educational Goals/Teaching Points: The goals are to illustrate onstrate that a variety of serious conditions can result as a com- the pathophysiology and imaging findings of LCH in CNS includ- plication of epidural injections and to demonstrate the imaging ing craniofacial structures; meninges and other extra-axial struc- appearance of these conditions . tures, and intra-axial (direct involvement, indirect/neurodegener- ative lesions) . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Epidural Injections can be complicated by a variety Key Anatomic/Physiologic Issues and Imaging Findings/ of conditions including epidural hematoma, epidural abscess, Techniques: The etiology of LCH-CNS remains poorly under- epidural granulomatous processes, and discitis/osteomyelitis . stood . The majority of patients display more than one type of MRI is usually the best imaging modality for diagnosing these lesion . Often diabetes insipidus with structural changes in the complications and guiding further therapy . CT myelography can hypothalamic-pituitary region heralds the involvement of other be used if there is a contraindication to MRI . parts of the brain, sometimes by years . The clinical presentation is largely dependent on the predominant type of lesion . Conclusion: It is important to be aware of the potential for seri- ous complications as a result of epidural injections . MRI is useful Conclusion: LCH is a systemic disease that could involve multi- in identifying these complications . ple systems and organs in the body . Here we provide a compre- hensive spectrum of imaging findings of LCH applicable to CNS .

E448. Lipomatous Lesions of CNS and Spine Midia, M.; Ribeiro, L.; Kirby, J.; Miller, E.; Maizlin, Z. McMaster, E450. Analysis of Ulcerated Carotid Plaque: Comparison Burlington, Canada Between MDCT Angiography and Color Doppler Ultrasound Address correspondence to M. M idia ([email protected]) (CME Credit Available) Saba, L.; Mallarini, G. A.O.U, Cagliari Sardegna, Italy Background Information: This exhibit will classify and describe Address correspondence to L. Saba ([email protected]) the imaging pattern of lipomatous lesions in the central nervous system (CNS) and spine . We aim to provide essential background Objective: The purpose of our work was to assess the diagnostic information necessary and focus on a practical approach and key efficacy of MDCT angiography (MDCTA) in the study of patients imaging findings that are pertinent to the clinician and patient with carotid plaque complicated by ulceration, through the com- management . parison with the color Doppler ultrasound (CD-US) and the sur- gical observation in a cohort of 180 patients . Educational Goals/Teaching Points: The goals are to describe the lipomatous lesions based on origin, location, clinical signifi- Materials and Methods: From January, 2004 to December, cance, associated lesions and imaging pitfalls, and to offer a 2007, 198 patients for a total of 396 carotid arteries were ana- practical algorithm to image and assess these lesions . lyzed by using MDCTA, studied at first through CD-US . We meas- ured the degree of stenosis based on North American Key Anatomic/Physiologic Issues and Imaging Findings/ Symptomatic Carotid Endarterectomy Trial criteria . In each patient Techniques: Fat could be found in a variety of neoplastic and we evaluated plaque composition and presence of ulcerations . non-neoplastic lesions . Understanding the embryology and tissue Maximum intensity projection, multiplanar reconstruction and differentiation/transformation is essential in being able to inter- volume rendering postprocessing were performed . Obtained data pret such lesions accurately in the CNS and spine . Also utilizing a were compared with the surgical results . multimodality approach and paying attention to locations of these lesions are the key factors that need to be considered by Results: MDCTA detected 73 ulcerations; the surgical confirma- every radiologist . tion has underlined a 92 6%. sensitivity, clearly superior to 61 7%. detected by color Doppler ultrasound . We observed that the Conclusion: Detecting fat continues to be a helpful feature in number of ulcerations increased with the severity of stenosis . interpretation of a variety of lesions and disorders of the brain Ulcerations of the carotid plaque occur more often proximal than and spine . Here we have outlined the key information necessary distal to the point of maximum stenosis . Moreover, we found to image and assess fatty lesions of the CNS and spine with the that fatty plaques are more likely affected by ulcerations whereas modern tools and techniques available . calcified plaques are rarely ulcerated .

Conclusion: MDCTA is a very good technique in detecting plaque E449. Histiocytosis: Imaging Spectrum in the Central ulcerations whereas CD-US shows suboptimal results . MDCTA Nervous System allows for adequate assessment of the morphology of the ulcer- Midia, M.; Kirby, J.; Miabi, Z.; Chhibber, S.; Jeddyian, S.; Miller, E.; ated plaque, defining dimension, position and the structure of Haider, E. McMaster University Hospital, Hamilton, Canada plaque . Address correspondence to M. Midia ([email protected])

Background Information: Langerhans cell histiocytosis (LCH) is a clonal proliferative disease of the dendritic cell system . We present the imaging pattern of LCH involving the craniofacial structures and the central nervous system (CNS) .

327 El e c t r o n i c Ex h i b i t s : Neuroradiology

E451. Carotid Artery Wall Thickness and Enhancement Results: Measurements of the distal common CAWT varied from Patterns of the Vascular Wall by Using MDCT Angiography 0 .5 to 1 5. mm . We observed that hypertension and diabetes melli- (CME Credit Available) tus are associated with increased CAWT (p=0 016. and p= 0 0188. Saba, L.; Caddeo, G.; Mallarini, G. A.O.U, Cagliari Sardegna, Italy respectively) . We did not find a significant association between Address correspondence to L. Saba ([email protected]) increased CAWT with dyslipidemia and a history of smoking .

Objective: The purpose of this study was to evaluate the correla- Conclusion: Results of our study suggest that an increased CAWT tion between the carotid artery wall thickness (CAWT) and the is associated with the cardiovascular risk factors hypertension enhancement patterns of the vascular wall by using MDCT angi- and diabetes . This data should be considered in the stratification ography (MDCTA) . risk and for the follow up of these patients .

Materials and Methods: Forty-three patients (31 males, 12 female; mean age 60 years; age range 45-82 years), for a total of E453. Incidence of Carotid Artery Disease in Patients 86 carotids were prospectively analyzed by using a four-detector Screened for Liver Transplantation: Assessing Risk Factors row CT . Contrast material was injected into the antecubital vein and Clinical Significance (CME Credit Available) and arterial phase images were obtained by using a 4 mL\sec- Jurasic, M.; Broderick, D. Mayo Clinic Jacksonville, Jacksonville, FL ond flow rate . In each patient CAWT was measured by using a Address correspondence to M. Jurasic ([email protected]) digital caliper . Differential enhancement of the vascular wall was measured after and before contrast material administration by Objective: The objective is to determine the incidence of carotid using the same region of interest area in all patients; absolute artery disease detected on screening carotid Doppler ultrasound enhancement was also recorded . The normality of each continu- in liver transplantation candidates . Risk factors will be evaluated ous variable group was tested using the Kolmogorov-Smirnov Z in order to optimize screening techniques . Post- transplant clini- test . Concordance correlation coefficients were calculated by cal outcomes will also be assessed, with a focus on cerebral vas- using Pearson statistics . cular events, to determine the incidence of these events follow- ing liver transplantation in patients with carotid artery disease . Results: In our study CAWT ranged from 0 .54 to 1 .57 mm, with a mean value of 0 .914 mm . In the Kolmogorov-Smirnov Z test, Materials and Methods: A total of 744 patients evaluated for normality of variable was accepted for the CAWT values liver transplantation between 1998 and 2006 were randomly (p=0 .368) . Correlation coefficient r between CAWT and absolute selected . Patients who received prescreening carotid Doppler enhancement values was 0 .0729 (95% CI from -0 .1412 to ultrasound were included in this study, and retrospectively evalu- 0 .2804) with p=0 .5048 . Correlation coefficient r between CAWT ated for risk factors for carotid artery disease, including age, sex, and differential enhancement values was 0 1738. (95% CI from smoking history, hypertension (HTN), diabetes (DM), abnormal -0 .0396 to 0 3720). with p=0 .1096 . lipid panels, and carotid bruits . Clinical outcomes, including pre- transplant carotid artery surgery or stenting, and cerebral vascular Conclusion: Our results indicated that there is not a statistically events occurring during and following transplantation, were also significant correlation between CAWT, absolute carotid wall investigated . enhancement and differential carotid wall enhancement by using MDCTA . Results: Of the 744 patients evaluated, 440 underwent pretrans- plant screening carotid Doppler ultrasound . Of these 440, 384 received liver transplants . 5 .7% of screened patients had signifi- E452. Association Between Carotid Artery Wall Thickness cant findings on carotid Doppler: 19 had moderate narrowing, two and Vascular Risk Factors (CME Credit Available) of which also had vertebral artery disease; six had severe narrow- Saba, L.; Sanfilippo, R.; Montisci, R.; Mallarini, G. A.O.U, Cagliari ing, of whom one underwent pretransplant carotid endarterecto- Sardegna, Italy my (CEA) . Of these patients, 72% were male, 60% smoked, 8% Address correspondence to L. Saba ([email protected]) had HTN, 28% had DM, 16% had HTN and DM, and 8% had abnormal lipid ratios . The average age of patients with greater Objective: Carotid artery wall thickness was indicated as a mark- than mild carotid disease was 62 years, vs . 59 for those with mild er of atherosclerosis . The aim of this paper was to determine if or no disease . Of patients without significant carotid disease, 70% carotid artery wall thickness (CAWT) evaluated by using MDCT were male, 73% smoked, 18% had HTN, 20% had DM, 13% had angiography (MDCTA) is associated with the classic vascular risk HTN and DM, and 13% had an abnormal lipid ratio . factors (hypertension, diabetes mellitus, dyslipidemia, history of smoking) . Conclusion: The incidence of significant carotid artery disease with >70% narrowing was low (1%) in this population of individ- Materials and Methods: This was a retrospective study and we uals being evaluated for liver transplantation, despite the high analyzed 168 patients by using a multidetector row CT scanner . frequency of risk factors conditions, including tobacco use, diabe- In each patient we measured CAWT and measurements were tes, and hypertension . Only one person with significant disease made with an internal digital caliper . Continuous data were and a history of transient ischemic attacks underwent CEA prior described as the mean value ± standard deviation (SD) and they to transplantation, and none of the patients with moderate or were compared with Student t test . We performed simple logistic severe stenosis or vertebral artery disease experienced intra- or regression in order to evaluate the association between hyper- immediate postoperative ischemic events . These findings suggest tension, diabetes mellitus, dyslipidemia, a history of smoking and that narrower screening with carotid ultrasound, focusing on IMT . P<0 .05 was considered to indicate statistical significance . patients with bruits, multiple risk factors, and prior cerebral vas- cular events, may be reasonable and safe .

328 El e c t r o n i c Ex h i b i t s : Neuroradiology

E454. Artery of Adamkiewicz Evaluated by Using MDCT the stereotaxic space icbm152 . Finally, lesion probability maps Saba, L.; Mallarini, G. A.O.U, Cagliari Sardegna, Italy voxel by voxel were generated for each MS subgroup . These Address correspondence to L. Saba ([email protected]) were then compared visually .

Objective: Arteries of Adamkiewicz (AKA) feed the anterior spi- Results: The lesion load was higher in SP (range 4 .8-74 .97 cm3; nal artery (ASA) and the anterior two thirds of the spinal cord mean ± SD of 28 .49 ± 19 .7) than RR (0 .82-53 .93 cm3; 14 .59 ± receive blood supply from the ASA . It is extremely important to 12 .9) and PP (2 .5-35 33. cm3; 10 .27 ± 11 .4), p<0 .001, and no study the AKA in order to avoid ischemic complication of spinal difference was seen between RR and PP . Except for higher lesion cord after surgery of the thoracoabdominal aorta . Our purpose load in the posterior fossa and basal ganglia/internal capsules in was to evaluate the visualization of the AKA by using MDCT angi- SP patients, there was no evident visual difference in the spatial ography (MDCTA) . distribution of MS plaques in the different clinical groups .

Materials and Methods: We retrospectively studied CT data set Conclusion: The spatial distribution of MS plaques differs exclu- of 80 patients that underwent an MDCTA examination of the tho- sively in the basal ganglia, internal capsules and posterior fossa racoabdominal aorta, and we analyzed the AKA presence and of SP when compared with RR/PP patients . This suggests that characteristics . Contrast material was injected into the antecubital spatial distribution may play a role, at least in SP patients, but it vein and arterial phase images were obtained by using a 4-6 mL\ is not the determinant factor in the clinical long-term evolution of second flow rate . For each patient we generated postprocessed MS patients . Invisible white matter disease, as well as cortical images by using maximum intensity projection (MIP), multiplanar and spinal involvement may be more important factors for chron- reconstruction (MPR) and volume rendering (VR) techniques . ic progression . Each exam was evaluated by two radiologist independently .

Results: We visualized at least a single AKA in 63 (78 75%). of E456. T1 and T2 Relaxation Times in Multiple Sclerosis the 80 patients . We identified two arteries of Adamkiewicz in Patients Before and After GadodiamideContrast Injection at nine (11 25%). . The most number of AKA had their origin 3T (CME Credit Available) between T9 and L1: 57 arteries (80 .3%) . Forty-eight AKA origi- Sammet, S.; Koch, R.; Liang, J.; Jia, G.; Knopp, M. The Ohio State nated from the left side (67 .6%) . University, Columbus, OH Address correspondence to S. Sammet ([email protected]) Conclusion: MDCT angiography may depict artery of Adamkiewicz in a high percentage of patients and its sensitivity is Objective: The purpose of this study was to evaluate T1 and T2 comparable to MR and digital subtraction angiography . relaxation time changes in white matter lesions and in normal appearing white matter (NAWM) in multiple sclerosis (MS) E455. Visual Assessment of the Spatial Distribution of patients before and after the injection of a Gd-chelate at 3T . Multiple Sclerosis Plaques and its Impact in the Clinical Presentation of Multiple Sclerosis Patients (CME Credit Materials and Methods: In this ongoing study 42 patients (37 ± Available) 9 years) with prior diagnosed multiple sclerosis were scanned in Ribeiro, L.1; Matos, A.2; Narayanan, S.3; Arnold, D.3; Santos, A.4 a 3T clinical MR scanner (Philips Healthcare, Cleveland, OH) with 1. McMaster University, Hamilton, Ontario, Canada; 2. No an 8-channel SENSE head coil . T1 measurements with a multiflip Institutional Affiliation; 3. McGill University, Montreal, Canada; 4. angle sequence (flip angle=5, 10, 15 and 20o; TR=50 0millisec- Faculty of Medicine Ribeirao Preto, USP, Ribeirao Preto, Brazil onds; TE=10 milliseconds) and T2 measurements with a multi- Address correspondence to L. Ribeiro ([email protected]) shot turbo spin echo sequence (10 TE values from 12 to 120 mil- liseconds; TR=2,000 milliseconds) were performed before and Objective: Multiple sclerosis (MS) is the most common demyeli- after injection of a single dose of gadodiamide (GE Healthcare, nating disorder affecting the central nervous system (CNS) in Princeton, NJ) . T1 and T2 parameter maps were generated to adults . A total of 85% of the patients will present with a relaps- determine pixel-wise MR relaxation times in the brain tissue of ing remitting course (RR), and 10 years after disease onset, up to the patients . Average relaxation times in MS lesions were calculat- 50% of these will develop progressive neurological decline, i e. ,. ed by drawing regions of interest and compared to normal secondary progressive phase (SP) . Fifteen percent of patients will appearing white matter before and after contrast injection . present with primary progressive MS (PP) . The factors that deter- mine which subtype of disease evolution a patient will have are Results: Average T1 in enhancing MS lesions before contrast not well understood . It is reasonable to believe that the white injection was 1,204 ± 238 milliseconds and 1,354 ± 265 milli- matter lesion load, which is higher in SP, could at least partially seconds in nonenhancing lesions . Gadodiamide shortened T1 to explain the disease course seen in these patients . There have an average of 755 ± 164 milliseconds after contrast injection in been few attempts to investigate if the spatial distribution of MS enhancing lesions and to 1,300 ± 254 milliseconds in nonen- plaques differs between different MS groups . The objective of hancing lesions . Before contrast injection, NAWM in MS patients this study is to assess whether there is a significant difference in showed a T1 of 867 ± 62 milliseconds and T1 shortened to 840 the spatial distribution of MS plaques among the different MS ± 62 milliseconds after contrast injection in MS patients . T2 clinical groups . before contrast injection was 116 ± 23 milliseconds in enhancing and 122 ± 27 milliseconds in nonenhancing MS lesions . After Materials and Methods: Retrospective images from 50 MS contrast injection T2 changed to 117 ± 28 milliseconds in patients were analyzed . MS plaques were automatically segment- enhancing MS lesions and to 122 ± 26 milliseconds in nonen- ed and manually corrected, producing lesion labels . Intra- and hancing lesions . intersubject linear and nonlinear registration was applied using

329 El e c t r o n i c Ex h i b i t s : Neuroradiology

Conclusion: Relaxation time changes in the normal appearing E458. Advanced MRI Techniques in Neuroradiology: white matter of MS patients after the injection of gadodiamide Principles, Applications and Future Directions -contrast media at 3T could help to attribute the changes to (CME Credit Available) either diffuse abnormality or to small lesions undetected at lower Srinivasan, A.; Wesolowski, J.; Shah, G.; Chenevert, T.; Mukherji, S. field strengths . Evaluating MR relaxation time changes after gado- University of Michigan Health System, Canton, MI diamide injections at 3T can potentially contribute to an earlier Address correspondence to A. Srinivasan ([email protected]) detection of MS lesions and help to better understand the patho- genesis of the disease . Background Information: This exhibit will review the principles of advanced MRI techniques in neuroradiology including diffu- sion and perfusion imaging, tractography, functional diffusion E457. Evaluation of a New CT Metal Artifact Correction mapping, MR spectroscopy, dynamic MRA and functional MRI; Postprocessing Algorithm in Neuroradiology: Preliminary discuss their clinical applications with supporting data from the Results (CME Credit Available) literature, and teach about the potential future applications . Douglas-Akinwande, A.1; Brown, K.2; Jennings, S.1; Ho, C.1 1. Indiana University School of Medicine, Indianapolis, IN; 2. No Educational Goals/Teaching Points: The participant in this Institutional Affiliation activity will learn the principles of advanced MRI techniques in Address correspondence to A. Douglas-Akinwande (andougla@ neuroradiology, including diffusion and perfusion imaging, trac- iupui.edu) tography, functional diffusion mapping, MR spectroscopy, dynam- ic MRA and functional MRI; gain awareness of their clinical appli- Objective: The objective is to evaluate a new postprocessing cations in multiple neurologic disorders including but not restrict- algorithm on metal related artifacts on MDCT images in head, ed to stroke, demyelinating disease, vascular diseases, brain neck and spine studies . tumors and epilepsy, and be exposed to the latest research appli- cations of these techniques . Materials and Methods: Nine MDCT examinations of the brain, ear, nose and throat (ENT), and spine in which metal was Key Anatomic/Physiologic Issues and Imaging Findings/ present were studied . The image data was postprocessed with a Techniques: The principles included in this exhibit include diffu- new image based metal artifact reduction algorithm that does sion-weighted and diffusion tensor imaging including tractogra- not require raw data and is applied following CT image recon- phy, functional diffusion mapping, perfusion-weighted imaging, struction . The original and postprocessed images were independ- dynamic MR angiography, MR spectroscopy, and functional MRI . ently compared by two neuroradiologists in a nonblinded man- The clinical applications discussed include acute stroke, brain ner using a five-point scale (1=definitely better, 2= better, 3=no tumors, demyelinating disorders, epilepsy, degenerative disorders, change, 4= worse, and 5=definitely worse) . The parameters rated eg ., Parkinson’s disease, vascular diseases, and miscellaneous . included the visualization of bone and soft tissues within 1cm Future directions include the use of advanced MRI in cognitive and 5 cm of metal, reduction of artifacts from metal, and disorders and exploring impaired consciousness . improvement in diagnostic quality . The presence of new artifacts and the demonstration of new anatomy were assessed . Conclusion: Advanced MRI techniques are becoming increasing- ly important in the diagnosis, prognostication and follow-up of Results: The CT images from four ENT, three brain, and two multiple neurological diseases . Knowledge of the principles and spine examinations were studied . Processing revealed new anat- applications of these techniques in the clinical setting will be omy in 8/9 cases; reduced metallic artifacts in 4/9 cases; helpful for both radiologists-in-training and practising radiologists . improved visualization of soft tissue within 1 cm and 5 cm in 4/9 and 5/9 cases respectively . The visualization of bone within 1cm and 5 cm improved in 2/9 and 1/9 cases . The diagnostic E460. “CHAFT” A Differential Diagnosis of Low T2 Signal quality of the study improved in 3/9 cases . The metal artifact Intensity Lesions in Neuroimaging (CME Credit Available) correction technique was most effective in ENT cases where visu- Hsu, J.; York, G.; Mansfield, L.; Lisanti, C. Brooke Army Medical alization of soft tissue within 5 cm and 1 cm of metal was better Cneter, Fort Sam Houston, TX in 4/4 and 3/4 cases respectively . The visualization of bone, soft Address correspondence to J. Hsu ([email protected]) tissue and the appearance of artifacts were rated as unchanged or worse in most brain and spine cases . New artifacts were intro- Background Information: 1 . To review MR physics of low signal duced in all cases . intensity on T2 weighted imaging . 2 . To introduce mnemonic “CHAFT” to guide differential when evaluating lesions with low Conclusion: This preliminary study demonstrates the usefulness signal intensity on T2WI . 3 . To give a comprehensive list of of this new metal correction algorithm which revealed new anat- lesions that have dark signal on T2WI with selected examples omy in 89% of cases; and was most effective in ENT cases where seen in neuro-imaging . the visualization of soft tissue improved in 75-100% of cases within 1cm and 5 cm of metal . The algorithm is novel because it Educational Goals/Teaching Points: Review MR physical basis can be applied retrospectively following image reconstruction for low T2 signal . Present “CHAFT” mnemonic for lesions with and may reduce radiation dose to ENT patients by replacing the low signal intensity on T2WI (Calcifications, Hemosiderin/High current practice of repeat scanning of the oral cavity at a different iron, Air and Artifact, Fibrous lesions and Flow voids, and gouty angle to avoid dental hardware . Despite revealing new anatomy, Tophi) . This exhibit will review selected illustrative cases of more the generation of new artifacts in brain and spine cases did not common causes of low T2 lesions in neuro-imaging and applica- result in improved diagnostic quality and further optimization of tion of the “CHAFT” mnemonic this algorithm is needed for brain and spine examinations .

330 El e c t r o n i c Ex h i b i t s : Neuroradiology

Key Anatomic/Physiologic Issues and Imaging Findings/ were highly-significantly preferred by experienced, blinded readers . Techniques: Low T2 signal on MR are seen in tissues with low These findings may be attributed to the approximately 25-30% proton density, superparamagnetic effect, and low cellularity . greater enhancement seen with this agent due to weak binding to There are a number of pathologic conditions which can result in serum proteins . References: 1) Colosimo C, Invest Radiol decreased T2 signal . The use of “CHAFT” mnemonic is helpful in 2001;36:72-81 . 2) Colosimo C, Neuroradiology 2004;46:655-665 . neuroimaging by providing a list of differential diagnoses when 3) Knopp MV, Radiology 2004;230:55-64 . 4) Maravilla KR, presented with lesions demonstrating low T2 signal . Imaging Radiology 2006:289-400 . 5) Rowley H, AJNR 2008 . In Press . examples of each of the mnemonic components will be pre- sented . E462. Contrast-Enhanced MR Neuroimaging Protocols at Conclusion: Low signal intensity on T2 weighted MR images is a 1.5T and 3T: Results of an Expert Consensus Panel helpful tool in narrowing differential diagnosis in neuroimaging . Kuhn, M.1; Rowley, H.2; Tanenbaum, L.3; Enterline, D.4 1. “CHAFT” is a mnemonic to facilitate rapid recall of different MRI Southern Illinois University School of Medicine, Springfield, IL; 2. etiologies for low signal on T2WI . This exhibit presents common University of Wisconsin, Madison, WI; 3. Mt. Sinai School of T2 dark lesions and application of the “CHAFT” mnemonic in Medicine, New York, NY; 4. Duke University Medical Center, neuroimaging . Durham, NC Address correspondence to M. Kuhn ([email protected])

E461. Results of Intraindividual Crossover Comparisons of Background Information: The objective is to develop state-of- Gadobenate Dimeglumine with Other Gadolinium Contrast the-art contrast-enhanced MR neuroimaging protocols that are Agents for MRI of the Central Nervous System optimized for the specific examination being performed and the Kuhn, M.1; Rowley, H.2; Colosimo, C.3; Essig, M.4; Maravilla, K. 5 field strength being used . 1. Southern Illinois University School of Medicine, Springfield, IL; 2. University of Wisconsin, Madison, WI; 3. Catholic University of Educational Goals/Teaching Points: A multi-institutional panel Sacred Heart, Rome,Italy; 4. German Cancer Research Center, of expert neuroradiologists was convened to evaluate and dis- Heidelberg, Germany; 5. University of Washington, Seattle, WA cuss MR neuroimaging protocols at 1 .5 and 3T . All participants Address correspondence to M. Kuhn ([email protected]) used 1 .5T as well as 3T machines in their research and clinical practice . Together, the experts developed protocols for commonly Background Information: The objective is to summarize intrain- performed studies (whole brain, spine, neurovascular, acute dividual crossover comparison studies of gadobenate dimeglu- stroke, and multiple sclerosis) as well as for several more special- mine vs . comparator agents for MRI of central nervous system ized indications (IAC and cranial nerve, orbits, pituitary, and sei- (CNS) lesions . zures) . For each technical parameters (ie, FOV, TR, TE, ETL, NEX, etc), an absolute value or range of values was specified . Each Educational Goals/Teaching Points: All patients (n=336) protocol also included a recommended slice thickness and gap, underwent two separate MR exams within 2-14 days of each plane(s) of reconstruction, and notes on any special sequences other . In a randomized order, all patients received 0 .1 mmol/kg (IR, fat saturation, magnetization transfer) the group felt should of gadobenate dimeglumine and either gadolinium diethylenetri- be recommended or discouraged . In the absence of a complete aminepentaacetic acid (n=191), gadolinium diethylenetri- consensus on a particular exam, annotations captured possible aminepentaacetic acid bismethylamide, (n=117), or gadoterate variations on approaches suggested by the panel . All recom- meglumine, (n=28) . Expert neuroradiologists assessed both sets mended protocols were subsequently tested and further opti- of T1-weighted spin echo postcontrast images qualitatively mized as necessary prior to finalization . assessed in a blinded manner . Quantitative region of interest measurements of lesion to normal background brain data were Key Anatomic/Physiologic Issues and Imaging Findings/ also derived by blinded readers . Differences in study populations Techniques: Optimized neuroimaging protocols which are appli- were assessed with the Wilcoxon signed rank test . cable at multiple institutions were developed and will be pre- sented . Protocols at 3T were optimized to take advantage of the Key Anatomic/Physiologic Issues and Imaging Findings/ high SNR provided by these systems while considering SAR Techniques: Gadobenate dimeglumine resulted in significantly issues . For the majority of contrast-enhanced MR examinations, a greater (p<0 .05) lesion-to-brain contrast than comparator agents standard dose of 0 .1 mmol/kg bodyweight is recommended in all five studies . In blinded reader evaluations, a highly signifi- however, this dose may be reduced with the use of a high-relax- cant (p<0 .001) preference for gadobenate dimeglumine over the ivity contrast agent . For certain exams at 1 .5T (for example, pitui- other three gadolinium based contrast agents was noted for tary lesions and acoustic neuromas) and for many studies per- lesion detection and global diagnostic preference . In patients formed on a 3T scanner, a half dose of 0 .05 mmol/kg body- with poorly enhancing lesion such as metastases, gadobenate weight was felt to be adequate, particularly when a higher-relax- dimeglumine resulted in the detection of lesions not seen on the ivity contrast agent was used . comparator exams . Conclusion: Neuroimaging protocols optimized for the type of Conclusion: Results from intraindividual studies involving 336 examination being performed and for the coil and field strength patients undergoing MRI of the CNS show that gadobenate of the scanner being used have been developed . The use of dimeglumine is more efficacious than other gadolinium agents at high-relaxivity contrast agents provides adequate enhancement an equivalent dose . In general, images produced following admin- at a lower dose, maximizing contrast enhancement and patient istration of gadobenate dimeglumine demonstrated greater con- safety . trast enhancement, provided more diagnostic information, and

331 El e c t r o n i c Ex h i b i t s : Neuroradiology

E463. Pros and Cons of Cone-Beam CT: What the Radiologist Results: Overall, lesions had highest contrast on WHAT . The high Has to Know (CME Credit Available) spatial resolution and excellent grey matter/white matter contrast Tanabe, K.1; Nishikawa, K.1; Otonari-Yamamoto, M.1; Sano, T.1; allowed depicting a number of juxtacortical lesions and a few Wang, J.2; Nadgir, R.2; Saito, N.2; Sakai, O.2 1. Tokyo Dental GM lesions . WHAT images also provided excellent depiction of College, Chiba, Japan; 2. Boston University/Boston Medical perivascular spaces . SWI magnitude images depicted only 93% of Center, Boston, MA the lesions seen on WHAT . This is due to the decreased contrast Address correspondence to K. Tanabe ([email protected]) in the weakly proton density weighted SWI magnitude images compared to WHAT . SWI phase images showed several interest- Background Information: Cone-beam CT is an imaging tech- ing features . Some lesions were seen on the magnitude images, nique utilized worldwide, particularly in the field of dental medi- but not on the phase images indicating that contrast in these cine, but remains unfamiliar to radiologists in the United States . lesions is due to free water increase . Other lesions were seen The purpose of this exhibit is to review the principle of cone- only on phase but not magnitude images . These lesions must beam CT; to review use of cone-beam CT for dental implant have significant presence of paramagnetic material, e .g . iron . planning; to review common dental pathologies on cone-beam Furthermore, a dark outer ring was observed on some lesions on CT, and to discuss pros and cons of cone-beam CT . SWI phase images that was not visible in SWI magnitude or WHAT images, and most lesions visible on SWI magnitude and Educational Goals/Teaching Points: The major teaching points phase images were associated with venous vasculature . of this exhibit are to learn the principle of cone-beam CT; to understand advantages and limitations of cone-beam CT, and to Conclusion: This ongoing study indicates that 7T MRI provides be familiar with cone-beam CT findings of common dental several novel contrast mechanisms not typically visible at 1 .5T for pathologies . detailed characterization of MS lesions and depiction of their internals structure . Future studies are needed to correlate the var- Key Anatomic/Physiologic Issues and Imaging Findings/ iable 7T MRI appearance of MS lesions with clinical findings . Techniques: The exhibit will include principles of cone-beam CT High resolution MR imaging at 7T MRI enables to differentiate (techniques, spatial resolution, radiation dose, limitations); a substructures in MS lesions . Therefore, ultra-high field MRI of review of cone-beam CT findings of odontogenic and nonodon- MS might help to better understand the course of the disease togenic lesions with sample cases (periodontal disease, such as and monitor treatment . periapical granuloma, periapical abscess or , trau- ma, such as fracture, tooth subluxation, odontogenic cysts, odon- togenic tumors, nonodontogenic cysts, nonodontogenic tumors); E466. Imaging of Neurocutaneous Syndromes (CME Credit dental implant planning with cone-beam CT (scan and recon- Available) struction techniques, interpretation: pertinent findings–what the Parmar, H.; Ibrahim, M. University of Michigan, Ann Arbor, MI dentist wants to know, pitfalls), and discussion of advantages Address correspondence to H. Parmar ([email protected]) and disadvantages of cone-beam CT . Background Information: Neurocutaneous malformations or Conclusion: Cone-beam CT has been utilized worldwide, partic- phakomatoses constitute a wide and often complex spectrum of ularly in the field of dental medicine . Understanding its advantag- congenital abnormalities affecting multiple structures, especially es and limitations is crucial for optimal patient care . of ectodermal origin like the nervous system, skin and retina . Some other visceral organs are involved to a lesser degree . Imaging, especially MRI, is extremely helpful in the workup of E465. Multiple Sclerosis Lesion Characterization with MRI at these patients and in certain cases can be vital for accurate diag- 7T (CME Credit Available) nosis before the clinical features become apparent . Secondly, Sammet, S.; Schmalbrock, P.; Shah, J.; Boster, A.; Chakeres, D.; identification of many of the responsible genes has vastly Racke, M.; Knopp, M. The Ohio State University, Columbus, OH improved our understanding of these entities . The purpose of Address correspondence to S. Sammet ([email protected]) this exhibit is to discuss and describe the common and some of the uncommon types of neurocutaneous syndromes; to review Objective: The objective is to evaluate 7T MRI for visualizing and the imaging findings of these entities using a variety of imaging characterizing multiple sclerosis (MS) lesion substructure with modalities with particular focus on MRI, and to develop an imag- the long-term goal to bring 7T MRI into clinical practice thus ing based approach to these complex entities . expanding capabilities for early diagnosis and treatment assess- ment . Educational Goals/Teaching Points: After completing this exhibit, the viewer will be able to recognize the typical imaging Materials and Methods: Ten MS patients (33-53 years) were features associated with various neurocutaneous malformations studied at 7T (Philips Healthcare, Cleveland, OH) using the fol- and understand their underlying pathology . lowing sequences: 2D-susceptibility weighted imaging (SWI: rep- etition time [TR]/ echo time [TE]/flip=1,600/12/50°); 2D-white Key Anatomic/Physiologic Issues and Imaging Findings/ matter attenuated inversion recovery turbo spin echo (WHAT: TR/ Techniques: This exhibit will provide an overview of clinical and TI/ TE=8,000/500/14) and T2-weighted gradient spin echo imaging features of various neurocutaneous syndromes seen in (GraSE: TR/TE=4,000/70) . Phase images were reconstructed from regular radiology and neuroradiology practice . They will be divid- the SWI data . All 7T MR images were visually compared and the ed into the first group of relatively common entities like: neurofi- numbers of lesions seen with each sequence were counted . bromatosis type I and type II, tuberous sclerosis, Sturge-Weber syndrome and von Hippel Lindau syndrome . Next we will present

332 El e c t r o n i c Ex h i b i t s : Nuclear Medicine imaging findings in some of the rare and uncommon types of neurocutaneous syndromes like neurocutaneous melanosis, Nu c l e a r Me d i c i n e /Mo l e c u l a r Proteus syndrome, basal cell nevus syndrome (Gorlin’s syn- drome), hereditary hemorrhagic telangiectasia (Osler-Weber- Im a g i n g Rendy syndrome) and hypomelanosis of Ito . E468. Common Artifacts in Nuclear Medicine: Diagnosis, Prevention and a Pictorial Review 1 2 1 1 E467. The New Great Mimicker: Disseminated Girard, P. ; Lefkovitz, Z ; Finestone, H. ; Elgort, S . 1. Coccidiomycosis (CME Credit Available) Maimonides Medical Center, Brooklyn, NY; 2. Mount Sinai Yost, A.; Gridley, D.; Bollepalli, S.; Keehn, B. Maricopa Medical Medical Center, New York, NY Center, Phoenix, AZ Address correspondence to P. Gerard ([email protected]) Address correspondence to A. Yost ([email protected]) Background Information: It is important to be aware of the Background Information: Coccidioidomycosis (valley fever) is a various artifacts encountered in nuclear medicine as they can systemic fungal infection caused by Coccidioides immitis endem- result in misdiagnosis . We present a pictorial of commonly ic to Arizona, Southern California and Northern Mexico . The clini- encountered nuclear medicine artifacts that can result in misdiag- cal syndrome presents as community-acquired pneumo- nosis and decrease diagnostic accuracy . Awareness of these arti- nia with various immunologic manifestations such as rashes and facts will result in better patient care and outcomes . skeletal discomfort . Although, most infections resolve without complications or antifungal therapy, coccidioidomycosis may Educational Goals/Teaching Points: We will discuss the com- spread hematogenously to other parts of the body in approxi- mon causes for encountering artifacts in nuclear medicine, dis- mately 1% of infected individuals-higher in the immunocompro- cuss artifact presentations on the nuclear study, and provide mised . Disseminated coccidiomycosis (DC) is defined as coccidi- ways to avoid the pitfalls when it comes to interpretation of oidal disease that spreads beyond the pulmonary parenchyma or these studies . We will discuss how quality control plays an hilar nodes . Few studies exist that examine DC’s imaging presen- important role in the production of artifacts . With improved tation and morbidity . The purpose of this exhibit is to define detection and understanding of these artifacts, patient care can our experience with DC from a county hospital’s perspective . The be improved . Phoenix hospital’s population is composed of the incarcerated, illegal aliens, and the severely mentally ill . These individuals gen- Key Anatomic/Physiologic Issues and Imaging Findings/ erally receive inadequate health care and are often immunocom- Techniques: We will review a variety of commonly encountered promised . DC is a mimicker in its presentation often involving the artifacts in nuclear medicine including: artifacts produced by neuroaxis, musculoskelatal system, and abdomen much the attenuation and technical problems, contamination artifacts, same way that syphillis and tuberculosis can present in con- instrument malfunction, operator error, artifacts produced by founding patterns . Its indolent characteristics make it complex to overlying objects, patient related artifacts, problems with radiop- diagnose . For two primary reasons, DC is a differential to consid- harmaceuticals, nuclear cardiology artifacts, etc . er across the United States, despite its proclivity and concentra- tion in the San Juaquin Valley . Our mobile society allows for Conclusion: Artifacts remain an issue in the correct interpreta- exposure to occur with presentation months to years later, when tion of nuclear medicine studies . Distinction of artifacts from nor- a person resides in a nonendemic area . Secondly, the increasing mal variants and pathologic entities may be a difficult task . If an life expectancy of those who are immunocompromised continues artifact is not recognized during acquisition and interpretation of to expand . Consideration of disseminated cocci in the differen- a study, it can simulate a pathologic process and lead to a misdi- tial for a patient may be a life-saving measure as a radiologist . agnosis . We will display and discuss a variety of commonly encountered artifacts, discuss how to recognize these artifacts Educational Goals/Teaching Points: The goals are to delineate and demonstrate techniques in awareness and prevention to the complex and myriad imaging presentations of DC; review enhance patient care . DC’s epidemiology, serology, treatment, and sequelae, and utilize a case-based, interactive learning model to enhance user reten- tion . E469. Outside the Box: Unexpected Crucial Findings In The Daily Practice of Nuclear Medicine 1 3 1 2 1 Key Anatomic/Physiologic Issues and Imaging Findings/ Gerard, P. ; Lefkovitz, Z. ; Kleyn, M. ; Geller, M. ; Desai, K. 1. Techniques: The exhibit will demonstrate imaging characteristics Maimonides Medical Center, Brooklyn, NY; 2. Winthrop University of DC presentation with MR and CT; review the optimum imag- Hospital, Mineola, NY; 3. Mount Sinai Medical Center, New York, ing sequences utilizing MRI, and discuss important diffential con- NY siderations . Address correspondence to P. Gerard ([email protected])

Conclusion: Disseminated coccidiomycosis is indolent and myri- Background Information: The objective is to discuss the identi- ad in presentation . Its increasing incidence and necessity to fication of crucial incidental findings on nuclear medicine studies treat make it an important diagnosis to consider from an imaging that can have devastating consequences if they are not detect- perspective . ed . To show clinicians how thinking “outside the box,” can help solve these critical problems from a new perspective .

Educational Goals/Teaching Points: There are many different studies that are performed daily in a busy nuclear medicine department . In the early evaluation of the patient, the nuclear 333 El e c t r o n i c Ex h i b i t s : Nuclear Medicine medicine study may be the initial diagnostic examination as it They are phagocytozed by macrophages which accumulate with- offers both anatomic and functional information . Although per- in lymph nodes . Disturbances in lymph flow or in nodal architec- formed for other reasons, there may be crucial incidental findings ture caused by metastases lead to abnormal patterns of accumu- that require prompt diagnosis and communication to the refer- lation of the particles, which are detectable by MRI . On postcon- ring physician . These findings can have devastating consequences trast T2- and T2*-weighted MRI benign lymph nodes show a if not detected . We discuss our experience in a variety of nuclear drop in signal intensity and homogenous darkening whereas medicine studies, including PET-CT where incidental critical find- areas of malignant infiltration show lack of nanoparticle uptake ings were diagnosed changing patient management, and we and remain signal-intense . elaborate on key points to help diagnose these important find- ings . Conclusion: By taking this quiz the viewer will acquire confident knowledge of the features of benign vs . malignant lymph nodes Key Anatomic/Physiologic Issues and Imaging Findings/ in lymphotropic nanoparticle-enhanced MRI . Techniques: Many nuclear medicine studies are requested as they convey both anatomic and functional information on a vari- ety of disease entities . A variety of nuclear medicine studies E471. Pictorial Review of Unexpected Extraosseous Findings obtained from our nuclear medicine department will be present- on Skeletal Scintigraphy (CME Credit Available) ed which demonstrate crucial incidental findings, requiring Webb, H.; Oza, U.; Latifi, H.; Grossman, S.; Joyner, K.; Griffeth, L. prompt communication to the referring physician . These cases Baylor University Medical Center, Rockwall, TX include abdominal aortic aneurysms on gastrointestinal bleeding Address correspondence to H. Webb ([email protected]) studies, pneumothorax or tumor on VQ lung and PET-CT scans, DVT and pericardial effusions on PET-CT, compartment syndrome Background Information: The goal of this exhibit is to show the on bone scan, pancreatitis and aneurysms and diverticulitis on reader unexpected and often unusual findings when interpreting PET-CT scans, the misdiagnosis of brown fat in the cancer skeletal scintigraphy . The categorized format of this presentation patient, lung tumors on cardiac scans, technical artifacts and will aid the reader in establishing a broad classification of etiolo- attenuation defects, etc . gies for these extraosseous findings .

Conclusion: Nuclear medicine procedures are performed daily to Educational Goals/Teaching Points: Although the exact mech- diagnose a variety of clinical conditions . It is important to be anism for extraosseous uptake on skeletal scintigraphy is not fully aware of unexpected crucial findings that are encountered that understood, the cases presented will be organized into separate require prompt identification and communication of the findings categories based on underlying etiology . These categories include to the referring physician . We demonstrate how thinking “outside artifact, excretory abnormalities, neoplastic conditions, hormonal the box” can help demonstrate a variety of these incidental conditions, inflammation, ischemia/infarction, and trauma . nuclear findings and show how it affects diagnosis and patient Correlative radiologic imaging as well as histopathologic and clin- management issues . ical findings will be incorporated in several cases . Key teaching points will be highlighted in each case .

E470. Quiz Yourself in Lymph Node Characterization With Key Anatomic/Physiologic Issues and Imaging Findings/ Lymphotropic Nanoparticle-Enhanced MRI Using Techniques: This exhibit will address the incidental extraosseous Superparamagnetic Iron Oxides! (CME Credit Available) uptake of tracer on skeletal scintigraphy, focusing on the com- Islam, T.1; Braschi, M.1; Oliveira, G.2; Harisinghani, M.1 1. Center mon and uncommon imaging findings with pathologic correla- for Molecular Imaging Research/Massachusetts General Hospital, tion . Boston, MA; 2. Massachusetts General Hospital, Boston, MA Address correspondence to T. Islam ([email protected]. Conclusion: Unexpected extraosseous skeletal scintigraphic find- edu) ings often cause diagnostic dilemmas . Participating in a pictorial review of several examples in multiple broad categories of diag- Background Information: The purpose of this education exhibit nostic etiologies should allow the reader to create more accurate is to familiarize viewers with various patterns of enhancement interpretations . in lymphotropic nanoparticle-enhanced MRI (LNMRI) with feru- moxtran-10 using test cases . E472. The Utility of Bone Scintigraphy in Pediatric Patients Educational Goals/Teaching Points: Evolving technologies (CME Credit Available) such as LNMRI with ferumoxtran-10 improve the accuracy in dis- Zukotynski, K.1,2; Treves, S.1,2; Grant, F.1,2 1. Harvard Medical tinguishing benign from malignant lymph nodes . However accu- School, Brookline, MA; 2. Children’s Hospital Boston, Boston, MA rate nodal characterization requires reader training and experi- Address correspondence to K. Zukotynski (katherine.zukotynski@ ence . This exhibit will showcase the variations in signal intensity utoronto.ca) changes with ferumoxtran-10 in benign and malignant nodes . Multiple histologically proven lymph nodes from various primary Background Information: Bone scintigraphy is a sensitive imag- tumors will be shown pre- and postcontrast enhancement in a ing modality for the detection of osseous abnormalities . It may be quiz manner followed by the correct answers . used to detect initial changes that can not be identified with ana- tomic imaging, such as early bone stress in patients actively Key Anatomic/Physiologic Issues and Imaging Findings/ involved in sports . It may complement findings identified on radio- Techniques: This technique employs superparamagnetic iron graphs, CT or MRI such as in the evaluation of patients with neo- oxide nanoparticles targeted at the reticuloendothelial system . plastic disease . A three-phase bone scan may be an effective

334 El e c t r o n i c Ex h i b i t s : Nuclear Medicine approach in the evaluation of suspected septic arthritis or osteo- stress syndrome (shin splints) . These can be seen earlier than on myelitis . Bone scintigraphy offers advantages compared with ana- radiography, often at presentation . Reflex sympathetic dystrophy tomic imaging in that it provides a practical way of imaging the classically demonstrates increased blood flow to the affected limb entire skeleton and typically does not require sedation . However, with periarticular uptake . Prosthetic joints can also be evaluated interpretation of pediatric bone scintigraphy may pose particular for aseptic loosening . This however needs to be distinguished challenges, such as those related to developmental change and from osteomyelitis and septic arthritis, which can be achieved disease distribution in children . This exhibit will review the utility with radiolabeled leukocyte and bone marrow imaging . Soft tis- of bone scintigraphy in modern pediatric musculoskeletal imaging . sue uptake can also be demonstrated in nonmalignant lesions, including post-traumatic myositis ossificans, heterotopic ossifica- Educational Goals/Teaching Points: The goals are to review tion and soft tissue calcification in a patient with scleroderma . the utility of bone scintigraphy in pediatric musculoskeletal imag- ing with emphasis on the appearance of tracer uptake associated Conclusion: Skeletal scintigraphy has numerous applications with specific pathology and pitfalls encountered in imaging chil- beyond evaluation for metastatic disease . Knowledge of the vari- dren . ety of non-neoplastic bony processes along with their typical dis- tribution and differentiating features can aid radiologists in accu- Key Anatomic/Physiologic Issues and Imaging Findings/ rate interpretation and diagnosis . Techniques: Whole-body planar bone scans, pinhole images and SPECT will be shown for the evaluation of traumatic, neoplastic and infectious abnormalities in children . Imaging protocols used E474. F-18 FDG PET-CT Imaging of Benign and Malignant will be reviewed . Musculoskeletal Diseases (CME Credit Available) Nguyen, B.; Roarke, M.; Ram, P. Mayo Clinic, Scottsdale, AZ Conclusion: This is a didactic exhibit illustrating key imaging Address correspondence to B. Nguyen ([email protected]) findings and the utility of pediatric bone scintigraphy . Background Information: F-18 FDG PET-CT is a well-established imaging modality for the staging and post-therapeutic surveil- E473. Skeletal Scintigraphy of Benign Bone Lesions lance of lymphoma, melanoma, and cancer of the lung, esopha- (CME Credit Available) gus, colon and breast . The imaging is based on uptake and Velayudhan, V.; Ferretti, J.; Cardoza, S.; Rosen, J. Nassau retention of glucose-analog radiotracer by highly metabolic University Medical Center, Copiague, NY tumors and related metastases . During this combined anatomic Address correspondence to V. Velayudhan ([email protected]) and functional evaluation of malignancy, musculoskeletal pathol- ogy may be purportedly or fortuitously demonstrated . In this Background Information: Skeletal scintigraphy with methylene exhibit, the authors present the spectrum of benign and malig- diphosphonate is most commonly performed in evaluation for nant musculoskeletal processes encountered during PET-CT metastatic disease . Frequently, benign conditions are incidentally imaging . detected . Bone scintigraphy can be helpful in the differentiation of these benign abnormalities . Educational Goals/Teaching Points: This exhibit reviews the PET-CT features of benign and malignant musculoskeletal diseas- Educational Goals/Teaching Points: The goals are for the par- es . Emphasis is on the differentiation between benign lesions ticipant in this educational activity to differentiate benign condi- requiring no intervention and malignant tumors necessitating tis- tions from metastatic disease that may be present on bone scin- sue sampling . Strengths and limitations of PET-CT in the diagnos- tigraphy; understand the presentation and differential diagnosis tic and staging of bone malignancy are also discussed . of benign bony lesions on bone scan, and understand findings on additional imaging modalities that provide successful diagno- Key Anatomic/Physiologic Issues and Imaging Findings/ sis of benign conditions . Techniques: This exhibit is a pictorial essay describing PET-CT patterns of inflammatory, infectious, traumatic, iatrogenic, and Key Anatomic/Physiologic Issues and Imaging Findings/ neoplastic musculoskeletal diseases . The presented pathologic Techniques: Radiopharmaceuticals in bone scintigraphy can elu- processes include arthroplasty wear-induced granuloma, bursitis, cidate more lesions and provide earlier diagnosis than conven- hemangioma, hibernoma, elastofibroma dorsi, aneurysmal bone tional radiography . We present several cases of primary benign cyst, oncogenic osteomalacia, schwannoma, sarcoidosis, pig- bony lesions demonstrating positive scintigraphic findings includ- mented villonodular synovitis, multiple myeloma, lymphoma, sar- ing a calvarial based hemangioma, nonossifying fibroma, cortical comas, and bone metastasis from different primary neoplasms . desmoids of the femur and a large sclerotic lesion thought to rep- Each entity will be reviewed and discussed in correlation/com- resent a metastasis demonstrating no increased uptake on bone parison with other imaging modalities . scintigraphy, the classic appearance of a bone island . Paget dis- ease characteristically displays increased uptake and expansion of Conclusion: After viewing this education exhibit, the participants the involved bone . Systemic diseases may also show increased will learn different features of benign and malignant muscu- activity, such as bone infarction in sickle cell anemia, cortical loskeletal diseases demonstrated by PET-CT, and understand uptake in hypertrophic pulmonary osteoarthropathy, and potential clinical applications, pitfalls and limitations of PET-CT in increased activity in sarcoidosis related arthropathy . Bone imaging musculoskeletal imaging . can be useful to evaluate patients with bone pain and equivocal radiographs, trauma that is difficult to evaluate on radiographs and subtle injuries such as insufficiency fractures and medial tibial

335 El e c t r o n i c Ex h i b i t s : Nuclear Medicine

E475. Qualitative Patterns of FDG Uptake Seen in the Brain cal context . The participant will also understand the limitations PET-CT Scan for Different Dementias (CME Credit Available) of FDG PET and compare it with ictal SPECT, another common Nasoodi, A.; Hughes, S. Belfast Trust, Belfast, United Kingdom functional imaging modality to understand which technique is Address correspondence to A. Nasoodi ([email protected]) preferred and when they provide complementary localizing infor- mation in different types of partial epilepsies . Background Information: Combined PET-CT with F-18 FDG is well established for routine oncological investigations but not for Key Anatomic/Physiologic Issues and Imaging Findings/ the assessment of early dementia . FDG PET is better than per- Techniques: Functional imaging with PET provides valuable fusion scintigraphy for the assessment of early dementia . The pat- information regarding the epileptogenic region in MRI negative terns of disease seen in early dementia assessment in FDG PET- intractable seizures . The most commonly used tracer is F-18 FDG, CT are sometimes different from those seen in perfusion studies . a glucose analogue, which provides functional information about uptake of glucose in the brain . Interictal FDG PET provides valua- Educational Goals/Teaching Points: The goals are for the par- ble localizing information, showing hypometabolism in the epi- ticipant in this activity to understand the difference in perfoming leptogenic region, in a variety of partial epilepsies, including tem- a PET-CT scan for dementia and oncology; to understand the pat- poral lobe epilepsy, extratemporal epilepsy, and some pediatric terns seen in the normal aging brain, and to understand the pat- epilepsy syndromes . There are limitations to this technique, such terns seen in the common and uncommon dementias . as overestimation of the epileptogenic focus . In some cases, ictal SPECT imaging can provide additional localizing information . In Key Anatomic/Physiologic Issues and Imaging Findings/ this exhibit, we will compare interictal PET, scalp and intracranial Techniques: We will show the indicators of a high quality FDG EEG, in multiple examples, and discuss the clinical impact of PET PET-CT brain scan . We will show normal brain patterns and pat- in each case . terns seen in the normal aging brain . We will show the patterns of disease seen in Alzheimer’s disease, frontotemporal dementia, Conclusion: The reader should understand the basics of PET Lewy body dementia, vascular dementia, mixed dementia and imaging in epilepsy, recognize the most common abnormal pat- Creutzfelt-Jacob disease . We will discuss the possible benefit of terns of glucose hypometabolism and become familiar with the the combined findings of the FDG distribution and the unen- optimal clinical use of FDG PET in presurgical localization of epi- hanced CT which can be obtained from the PET-CT scan . We will leptic foci . discuss the accuracy and reliability of this scanning technique in these different diseases . We will discuss the problems with using this technique in mild cognitive impairment (MCI) as opposed to E478. PET-CT in Head and Neck Cancer: Physiologic and early dementia . Pathologic Uptakes (CME Credit Available) Kanekar, S.; Goldenburg, D.; Otto, N. Penn State Milton S. Conclusion: The delegate should feel more confident in recog- Hershey Medical Center, Hershey, PA nizing the patterns of disease seen in dementia scanned with Address correspondence to S. Kanekar ([email protected]) FDG PET-CT and realize the advantages and shortcomings of this exciting technique . Background Information: CT and MRI are commonly used imaging modalities in evaluation of patients with head and neck cancer . Diagnosis or exclusion predominantly rely on nodal size, E476. PET Imaging in MRI Negative Epilepsy (CME Credit or contrast enhancement pattern which are nonspecific . Nodal Available) metastasis specificity is very low for the two routinely used Bahl, G.1; Juhasz ,C.2; Chugani, H.2 1. Wayne State Univ/Detroit modalities CT (39%) and MR (48%) . Diagnosis could be further Medical Center, Madison Heights, MI; 2. Wayne State University, challenging after radical surgery or radiation therapy where the Detroit, MI normal anatomical morphology gets distorted . Today combined Address correspondence to G. Bahl ([email protected]) PET-CT permits the synchronous images acquisition of anatomy and metabolic data . Background Information: Between 15-20% of epileptic sei- zures are intractable and may require surgical resection . Educational Goals/Teaching Points: The goals are to learn the Presurgical imaging is very important to identify the epileptogenic PET-CT appearances of various histiologic types of head and neck region to be removed for seizure-free surgical outcome . In cases tumors at different spaces of the neck, and to highlight the physi- where standard imaging fails to demonstrate an epileptogenic ologic uptake and mimics of the tumor . lesion, functional imaging with PET is a powerful tool for surgical planning . This exhibit will discuss the use of PET in intractable, Key Anatomic/Physiologic Issues and Imaging Findings/ MRI negative epilepsy . Techniques: We retrospectively assembled a cohort of 95 patients with surgically and/or biopsy proven cases of head and Educational Goals/Teaching Points: The exhibit will provide a neck cancer . We have divided this exhibit into two major catego- brief overview of the uses of other modalities, primarily MRI and ries . The first half of the exhibit illustrates and describes the vari- EEG, and limitations of these techniques in localizing the epilep- ous physiologic uptakes and their mimics while in the second togenic region and a brief introduction to PET imaging and F-18 half we discuss and describe the various pathologies . We illus- FDG as a tracer . After viewing this exhibit, the participant in this trate the variety of primary and secondary head and neck tumors activity will be be able to recognize the imaging findings of FDG involving the various spaces (oral, parapharyngeal, masticator, PET in common types of epilepsies . Multiple examples of typical parotid, carotid and base of the skull) . We also illustrate the limi- findings of interictal FDG PET will be displayed and put into clini- tations following postsurgical and postradiotherapy changes .

336 El e c t r o n i c Ex h i b i t s : Nuclear Medicine

Normal anatomical structures of the neck, such as glands, mus- Educational Goals/Teaching Points: The goals are to illustrate cle, fat, lymphoid tissue and mucosa can show increased uptake . the spectrum of artifacts in cardiac rest/stress studies using 99mTc Comprehensive knowledge of this physiologic uptake is impor- Sestamibi which mimic real ischemic disease and to present the tant to avoid false positives . information as a desktop algorithm for easy reference .

Conclusion: PET-CT has revolutionized the imaging of head and Key Anatomic/Physiologic Issues and Imaging Findings/ neck cancer . Techniques: We illustrate a spectrum of common and lesser known artifacts; explain their usual etiology and provide simple tools by which to differentiate real from artifactual findings of E479. PET-CT in Breast Cancer: Clinical Applications ischemia . We provide a ‘desktop algorithm’ that can be used by (CME Credit Available) trainees and non-nuclear specialists for guidance . Akin, E.; Katzen, J. George Washington University Hospital, Bethesda, MD Conclusion: Breast attenuation, adjacent hot or cold areas, Address correspondence to J. Katzen ([email protected]) reconstruction algorithm used, number of counts in image and attenuation correction with CT can all produce artifacts that Background Information: In conjunction with review of the lit- mimic real cardiac ischemia . Knowing how to differentiate these erature, we catalogued common PET-CT findings in detection, from real pathology can save unnecessary cardiac catherization staging, and recurrent breast cancer . and significant patient anxiety .

Educational Goals/Teaching Points: Interpretation of PET-CT requires knowledge of the staging scheme and understanding of E481. Malignant Peritoneal Mesothelioma: Characterization the pattern of spread of breast cancer . The audience will see by CT, PET and PET-CT (CME Credit Available) multiple examples of breast cancer in a variety of stages and Rasiej, M.1; Uldrick, T.2; Joffe, R.1; Austin, J.1; Taub, R.1; Ichise, become familiar with the PET-CT findings in these stages . This M.1 1. NewYork-Presbyterian Hospital Columbia University, New review also aims to demonstrate the added benefit and accuracy York, NY; 2. National Cancer Institute, Bethesda, MD of PET-CT in detection of recurrent and metastatic breast cancer Address correspondence to M. Rasiej ([email protected]) over other less sensitive imaging modalities . We will demonstrate common pitfalls in PET-CT interpretation of breast cancer . Background Information: Malignant peritoneal mesothelioma is a rare, aggressive tumor, which is known to show FDG uptake Key Anatomic/Physiologic Issues and Imaging Findings/ on PET and is commonly imaged with CT . The use of combined Techniques: This review, using specific case examples, emphasiz- PET-CT in the evaluation of malignant peritoneal mesothelioma es the superior accuracy of PET-CT in the detection of internal has not been extensively described . This exhibit will illustrate the mammary nodal metastases, as well as metastatic lesions to the imaging of malignant peritoneal mesothelioma, primarily focus- thoracic wall, and subtle lytic skeletal metastases not evident by ing on CT, PET and PET-CT with selected MRI correlations . conventional imaging modalities . In addition, imaging examples Implications of imaging for the diagnosis and assessment of are presented where PET-CT may be limited in detection of treatment of peritoneal mesothelioma, and also for future recurrence, so alternative imaging modalities can be selected, research directions will be discussed . such as bone scans in the setting of nonhypermetabolic sclerotic metastases . Educational Goals/Teaching Points: The exhibit will review the epidemiology, pathophysiology, histopathology and spectrum of Conclusion: PET-CT is the superior modality in detecting local CT, PET and PET-CT imaging characteristics of peritoneal mes- and regional nodal recurrence and distant metastases in breast othelioma, using representative cases; discuss the potential cancer . PET-CT should not replace histopathologic sampling for advantages of various cross-sectional imaging methods of perito- establishment of axillary nodal stage . PET-CT helps in deciding neal mesothelioma in the context of current multimodality which therapy regimen works . Additionally, PET-CT is able to help approach to treatment, and provide differential diagnosis for peri- determine when to discontinue a therapy regimen that the tumor toneal abnormalities on cross-sectional imaging . is unresponsive to . Ongoing development of new imaging agents will likely be important in tailoring therapy of breast cancer to the Key Anatomic/Physiologic Issues and Imaging Findings/ specific tumor type and behavior . Techniques: Malignant peritoneal mesothelioma is a rare, aggressive tumor, which demonstrates F-18 FDG uptake . FDG PET features include diffuse and nodular peritoneal uptake . CT fea- E480. Pitfalls of Nuclear Medicine Sestamibi Cardiac tures include several characteristic imaging findings, some also Imaging: A Pictorial Essay and Desktop Algorithm for shared by other peritoneal neoplasms . Cross-sectional anatomic Sorting Out Artifacts (CME Credit Available) and physiologic imaging techniques may provide complimentary Zentner, L.; Sivaratnam, D.; Better, N.; Lichtenstein, M. Royal information in the diagnosis and treatment of malignant perito- Melbourne Hospital, Parkville, Australia neal mesothelioma . Address correspondence to L. Zentner ([email protected]) Conclusion: F-18 FDG PET-CT is a valuable imaging modality in Background Information: Many artifacts have been identified in the characterization of malignant peritoneal mesothelioma in cardiac stress studies in nuclear medicine . When the artifact is in addition to traditional cross-sectional imaging methods . Further an arterial territory it often closely mimics ischemia . evaluation of test characteristics and imaging response criteria of PET-CT in the setting of peritoneal mesothelioma is warranted .

337 El e c t r o n i c Ex h i b i t s : Nuclear Medicine

E482. Frequency, Significance and Management of and the previously reported polonium poisoning case, radiologists “Incidentalomas” Found on PET-CT (CME Credit Available) and nuclear medicine professionals need to know how to help Scotti, S.2; Kassis, C.1; Staab, E.2 1. State University of New York assess and manage such situations . We may also have to bear at Buffalo, Buffalo, NY; 2. North Carolina Baptist Hospital, responsibility in our communities to protect other healthcare Winston Salem, NC workers, possibly exposed citizens, handle the press, and deal Address correspondence to S. Scotti ([email protected]) with law enforcement personnel . All are possibly involved in such circumstances . Having experienced several devastating hurricanes Background Information: The hybrid modality of PET-CT is an over the past few years, physicians along the Gulf have been exciting development in imaging, as it combines the advantages forced to learn and be skillful in disaster situations . of each respective modality — the highly sensitive detection of metabolic activity by PET scan and the accurate anatomic locali- Educational Goals/Teaching Points: We will review methods of zation of CT . However, while exciting, it is important to determine containment and assessment . Also we will review how to handle the incidence and significance of so-called ‘incidentalomas’, or the media appropriately, so as to inform and not cause any tumors (-omas) found by coincidence (incidental) without clini- panic . cal symptoms or suspicion, discovered serendipitously by PET-CT . Such findings occur with a small but significant frequency, and Key Anatomic/Physiologic Issues and Imaging Findings/ their incidence and significance vary by anatomic location . In one Techniques: Planning and discipline are key factors in handling study of thyroid incidentalomas the incidence was 4 .8% with unusual or crisis situations . To be effective a straightforward plan 3 8%. of patients having diffuse thyroid uptake and 1% having will help . focal thyroid uptake . 100% of the diffuse uptake cases were benign and 38% of the focal lesions were found to be malignant . Conclusion: As first responders in any “nuclear” event we must In another study of colorectal incidentalomas 2 .4% of patients be professional, helpful, and organized in our approach to any were found to have colorectal lesions satisfying strict criteria for unusual or potentially dangerous situation . If radiologists and an incidentaloma and 67% of these were found to be cancerous nuclear medicine professionals in the community do not provide or precancerous . We review similar data from the literature from such assistance, who will? multiple anatomic sites with examples . Being aware of this infor- mation should help with generating more accurate diagnoses and with improving patient care . E484. What to Do Before, During, and After a Catastrophe Involving Your Hospital’s Radiation Oncology and Nuclear Educational Goals/Teaching Points: We review the literature Medicine Departments: Special Considerations for and provide examples with PET-CT images of incidentalomas Protecting and Retrieving Nuclear Materials (CME Credit from multiple anatomic locations, including the adrenal gland, Available) bowel, brain, kidney, lung, ovary, pancreas, prostate, salivary Rodgers, B.1; Johnston, RN, MSN, M.2; Hafner, MHSA, RT, S.1; glands, thyroid, thymus, and several others . The goal is to edu- Reindl, MS, C.1; Brookes Ezell, M.1; Jacobs, A.1 1. Tulane cate the reader about the frequency, PET-CT appearance and sig- University, New Orleans, LA; 2. The Johns Hopkins Hospital, nificance of these incidentalomas by anatomic site so that these Baltimore, MD can be initially recognized and appropriate recommendations can Address correspondence to B. Rodgers ([email protected]) be made for the care of patients having these findings . Background Information: Nuclear materials can be found in Conclusion: Although incidentalomas on PET-CT are relatively most all radiation therapy and nuclear medicine departments . In infrequent, they occur frequently enough to be seen with some radiation therapy (and in some pathology departments), lethal regularity in a busy practice . It is therefore important to be famil- amounts are often present . Both current and spent (waste) iar with their incidence and significance by anatomic location, materials require supervised storage, use and disposal . They their PET-CT appearance and their management . A review of the require special handling . Multiple hurricanes, including Katrina, literature with example clinical cases with PET-CT images is one Rita, and more recently, Gustav, have taught us that updates to way of accomplishing this educational goal . Example cases are our disaster plan were required, especially pertaining to access provided for multiple anatomic locations, including the adrenal and the aftermath of flooding (cleanup) . gland, bowel, brain, kidney, lung, ovary, pancreas, prostate, sali- vary glands, thyroid, thymus, and several others, with recom- Educational Goals/Teaching Points: Tulane University Hospital mendations regarding management and care provided from the and Clinic had regulated nuclear imaging and therapeutic materi- literature . als in multiple locations and floors of our complex . Where flood- ing occurred during Hurricane Katrina on our first floor, issues of breakage or leaking–contamination–had to be addressed during E483. How Should You Deal With Unusual Radioactive our recovery and rebuilding phase . Adding to our problems, Exposure and Poisoning Situations (CME Credit Available) many of the recovery workers had little training or knowledge in Rodgers, B.1; Johnston, RN, MSN, M.2; Wasilewska, E.1; Palacios, handling nuclear materials . Other hospitals throughout the gulf E.1 1. Tulane University, New Orleans, LA; 2. The Johns Hopkins region have faced similar or worse issues in recent years . Some Hospital, Baltimore, MD problems could have been prevented with a better predisaster Address correspondence to B. Rodgers ([email protected]) plan . A highly coordinated approach with multiple areas of redundancy is required to best cope with such a crisis . Background Information: We face many threats to society, some are man made; some are not . Following in the wake of hur- ricane related damage in the Gulf region, threats of “dirty” bombs,

338 El e c t r o n i c Ex h i b i t s : Pediatrics

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: With an improved disaster plan, we should be bet- Pe d i a t r i c Im a g i n g ter able to survive the next potential disaster situation . Such plan- ning should be readily applicable to other potential disaster situ- E486. Benign Enlargement of the Subarachnoid Spaces in ations, for example tornado or earthquake damage . Infants: Truly Benign? (CME Credit Available) DiDomenico, P.; Palka, P. David Grant Medical Center, Travis AFB, Conclusion: By carefully planning what to do if the structural CA integrity of your building is compromised by a natural or man Address correspondence to P. DiDomenico (paul.didomenico1@ made event, potential serious consequences of unshielded nucle- travis.af.mil) ar materials can be avoided . Special consideration must be given to recovery workers who might be insufficiently trained in han- Background Information: Benign enlargement of the subarach- dling nuclear materials, especially for therapy sources and agents . noid spaces (BESS) in infants is often discovered incidentally or Planning is required to ensure that all nuclear materials remain when patients undergo neuroimaging in the workup of macro- safe and shielded during a catastrophe . Unsealed and unshielded cephaly . These patients are usually neurologically normal and sources can be life threatening otherwise . have no history of trauma . Studies have shown a correlation between this finding and an increased risk of subdural hemato- E485. Nuclear Regulatory Commission Knowledge: ABR Oral ma occurring either spontaneously or following minor, acciden- Exam Preparation Tutorial (CME Credit Available) tal trauma . Confusion may arise in such cases due to the associa- Amin, A.; Burns, N.; Colletti, P. University of Southern California, tion of subdural hematoma in infants with nonaccidental trauma . Los Angeles, CA A review of the literature cautions against this association, how- Address correspondence to P. Colletti ([email protected]) ever, in the absence of known high-specificity stigmata of nonac- cidental trauma . There is also a risk of communicating hydro- Background Information: In 2005, the Nuclear Regulatory cephalus which may develop in a low percentage of patients . We Commission (NRC) established guidelines for physicians who present cases illustrating these findings in patients who devel- would like to be designated with the status of auxiliary user . In oped normally without incident, and in patients who did have order to meet these criteria, residents in diagnostic radiology subdural hemorrhage although without concurrent evidence of must undergo more than 700 hours of education and training nonaccidental trauma . that includes a review of adequate handling of radionuclide sub- stances that are used in the imaging and treatment of patients . Educational Goals/Teaching Points: BESS may be benign but The written and oral radiology board examinations nuclear medi- also may confer increased risk of subdural hemorrhage and com- cine sections includes specific questions related to NRC regula- municating hydrocephalus . The finding may also be misinterpret- tions, including the safe handling of unsealed radiopharmaceuti- ed as representing chronic subdural hematomas . When subdural cals for diagnosis and therapy . hematoma is discovered in a patient with enlarged subarachnoid spaces, this finding is not specific for nonaccidental trauma . Educational Goals/Teaching Points: The purpose of this exhibit Treatment may be warranted if hydrocephalus develops . is to provide residents in radiology with a concise overview tuto- rial so that they can satisfactorily pass the nuclear medicine Key Anatomic/Physiologic Issues and Imaging Findings/ aspect of their radiology board examination as well as assist Techniques: Ultrasound, CT, and MRI imaging of the brain may them to practice in compliance with the NRC requirements . The demonstrate findings seen in BESS, as well as complications of presentation consists of radiation physics, monitoring personal subdural hematomas . A triad of symmetric extra-axial fluid overly- exposure, methods for proper decontamination, effective han- ing the cerebral hemispheres with extension into the interhemi- dling of radioactive materials and the maintenance of overall spheric fissure with mild compensatory dilatation of the anterior radiation safety while working in a nuclear medicine department . horns is most consistent with BESS and essentially excludes sub- The tutorial will contain exhibits detailing how a radionuclide spill dural hematomas . should be properly assessed and decontaminated as well as cases and questions that will test and provide adequate explana- Conclusion: BESS in infants may be encountered in routine tions for maintaining safety in the nuclear medicine department . practice by general, pediatric, and neuroradiologists . While this finding is benign in many cases, there is an increased risk of sub- Key Anatomic/Physiologic Issues and Imaging Findings/ dural hemorrhage either spontaneously or following minor trau- Techniques: The exhibit will include information on safe acqui- ma . A low percentage of patients may develop communicating sition, storage, and administration of radiopharmaceuticals; hydrocephalus, which may warrant treatment . Radiologists may response to radioactive spills; appropriate handling of radioactive better serve patients and referring clinicians through the recogni- waste; quality assurance for radiopharmaceuticals, and quality tion that the presence of subdural hematoma in patients with assurance for nuclear medicine equipment . BESS is not specific for nonaccidental trauma and should be cor- related with the presence or absence of higher-specificity lesions Conclusion: This exhibit will provide residents in diagnostic radi- for this diagnosis . ology with an educational program in nuclear medicine so that residents will be able to meet the guidelines set forth by the Nuclear Regulatory Commission and American Board of Radiology .

339 El e c t r o n i c Ex h i b i t s : Pediatrics

E487. Shedding Light on Echogenic Neonatal Brain Lesions requires no contrast or sedation . Cranial sonography is an indis- (CME Credit Available) pensable tool for the diagnosis, followup, and prediction of out- Wolfman, D.; Khianey, A.; Allison, S. Georgetown University come in infants with subependymal, intraventricular, and paren- Hospital, Washington, DC chymal hemorrhage . Address correspondence to D. Wolfman ([email protected])

Background Information: The purpose of this presentation is to E489. Shaking Out the Causes of Pediatric Seizures by review the differential diagnosis of an echogenic brain lesion on Imaging (CME Credit Available) neonatal brain ultrasound; review the ways to differentiate Taheri, M.1; Chung, J.1; Richardson, R.1,2; Patterson, K.2; Ishak, between the different echogenic brain lesions on neonatal brain G.1,2 1. University of Washington, Seattle, WA; 2. Children’s ultrasound, and discuss pertinent imaging findings of the differ- Hospital and Medical Center, Seattle, WA ent echogenic brain lesions on neonatal brain ultrasound . Address correspondence to M. Taheri ([email protected])

Educational Goals/Teaching Points: The goals of this presenta- Background Information: The goals are to review the role of tion include reviewing the optimal technique to perform neonatal imaging in the work-up of children with seizures, as only a small brain ultrasound; reviewing the differential diagnosis of an echo- fraction of children with seizures require imaging; to discuss the genic brain lesion on neonatal brain ultrasound, including imag- spectrum of imaging findings associated with pediatric seizures, ing findings for each lesion, and reviewing ways to distinguish and to provide examples of pathologic correlates with images of between echogenic brain lesions on neonatal brain ultrasound, selected cases . including pitfalls and mimics . Educational Goals/Teaching Points: The exhibit will include Key Anatomic/Physiologic Issues and Imaging Findings/ guidelines on how to approach a child with seizures; sample Techniques: The ability to accurately diagnose echogenic brain cases along with pathological appearances of common tumors, lesions on neonatal ultrasound significantly impacts patient care . cortical dysplasia, and sclerosis/gliosis with or without vascular This review will help the physician better understand the differ- causes associated with pediatric seizures, and sample cases of ential diagnosis of echogenic brain lesions on ultrasound, includ- other potential etiologies of pediatric seizures such as infections, ing its limitations . developmental malformations, and dysmyelinating disorders .

Conclusion: After viewing the exhibit the physician should be Key Anatomic/Physiologic Issues and Imaging Findings/ able to discuss the differential diagnosis of an echogenic lesion Techniques: The exhibit will discuss the CT and/or MR imaging on neonatal brain ultrasound; describe the imaging findings of findings that can assist in formulating a differential diagnosis in the different echogenic lesions on neonatal brain ultrasound, and the setting of pediatric seizures; introduce the complementary role describe imaging pitfalls and mimics of echogenic lesions on of spectroscopy in diagnosis of specific dysmyelinating diseases, neonatal brain ultrasound . and discuss the microscopic appearance of common tumors, cor- tical dysplasia, and sclerosis/gliosis that assist in their diagnosis .

E488. Sonography of the Infant Brain: Anatomy, Conclusion: Many children with seizures do not require imaging . Hemorrhage, Hypoxic/Ischemic Disease (CME Credit Various cerebral abnormalities can cause seizures; each has dis- Available) tinctive imaging characterisitics . Pathological correlation helps Rosenberg, H.; Mehta, A.; Chaudhry, H. Mount Sinai Medical confirm the diagnosis in a fraction of the cases . Center, New York, NY Address correspondence to H. Rosenberg (henrietta.rosenberg@ mountsinai.org) E490. An Array of Common Pediatric Breast Abnormalities (CME Credit Available) Background Information: The advent of high-resolution real- Kim, A.; Woodfield, C.; Donegan, L. The Warren Alpert Medical time sonography in the 1980s revolutionized the imaging School of Brown University/Rhode Island Hospital, Providence, RI approach to the infant brain . This noninvasive, nonionizing imag- Address correspondence to A. Kim ([email protected]) ing modality with portable and repeatable capabilities is not only cost effective but is readily available and reliable for the evalua- Background Information: Most palpable masses in the pediat- tion and follow-up of intracranial hemorrhage in infants . This ric and adolescent patients are benign . However, due to the education exhibit reviews the ultrasound appearance of brain increased awareness of breast cancer, a breast lump in a child or hemorrhage and its sequelae in premature and full-term infants . adolescent may alarm both the parent and the child . Physical examination should be the initial examination, followed by an Educational Goals/Teaching Points: The goal of this exhibit is ultrasound examination of the palpable mass . It is important to to provide the reader with information regarding the risk factors recognize both benign and malignant findings to aid in patient for and the sonographic findings of intracranial hemorrhage in management . premature and full-term infants, to present the classification of intracranial hemorrhage in the premature infant and to contrast Educational Goals/Teaching Points: The goals are to review the patterns seen in the full-term infant, as well as to elaborate the stages of normal breast development; review the different on the anticipated sequelae of these insults to the infant brain . entities that manifest as palpable breast masses in the pediatric and adolescent patient, and recognize the sonographic imaging Conclusion: High-resolution ultrasound is a sensitive, accurate, features that distinguish benign from malignant lesions in pediat- noninvasive, nonionizing portable imaging modality which ric and adolescent patients .

340 El e c t r o n i c Ex h i b i t s : Pediatrics

Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: Recognition of coronary artery anomalies is essen- Techniques: The exhibit will review normal breast development; tial in the management of congenital heart diseases . 3D naviga- common pediatric breast abnormalities, including gynecomastia, tor gated MRI is a very effective sequence used in assessment of cyst, fibroadenoma, lymph node, infection and malignancy, and coronary artery anomalies . sonographic imaging to help distinguish benign from malignant lesions in the pediatric and adolescent patient population . E492. Pediatric Gastrointestinal Review (CME Credit Conclusion: Understanding the normal stages of breast develop- Available) ment is important to prevent cases of iatrogenic . The Vinocur, D.; Schenider, S.; Reeves-Garcia, J.; Restrepo, R. Miami vast majority of palpable masses in the pediatric and adolescent Children’s Hospital, Miami, FL patient population are benign . Ultrasound examination is the Address correspondence to D. Vinocur ([email protected]) study of choice when evaluating a palpable mass in the pediatric population . Understanding and recognizing the sonographic Background Information: Pediatric gastrointestinal (GI) disor- imaging features of benign vs . malignant lesions aids in further ders are very common . These can be found incidentally or as the management . first manifestation or a complication of intrinsic gastrointestinal pathology . On this exhibit we depict multiple examples of these entities from the esophagus to the rectum using different imag- E491. MRI in Evaluation of Coronary Artery Anomalies in ing modalities such as CT scans, ultrasound and fluoroscopic Congenital Heart Diseases: A Pictorial Review (CME Credit examinations and the corresponding intraoperative/endoscopic Available) findings . Rajiah, P. Cleveland Clinic Foundation , Cleveland, OH Address correspondence to P. Rajiah ([email protected]) Educational Goals/Teaching Points: This exhibit will allow the audience to identify the different modalities for the specific GI Background Information: Congenital heart diseases are fre- abnormality in the pediatric population . High yield pearls will be quently associated with variations in coronary anatomy . Due to presented for each entity emphasizing its diagnostic role . considerable heterogeneity of coronary vasculature, it is often unclear what is normal, variant, abnormal, atypical, accessory or Key Anatomic/Physiologic Issues and Imaging Findings/ aberrant . Anomalous origin or course can result in sudden cardi- Techniques: A systematic multimodality gallery of images are ac death . Knowledge of the anomaly is vital in planning for sur- presented depicting the different array of disorders such as con- geries . MRI plays a vital role in assessing these anomalies . genital abnormities, foreign bodies, polyposis syndromes, intesti- nal obstructions, etc . Image modalities include plain radiographs, Educational Goals/Teaching Points: This pictorial review illus- fluoroscopy, CT, ultrasound and correlating intraoperative/endos- trates the various coronary artery variations and anomalies asso- copy imaging . ciated with congenital heart disease . Recognition of coronary var- iations is essential in preventing sudden cardiac death and for Conclusion: Pediatric gastrointestinal abnormalities are very surgical planning of congenital heart diseases . In Tetralogy of common but diverse . A systematic, multimodality approach Fallot, the left coronary artery arises more posterior due to a would allow us to achieve diagnosis while minimizing imaging more rightward position of the aorta . In transposition of great and therefore, radiation dose . arteries (TGA) the coronary arteries arise from nonfacing sinuses .

Key Anatomic/Physiologic Issues and Imaging Findings/ E493. Gender Differences in Urinary Tract Morphology in the Techniques: Normally the right and left coronary arteries arises Fetus perpendicular to the aortic sinus, from nonfacing sinuses . Rasalkar, D.; Chu, W. Chinese University of Hong Kong, New Anomalies can be related to origin, course, termination or intrin- Territories, Hong Kong sic coronary arterial anatomy . There is a wide spectrum of anom- Address correspondence to D. Rasalkar ([email protected]) alies . In TGA, the coronary arteries arise from nonfacing sinuses and there is extreme variation in course (high take off, paracom- Objective: The objective was to study renal pelvic size and uri- missural orifice, or tangential origin) . Arterial repair is contraindi- nary bladder volume in male and female fetuses between 36-38 cated in those patients with intramural course of coronary arter- weeks of gestational age using ultrasound . ies . In Tetralogy of Fallot, there is often an anomaly, the usual one being the left anterior descending arising from the right cor- Materials and Methods: A total of 414 normal singleton preg- onary artery, which courses across the pulmonary outflow tract . nancies between 36-38 weeks of gestational age were included . The left artery is more posterior than normal, due to more right- In each fetus, anteroposterior (AP) diameter of the fetal renal ward position of the aorta . Conus branch may be large and result pelvis was measured, and urinary bladder volume (BV) was cal- in an alteration of the surgical approach . In pulmonary atresia, culated using the ovoid volume formula . abnormal persistent right ventricular coronary sinusoidal connec- tions are noted . MRI is very useful in evaluation of coronary Results: Male fetuses were found to have greater AP diameter of artery anomalies in congenital heart diseases . Advantages of MRI renal pelvis than females . The mean AP diameter of renal pelvis are its multiplanar capabilities and absence of ionizing radiation in male fetuses was 2 69. ± 0 93. mm while in females it was associated with CT . Free breathing technique is adopted with 2 .46 ± 0 87. mm (p<0 05,. independent sample T test) . Female navigator gating and T2 prep pulse, with 3D steady state free fetuses were found to have a greater BV than male . The mean precession acquisition . BV in male fetuses was 13 .93 ± 8 .43 cm3 while in females it was 17 .22 ± 10 .22 cm3 (p<0 .05, independent sample T test) .

341 El e c t r o n i c Ex h i b i t s : Pediatrics

Conclusion: Gender difference in urinary tract morphology associations which are characteristic to specific renal tumors . implies that the respective development is probably different Imaging findings will be correlated with gross and microscopic between male and female fetuses . The above difference might pathological specimens . account for a higher incidence of urinary tract infection and vesi- coureteric reflux in boys during the neonatal period . Educational Goals/Teaching Points: The presentation will be in didactic format covering CT, MR, and US findings of various com- mon and rare pediatric renal tumors . Cases will include Wilms E495. Pelvic Neuroblastoma: Radiologic-Pathologic tumor-favorable and unfavorable histology, and bilateral tumors, Correlation lymphoma, medullary carcinoma, rhabdoid tumor, primitive neur- Srinivasan, A.; Weiss, S. SUNY Upstate University Hospital, oectodermal tumor (PNET), nephroblastomatosis, and angiomy- Syracuse, NY olipoma . The exhibit will include pathological correlations, and Address correspondence to A. Srinivasan ([email protected]) will discuss clinical associations, differential diagnoses .

Background Information: The pelvis is an unusual primary site Key Anatomic/Physiologic Issues and Imaging Findings/ for neuroblastoma, accounting for only 2% to 5% of all neurob- Techniques: The differential diagnosis and clinical presentations lastomas . In this educational exhibit, we will discuss the clinical will be reviewed for the variety of pediatric renal tumors, with an presentation of pelvic neuroblastoma, advantages and disadvan- emphasis on the imaging findings . tages of different diagnostic modalities, imaging features in ultrasound, CT and MRI, differential diagnosis for presacral mass- Conclusion: Upon completion of the presentation, the viewer es in pediatric population, and significance of prompt diagnosis should have an understanding of the different imaging features, in surgical and treatment planning . clinical associations, and current opinions on the imaging follow- up for various renal tumors affecting the pediatric population . Educational Goals/Teaching Points: Neuroblastoma can origi- The reader should also be able to recognize both common as nate anywhere along the sympathetic chain from neck to pelvis . well as rare pediatric renal tumors . Prognosis of the neuroblastoma depends on the age of diagnosis and tumor site . After viewing the exhibit, the participant will understand the risks and benefits of ultrasound, CT and MRI in E498. Demystifying Skeletal Dysplasias: Radiologic Findings diagnosis and will know ultrasound, CT and MRI imaging features Involving the Spine (CME Credit Available) commonly seen in pelvic neuroblastoma and differential diagno- Parnell, S.1,2; Chew, F.2 1. Seattle Childrens Hospital, Seattle, WA; sis for presacral masses in pediatric patients . 2. University of Washington Medical Center, Seattle, WA Address correspondence to S. Parnell (shawn.parnell@seattlechil- Key Anatomic/Physiologic Issues and Imaging Findings/ drens.org) Techniques: Ultrasound is used as the initial imaging modality for detecting pelvic neuroblastoma . In addition, CT or MRI is Background Information: Skeletal dysplasias are a heterogene- needed for characterizing the origin, invasion and surgical plan- ous group of more than 250 disorders characterized by abnormal ning . Moreover, there are added benefits in performing MR over bone growth . Skeletal dysplasias are difficult to describe and cat- CT, such as preventing risks from ionizing radiation in pediatric egorize, but with a properly organized thought process and the patients, improved soft tissue contrast resolution and multiplanar use of standard nomenclature, the radiologist can make sense of capabilities . In pelvic neuroblastomas, MR is also extremely use- these challenging cases . More effective consultations with ortho- ful for detecting extension of tumor into the spinal pedic surgeons and geneticists regarding patients with skeletal canal . However, definitive diagnosis of pelvic neuroblastoma dysplasias may in turn lead to targeted genetic testing, specific requires tissue biopsy . diagnoses, and optimal management . By focusing on specific body regions and providing an organizational structure, we seek Conclusion: Although the incidence of pelvic neuroblastoma is to demystify skeletal dysplasias for the general radiologist . rare, a prompt diagnosis is crucial for the the tumor site and age of diagnosis . Therefore, it is vital that we understand the risks Educational Goals/Teaching Points: After the completion of and benefits of different modalities and their imaging features, this activity, the participant will be able to recognize the variety of and ultimately the need for pathological diagnosis for timely spinal abnormalities seen with skeletal dysplasias and use a treatment . standard nomenclature to describe them; utilize an organized approach to evaluate the spine in cases of suspected skeletal dysplasias; discuss typical patterns of clinical and imaging find- E496. Pediatric Renal Tumors: CT, MR, and Clinical and ings associated with several of the more common skeletal dys- Pathological Correlation (CME Credit Available) plasias that have characteristic spine abnormalities, and list sever- Hines, J.1; Bittman, M.1; Choi-Rosen, J.1; Barlev, D.2; Katz, D.2; al categories of skeletal dysplasias that have spine involvement Price, A.3; Abramson, S.3 1. Long Island Jewish Medical Center, as a major or solitary component . New Hyde Park, NY; 2. Winthrop-University Hospital, Mineola , NY; 3. Memorial Sloan Kettering Cancer Center, New York, NY Key Anatomic/Physiologic Issues and Imaging Findings/ Address correspondence to D. Katz ([email protected]) Techniques: The appearance and nomenclature of imaging find- ings in the spine that are commonly seen with skeletal dysplasias Background Information: The goals are to provide an educa- will be reviewed, including platyspondyly, clefting, scalloping, tional review of both common and rare pediatric renal neo- beaking, interpediculate narrowing, spinal stenosis, scoliosis, gib- plasms and to detail and discuss imaging findings using CT, MR, bus deformity, and cervical kyphosis . Skeletal dysplasias with char- and ultrasound (US) . The discussion will include pertinent clinical acteristic spine features, to include the spondyloepiphyseal and

342 El e c t r o n i c Ex h i b i t s : Pediatrics spondylometaphyseal dysplasias, achondroplasia, pseudoachon- osseous inflammation in young persons . There is a predilection droplasia, atelosteogenesis, brachyolmia, diastrophic dysplasia, for involvement of the metaphyses of long bones including the and dysostosis multiplex will be demonstrated and correlated pelvic girdle, clavicle and spine although no classic imaging fea- with imaging findings, clinical presentation, and genetic attributes . tures have been described . Although CRMO has been a recog- nized entity for nearly four decades, prospective imaging diagno- Conclusion: This computer-based educational exhibit reviews the sis remains challenging . spine abnormalities seen in skeletal dysplasias on radiography and cross-sectional imaging, and explains and demonstrates the Educational Goals/Teaching Points: The goals are to create use of standard nomenclature to describe them . These findings awareness regarding CRMO as a distinct though elusive patho- are then correlated with clinical information and synthesized into logic entity in the pediatric and young adult population; demon- diagnostic categories . Case examples of several common skeletal strate multimodality imaging features; review common and unu- dysplasias will be reviewed with emphasis on characteristic spine sual locations involved, and provide an appropriate prospective involvement, patterns of other related radiographic findings, asso- differential diagnosis . ciated clinical findings, and underlying genetic mutations . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Using illustrative cases from our radiology and E499. Osseous Lesions Mimicking Osteochondromas pathology data base, a multidisciplinary and multimodality Robinette, A.; Rivera, R.; Richardson, R. St. Joseph’s Medical approach will be used to illustrate the usual imaging features of Center, Scottsdale, AZ CRMO . Plain radiographs, CT, MR and nuclear medicine bone Address correspondence to A. Robinette (alisonrobinette@yahoo. scan imaging features in typical and atypical locations will be com) presented . The presentation will incorporate clinical course and differential diagnosis of each of the cases . Atypical features that Background Information: An osteochondroma is a cartilage tend to confound early and prompt diagnosis will be highlighted covered bony exostosis that arises from the surface of a bone, and discussed . Pathologic features that facilitate the diagnosis and is the most common bone tumor in children . There are mul- will be reviewed . The prognosis and management of the entity tiple lesions that can mimic osteochondromas . Knowledge of will also be discussed . these lesions and familiarity with their attributes enables one to develop an appropriate differential diagnosis when such a lesion Conclusion: The absence of pathognomonic imaging fea- is encountered radiographically . tures and variable disease course confound the clinical scenario of CRMO . The absence of an infective organism, plethora of plas- Educational Goals/Teaching Points: The goal is to familiarize ma cells, lymphocytes and chronic inflammatory cells on tissue the audience with the various types of lesions that can mimic biopsy remain essential for the diagnosis . osteochondromas .

Key Anatomic/Physiologic Issues and Imaging Findings/ E501. MRI of Pediatric Body Masses Simulating Techniques: Plain film, CT, and MR images will be presented Malignancies (CME Credit Available) demonstrating osseous lesions that mimic osteochondromas, Kramer, L. University of Texas Health Science Center at Houston, in five different categories, including post-traumatic (myositis Houston, TX ossificans, periosteal reaction, Osgood Schlatter’s, bizarre paro- Address correspondence to L. Kramer ([email protected]) steal osteochondromatous proliferation, subungual exostosis); normal variants/developmental (accessory humeral condyle, bifid Background Information: The purpose of this exhibit is to distal phalanx, diastamatomyelia, dysplasia epiphysealis hemime- review a gamut of non-neoplastic body masses that can present lia, supracondylar process of the humerus, spurring at the growth at birth or later in childhood . In some cases these masses can plate); metabolic bone disease (scurvy, pseudohypoparathy- have characteristic features on MRI that allow differentiation from roidism, pseudopseudohypoparathyroidism); physiologic (hemo- malignancies and require no further treatment or intervention . philia, sickle cell disease, tumoral calcinosis), and neoplasm (osteosarcoma, Ewing’s sarcoma, metastases) . Educational Goals/Teaching Points: The educational goal is to describe the MRI findings of various categories of pediatric mass- Conclusion: There are several osseous lesions that mimic an es in the newborn and childhood time periods which can simu- osteochondroma, and these should be considered in the differ- late malignancies . The exhibit focuses on the following: newborn ential diagnosis when such a lesion is encountered . (hormonal, developmental, stress induced); childhood (hormo- nal, developmental stress induced, acquired), and unusual child- hood masses . E500. Chronic Recurrent Multifocal Osteomyelitis: Imaging Features That Facilitate and Confound Prompt Diagnosis Key Anatomic/Physiologic Issues and Imaging Findings/ Vyas, R.; Siripun, L.; Seo, G.; Meyers, S.; Monu, J. University of Techniques: The primary imaging technique described is conven- Rochester Medical Centre, NY, Rochester, NY tional MRI and includes imaging of the chest, abdomen, pelvis Address correspondence to R. Vyas (rajashree_vyas@urmc. and extremities . rochester.edu) Conclusion: Children with a congenital or a new onset mass Background Information: Chronic recurrent multifocal osteo- lesion generate concern for possible malignant pathology . There myelitis (CRMO) is a recognized rare inflammatory condition of are however, many nonneoplastic masses which are the result of uncertain etiology . It is a cause of the most severe form of sterile a developmental anomaly, normal or abnormal hormonal stimu-

343 El e c t r o n i c Ex h i b i t s : Pediatrics lation, repetitive stress or are acquired . Some of these entities Key Anatomic/Physiologic Issues and Imaging Findings/ can have characteristic features on MRI, which should provide Techniques: With multiple imaging techniques (X-ray, helical CT reassurance of the likelihood of a benign process and will be and MRI), identification of pediatric nonaccidental trauma and reviewed in detail in this exhibit . differentiation from mimics is often possible .

Conclusion: Clinical information, knowledge of normal pediatric E502. A Simple Approach to Tubes and Lines on Neonatal variants, and imaging characteristics of nonaccidental trauma are Radiographs (CME Credit Available) essential for appropriate radiological evaluation as part of a Vyas, R. University of Rochester Medical Center, NY, Rochester, NY multidisciplinary approach . Address correspondence to R. Vyas (rajashree_vyas@urmc. rochester.edu) E504. Clinical Experience with Gadobenate Dimeglumine for Background Information: Evaluation of commonly used tubes Contrast-Enhanced MRI in Children and lines in neonates can be confusing to the novice radiologist . Colosimo, C.1; Pasowicz, M.2; Demaerel, P.3; Tortori-Donati, P.4; Unfamiliarity with appropriate positioning can hamper accurate Gao, P.5 1. University of the Sacred Heart, Rome, Italy; 2. Krakow assessment in even experienced radiologists who do not primari- Hospital John Paul II, Krakow, Poland; 3. University Hospital K.U. ly interpret neonatal radiographs . Since inadvertently malposi- Leuven, Leuven, Belgium; 4. Institute G. Gaslini, Genoa, Italy; 5. tioned tubes and lines can have disastrous consequences if Beijing Tian Tan Hospital, Beijing, China unrecognized, this exhibit aims to create awareness of the appro- Address correspondence to C. Colosimo ([email protected]) priate placement of tubes and lines commonly used in the neo- natal intensive care unit (NICU) ultimately contributing to Objective: The objective was to summarize safety and efficacy of enhanced patient care . the higher-relaxivity gadolinium (Gd) agent gadobenate dimeglu- mine (Gd-BOPTA) in children . Educational Goals/Teaching Points: The goals of the exhibit are to review commonly used tubes and lines in the NICU; dis- Materials and Methods: Safety was evaluated in 151 subjects cuss appropriate positioning of tubes and lines on neonatal radi- receiving Gd-BOPTA at a dose of 0 .1 mmol/kg, 85 of whom par- ographs; demonstrate examples of malpositioning with complica- ticipated in a comparison study in which 89 subjects received tions, and increase diagnostic interpretation confidence in the equimolar gadopentetate dimeglumine (Gd-DTPA) . Image quality novice/general radiologist . was evaluated in 70 patients receiving Gd-BOPTA, including 29 children with enhancing lesion compared with 34 children receiv- Key Anatomic/Physiologic Issues and Imaging Findings/ ing Gd-DTPA . Serial 24 hour blood and urine collections were Techniques: Neonatal chest and abdominal radiographs with used to determine Gd-BOPTA pharmacokinetics (PK) in 25 sonographic assessment of some complications will be present- healthy children . ed . A review of umbilical vascular anatomy will be included . Results: Eighteen of 151 patients (11 6%). experienced adverse Conclusion: A comprehensive understanding of neonatal anato- events (AE), most of which were mild . The most commonly my, commonly used neonatal tubes and lines along with knowl- reported AE were fever and headache . Modest increases and edge of appropriate positioning is important in the assessment of decreases in vital signs were recorded, but no significant changes neonatal radiographs . Accurate assessment will enhance patient in laboratory parameters or ECGs were observed . In the compari- care in the precarious neonatal period and pre-empt preventable son study, AE rates were similar after Gd-BOPTA (11 subjects, complications . 13%) and Gd-DTPA (13 subjects, 14%), p=0 .75 . PK data best fit a two-compartment model, with >90% recovery in urine at 24 hours . In children with enhancing lesions, contrast enhancement E503. Pediatric Nonaccidental Trauma (CME Credit was considered good to excellent in all subjects . Gd-BOPTA Available) resulted in improved definition of disease extent, lesion border Goud, A.1; Golshan, M.; Gibbs, L.; Panigrahy, A.2 1. University of delineation, and visualization of lesion internal morphology . In California Irvine Medical Center, Orange, CA; 2. Children’s the comparison study, postdose changes in lesion visualization Hospital Los Angeles, Los Angeles, CA were significantly greater for Gd-BOPTA than Gd-DTPA at the Address correspondence to A. Goud ([email protected]) lesion (p=0 .011) and patient level (p=0 .008) .

Background Information: Radiologic evaluation of nonacciden- Conclusion: Gd-BOPTA is well tolerated, with safety and pharma- tal trauma is an integral part of a multidisciplinary approach to cokinetics comparable to other Gd agents . Compared to ensure accurate and timely diagnoses in the pediatric population . Gd-DTPA, Gd-BOPTA performed significantly better for visualiza- tion of central nervous system tumors in pediatric patients . Educational Goals/Teaching Points: Appropriate imaging stud- ies, classic radiographic findings of pediatric nonaccidental trau- ma, and identification of possible mimics will be illustrated and discussed . The multidisciplinary approach to the diagnosis of nonaccidental trauma will also be addressed .

344 El e c t r o n i c Ex h i b i t s : Interventional

Educational Goals/Teaching Points: We review the various Va s c u l a r /In t e r v e n t i o n a l manifestations of treatment failure and complications that are encountered on a busy hepatic RFA service based on our experi- E505. TIPS for You: A Comprehensive Review of the ence of over 700 hepatic ablations . In this review, we suggest Anatomical and Pathological Variants Seen in Transjugular ways to anticipate an increased risk of these adverse outcomes Intrehepatic Portosystemic Shunt Placement based on clinical presentation and cross-sectional imaging . We Lee, E.; Choi, D.; Chen, C.; Douek, M.; Loh, C.; Kee, S. University will then demonstrate various treatment strategies and approach- of California Los Angeles Medical Center, Los Angeles, CA es that we have utilized to help reduce these outcomes, and Address correspondence to E. Lee ([email protected]) improve the efficacy, safety, and therapeutic profile of hepatic RFA . Additionally, we discuss the judicious use of complimentary Background Information: Recently transjugular intrahepatic image guidance strategies such as CT fluoroscopy, ultrasound, portosystemic shunts (TIPS) have become an effective treatment and newer fused image guidance techniques . option for relief of portal hypertension (PHTN) and other more lethal complications associated with PHTN . During the TIPS pro- Key Anatomic/Physiologic Issues and Imaging Findings/ cedure, identification of portal and hepatic anatomy can be Techniques: Complications of hepatic RFA can be both focal and extremely challenging due to the presence of normal variants, systemic and may result from either thermal or nonthermal inju- congenital variants and acquired collateralization of vessels . In ry . The imaging manifestations of specific complications such as this comprehensive pictorial review, we will demonstrate various vascular injury, hemorrhage, infection, biloma, pneumothorax, anatomical vascular variants seen in TIPS with different imaging tumor seeding, and visceral thermal injury are reviewed and modalities including angiography, CT, CT angiography, MRI, MR strategies which may be used to reduce these are discussed . angiography and ultrasound . Approaches to reducing nontarget thermal injury, such as hydro- dissection, pharmacological techniques, and careful patient posi- Educational Goals/Teaching Points: The goals are to provide a tioning are illustrated . Approaches to reducing local treatment comprehensive review of the anatomical vascular variants failure by increasing treatment area size utilizing strategies such encountered in TIPS procedures, and to provide a pictorial review as clustered electrodes, switchbox techniques, and multiple over- of various radiological and pathological images of liver diseases lapping treatment zones are reviewed . More experimental tech- requiring TIPS . niques such as the Pringle maneuver, pharmacological and radio- therapeutic adjuvants are presented . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The exhibit will include a background review on Conclusion: In this review we present strategies to correctly TIPS; pictorial review and presentation of various anatomical vas- identify patients at increased risk for hepatic RFA treatment fail- cular variants seen in TIPS procedures; a pictorial review of vari- ure or complication, and we present various approaches and ous radiological presentations of liver diseases requiring TIPS methods we have utilized to reduce these adverse outcomes . placement, and a pictorial review of various pathological images of liver diseases requiring TIPS placement . E507. Pictorial Review of the Mesenteric Arterial Collateral Conclusion: After reviewing this educational exhibit, radiologists Circulation Utilizing Angiography should be able to recognize the different imaging presentations Demetri-Lewis, A.; Maroney, T.; Goldmakher, G. Hahnemann of liver diseases for which TIPS placement is indicated; recognize University Hospital, Philadelphia, PA the different anatomical vascular variants often seen in TIPS pro- Address correspondence to A. Demetri-Lewis ([email protected]. cedures, and gain an in-depth knowledge on TIPS that will allow edu) for more efficient communication between clinicians leading to optimal patient management . Background Information: The intestinal tract has an extensive collateral network that either prevents or limits bowel ischemia when central arteries become obstructed . The major mesenteric E506. Hepatic Radiofrequency Ablation: Strategies to arterial collateral pathways include the intraceliac branches, the Anticipate and Reduce Complications and Treatment celiac and superior mesenteric arteries (SMA), the superior and Failures (CME Credit Available) inferior mesenteric arteries (IMA), and the inferior mesenteric Midkiff, B.; Brennan, D.; Goldberg, S. Beth Israel Deaconess and iliac arteries . This collateral circulation is important clinically Medical Center, Boston, MA not only in the setting of mesenteric ischemia, but familiarity Address correspondence to B. Midkiff ([email protected]) with the various mesenteric collaterals is very important to the interventionalist when treating gastrointestinal bleeding . The pur- Background Information: Interventional oncology is a rapidly pose of this exhibit is to provide a pictorial review of the major diversifying field, and hepatic radiofrequency ablation (RFA) has mesenteric collateral pathways, as well as anatomic variants, played an increasing role in the treatment of primary and sec- including a profunda femoral artery collateral supply to the SMA . ondary hepatic neoplasms . Treatment failures and complications in hepatic RFA have been documented in a largely anecdotal Educational Goals/Teaching Points: The goal of this exhibit is fashion . With increasing experience, it has become more evident to review the major mesenteric collateral pathways encountered that certain technical factors, disease sites, and ablation practices on angiography . Multiple anatomic variants will also be illustrated . may predispose a patient to a greater risk of treatment failure or complication . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Typically, the celiac artery supplies the foregut, hepatobiliary system, and spleen . The SMA supplies the midgut

345 El e c t r o n i c Ex h i b i t s : Interventional

(ie, small intestine and proximal mid colon) . The IMA supplies E509. The Abnormal Abdominal Aorta: Primary Aortic or the hindgut (ie, distal colon and rectum) . This exhibit is a pictori- Periaortic Disease? al review of the mesenteric collateral pathways, including the Sekhar, A.; Lee, K.; Pedrosa, I. Beth Israel Deaconess Medical gastric arcade, gastroepiploic arcade, arc of Barkow, pancreatic Center, Boston, MA arcade, arc of Buhler, marginal artery of Drummond, arc of Address correspondence to A. Sekhar ([email protected]. Riolan, and the rectal (hemorrhoidal) arcade . Multiple anatomic edu) variants will also be illustrated . Background Information: Abdominal aortic diseases can be life Conclusion: Familiarity of the mesenteric arterial collateral path- threatening and require timely and accurate diagnosis . An abnor- ways is essential to the angiographer in the setting of bowel mal abdominal aorta on imaging studies, however, commonly ischemia . The intestinal tract has an extensive collateral network presents a diagnostic challenge, with difficulty in differentiating that either prevents or limits bowel ischemia when central arter- between aortic and periaortic entities . Accurate interpretation of ies become obstructed . Familiarity with the collateral system is the imaging findings is crucial as clinical features may be nonspe- also vital to the interventionalist in many circumstances of treat- cific and biopsy is often difficult or unfeasible . Contrast-enhanced ing gastrointestinal bleeding . CT angiography, with its high spatial resolution, can provide excellent anatomic detail of the aorta and retroperitoneum, while contrast-enhanced MR provides superior soft tissue characteriza- E508. Abdominal Aortic Endovascular Stent Grafts: Pictorial tion . Dedicated protocols for these imaging modalities can pro- Review With Tips and Pitfalls in Characterizing vide valuable information to narrow the differential diagnosis of Complications Using Advanced 3D Postprocessing aortic and periaortic diseases and guide clinicians toward appro- Smith, A.; Bishop, P.; Shetal, S. Cleveland Clinic, University priate therapy . The purpose of this educational exhibit is to Heights, OH review the spectrum of abdominal aortic and periaortic diseases Address correspondence to A. Smith ([email protected]) and provide a practical CT and MR imaging approach to the diag- nostic dilemma of distinguishing between primary aortic and Background Information: Dynamic multiphasic contrast-en- periaortic diseases . hanced CT plays a vital role in preoperative planning and postop- erative surveillance of patients undergoing endovascular therapy Educational Goals/Teaching Points: Primary periaortic process- for abdominal aortic aneurysms . This pictorial review utilizing es usually do not cause aortic dilatation . Uncomplicated athero- conventional and advanced 3D postprocessing techniques; illus- sclerotic disease affects the wall of the aorta and spares the peri- trates various tips and pitfalls in detecting common postoperative aortic space . A combination of periaortic mass and aortic dilata- complications, and discusses their clinical implications . tion suggests an inflammatory or infectious process . Mural thick- ening, enhancement, and high signal on T2-weighted MR imag- Educational Goals/Teaching Points: Multiple case examples of ing suggests active aortic and periaortic inflammatory diseases . abdominal aortic endovascular stent graft CTs with 3D post- processing techniques will be presented to illustrate common Key Anatomic/Physiologic Issues and Imaging Findings/ complications, including endoleaks, stent fracture and stent Techniques: This exhibit will review the CT and MRI findings of migration . Multimodality correlates, including plain film, ultra- commonly and uncommonly encountered aortic and periaortic sound, and angiograms, will be presented when relevant . The entities, including diseases centered within the aorta itself reader will be able to appropriately protocol studies, characterize, (atherosclerotic processes such as plaque, penetrating aortic and interpret common and uncommon but important endovas- ulcer and abdominal aortic aneurysm, inflammatory aortitis, cular stent graft complications . mycotic/infectious aortitis, intramural hematoma, and dissection) as well as periaortic diseases (retroperitoneal fibrosis, lymphade- Key Anatomic/Physiologic Issues and Imaging Findings/ nopathy due to lymphoma or sarcoidosis, and metastatic dis- Techniques: In addition to evaluating source axial images, multi- ease) . Key findings and differentiating characteristics will be dis- planar reconstructions and 3D volume rendered are important in cussed, as well as specific imaging protocols that can facilitate readily detecting and confidently characterizing the various post- diagnosis . operative complications of abdominal aortic endovascular stent grafts, including various types of endoleaks, stent fractures and Conclusion: When confronted with an abnormal abdominal component migration . Scanning parameters, protocols and aorta, CT and MR are complimentary imaging modalities that advance 3D postprocessing techniques used for preoperative enable differentiation between primary aortic and periaortic dis- planning and postoperative surveillance will be discussed, espe- ease entities . cially in regards to the use of a native phase in pre- and postop- erative multiphasic CT exams . E510. Noninvasive Imaging With MDCT in Follow Up Aortic Conclusion: Conventional and advanced 3D postprocessing Aneurysm Stent Graft techniques are useful in identifying and characterizing various Laroia, A.; Laroia, S.; Abada, H. University of Iowa Hospitals and complications in patients following endovascular stent placement Clinics, Coralville, IA for abdominal aortic aneurysm . Knowledge of various tips and Address correspondence to A. Laroia (sandeeparchana@hotmail. pitfalls is critical for accurate diagnosis . com)

Background Information: The goals is to highlight the technical aspects of noninvasive evaluation with MDCT angiography in fol- low up of patients of abdominal aortic aneurysm treated with

346 El e c t r o n i c Ex h i b i t s : Interventional stent graft . The role of Doppler ultrasound and digital subtraction there was a statistically significant difference in procedure dura- angiography will also be discussed . tion (p<0 .01) and procedure fluoroscopy time (p<0 .01) . Between the TSA and the THA, there was a statistically significant differ- Educational Goals/Teaching Points: The exhibit will feature a ence in procedure duration (p<0 01). and procedure fluoroscopy discussion of the technical parameters for optimal imaging of the time (p<0 .01) . stent grafts in abdominal aortic aneurysm . Conclusion: The significant difference in procedure duration and Key Anatomic/Physiologic Issues and Imaging Findings/ procedure fluoroscopy time between the transtomal approach and Techniques: The key issues of discussion include scanning both the transjugular and transhepatic approaches translates into parameters, contrast injection protocols, importance of delayed a lower radiation dose when using the transtomal approach . A phase visualization techniques; the value of MDCT for the detec- detailed description of peristomal variceal embolization using the tion of endoleak and pre-embolization planning and an illustra- transtomal approach is provided with correlative imaging in hopes tion of all types of endoleaks on MDCT . of promulgating the use of this shorter, lower radiation procedure .

Conclusion: MDCT is a robust tool in the followup of patients receiving stent grafts for abdominal aortic aneurysm . Since the E512. Interventional Procedures in Obstetrics and noninvasive evaluation with MDCT is becoming more popular Gynecological Practice: A Pictorial Essay and better accepted by the sugeons in the follow up imaging of Laroia, S.; Abada, H.; Sun, S.; Laroia, A. University of Iowa the abdominal aortic aneurysm reapir with stent graft, the prac- Hospitals and Clinics, Coralville, IA ticing general radiologist needs to have a good understanding of Address correspondence to A. Laroia (sandeeparchana@hotmail. clinical concepts and imaging protocols .The exhibit is geared com) toward easy recall of various important technical parameters . Background Information: The aim of this exhibit is to review the various interventional radiological procedures in current E511. Transtomal Embolization of Bleeding Peristomal obstetrics and gynecological practice . Varices: A New Technique Pabon-Ramos, W.; Niemeyer, M.; Dasika, N. University of Educational Goals/Teaching Points: Review of the state of art Michigan, Ann Arbor, MI radiological intervention techniques in current obstetric-gyneco- Address correspondence to W. Pabon-Ramos (waleskap@med. logical practice . umich.edu) Key Anatomic/Physiologic Issues and Imaging Findings/ Objective: The objective is to describe a new technique for per- Techniques: The exihibit demostrate the following procedures: istomal variceal embolization, and compare it to two previously Embolization for post partum and post surgical bleeding, uterine described techniques . artery embolization, percutaneous drainage of uterine abscesses, cervical stenting, fallopian tube recanalization, radiofrequency Materials and Methods: The medical records and angiographic ablation of pelvic and vaginal tumors, drainage of pelvic fluid col- images of all patients who underwent peristomal variceal emboli- lections, transvaginal biopsy . All the topics will be well illustrated zation at the University of Michigan between January, 1998 and with images and relevant line diagrams . July, 2008 were retrospectively reviewed . Patients were classified as having undergone embolization through a transtomal Conclusion: The interventional radiologist can now offer many approach (TSA), transjugular approach (TJA), or transhepatic services to the obstetrician-gynecologist . This exhibit will highlight approach (THA) . For each approach, the median time interval various applications and focus on the technical aspects . between embolization and recurrent peristomal bleeding, medi- an procedure duration, and median procedure fluoroscopy time were calculated . The Wilcoxon Rank Sum test was performed to E513. Imaging of Prostate Brachytherapy Iodine-125 Seed determine if there was a difference in the time interval between Migration and Embolization embolization and recurrent peristomal bleeding, procedure dura- Nguyen, B.; Schoenfeldt, B.; Plumb, M.; Tollefson, C. Mayo Clinic, tion, and procedure fluoroscopy time between the TSA and the Scottsdale, AZ other two approaches . Lastly, transtomal embolization of peris- Address correspondence to B. Nguyen ([email protected]) tomal varices is described along with correlative imaging . Background Information: Transperineal prostate brachytherapy Results: Fifteen successful peristomal variceal embolizations is an established treatment option for localized prostate cancer were performed: six (40%) through the TSA, seven (47%) using ultrasound guidance for placement of iodine-125 seeds . through the TJA, and two (13%) through the THA . The median These implanted seeds have a high propensity to migrate away time interval between embolization and recurrent peristomal from the prostate gland via prominent periprostatic venous plex- bleeding was 45 days for the TSA, 63 days for the TJA, and 30 uses . The authors present an education exhibit on iodine-125 days for the THA . The median procedure duration was two seed migration and embolization to different parts of the body hours 47 minutes for the TSA, four hours 20 minutes for the TJA, documented on radiographs and cross-sectional imaging . and six hours 25 minutes for the THA . The median fluoroscopy time was 16 minutes for the TSA, 63 minutes for the TJA, and 88 Educational Goals/Teaching Points: In this exhibit, the authors minutes for the THA . Between the TSA and the TJA, there was no describe the prostate brachytherapy technique and characteristics statistically significant difference in the time interval between of the iodine-125 seeds; present the different circulatory path- embolization and recurrent peristomal bleeding (p=0 01),. but ways of migration and embolization of these seeds; review the

347 El e c t r o n i c Ex h i b i t s : Interventional radiographic and scintigraphic features of seed relocation at dif- jectory from skin entry to the target point and allows procedures ferent sites and organs, and discuss outcomes and potential clini- to be performed more rapidly, safely and efficiently . cal complications induced by seed embolization .

Key Anatomic/Physiologic Issues and Imaging Findings/ E515. Treatment of Chylothorax: A Primer (CME Credit Techniques: This education exhibit uses the pictorial essay for- Available) mat to show different sites of seed embolization encompassing Jain, R.; Campagna, J.; Ray, C. University of Colorado, Golden, CO lungs, right atrial, right atrial appendage, right ventricle, vertebral Address correspondence to C. Ray ([email protected]) venous plexuses, liver, left ventricle, and organs with systemic vascular supply such as spleen and kidneys . At each location, Background Information: Disruption of the thoracic duct results imaging features of seed embolization and related diagnostic pit- in chylothorax, which can be a life-threatening condition . Surgical falls are discussed in correlation with seed characteristics . interventions are costly, risky, and are frequently unsuccessful . In Emphasis is on the vigilance of imaging interpretation to achieve addition, patients presenting with chylothorax are often seriously the correct identification of seed embolization . ill, which may preclude open surgical procedures . Interventional techniques are difficult to perform, but are generally significantly Conclusion: After the viewing of this exhibit, the participants less morbid than open techniques . understand the prostate brachytherapy procedure and iodine- 125 seed characteristics; have full awareness of frequent seed Educational Goals/Teaching Points: The goals are to provide migration and related pathways of embolization, and are capable an overview of the clinical and radiologic presentations of chylot- of diagnosing embolization events at different sites of the body . horax; to present the state of the art of the treatment (medical, surgical, and interventional radiologic) for chylothorax, and to review the interventional radiologic techniques used during E514. Value of Multislice CT Fluoroscopy in Guiding Lung embolization of the thoracic duct . and Abdominal Biopsy Tappouni, R.1; Sarwani, N.1; Policare, C.2 1. Penn State, Hershey, Key Anatomic/Physiologic Issues and Imaging Findings/ PA; 2. Milton S. Hershey Medical Center, Hershey, PA Techniques: Chylothorax is a severe and often life-threatening Address correspondence to R. Tappouni ([email protected]) clinical condition with few therapeutic options . The percutaneous approach is often advantageous compared to surgical interven- Background Information: The accuracy and safety of imaging- tion due to the use of local anesthesia and conscious sedation guided percutaneous needle biopsy procedures have been well vs . general endotracheal anesthesia and lung decompression, documented . Because percutaneous biopsy is less invasive and especially in this often critically ill population . Percutaneous inter- more cost-effective than surgery, the number of radiologic proce- vention can be attempted immediately following the diagnosis of dures performed each year continues to increase . With the devel- chylothorax to help avoid long-term complications and costs opment of multislice CT fluoroscopy, there is now real-time associated with conservative management with initial success image reconstruction, rapid imaging update of needle position, rates around 70% with lower morbidity and mortality compared and convenient, in-room table control and image viewing . These to surgical intervention (<5 % vs . 25-40%) . developments allow for the needle sampling of smaller lesions and decreased procedure times . Poor breath holders can Conclusion: Percutaneous techniques used in the treatment of also undergo lung biopsies due to rapid image acquisition time . chylothorax are the most minimally invasive and may be the most cost-effective method by which to treat chylothorax . Educational Goals/Teaching Points: The goals are to review the advantages of CT fluoroscopy in sampling lesions in the lung and the abdomen . These will be presented in the following cate- E516. High Stakes Mediastinal Interpretation: A Pictorial gories: reduction the total procedure time and therefore increase Collection of Mediastinal Vascular Injuries resource utilization; increased diagnostic yield; reduction of radia- Rehmani, R.; Chu, P.; Krumenacker, J. Nassau University Medical tion dose to the patients; reduction of complication rates . Center, East Meadow, NY Address correspondence to R. Rehmani ([email protected]) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: An autototutorial will consist of text, pictures and CT Background Information: The goal is to familiarize the reader examples divided into four main categories . We will present with the spectrum of vascular injuries of the mediastinum, espe- our experience with total procedure time, diagnostic yield and cially their key imaging features, in order to prevent errors in complication rates . Various methods to reduce the radiation dose interpretation which would have potentially disastrous conse- to the patient and the operator will be presented . The exhibit will quences for the patient . also describe various techniques that could be used to increase the diagnostic yield and to reduce complications . Novel technical Educational Goals/Teaching Points: We will demonstrate and approaches in needle positioning during real time fluoroscopy describe a variety of manifestations of mediastinal vascular inju- while avoiding radiation to the operator’s hand will be presented . ries, including some unusual injuries from blunt, penetrating and Also, we present a technique for the use of IV contrast in a iatrogenic causes . These will be displayed as an interactive didac- dynamic fashion using CT fluoroscopy to aid in the biopsy of tic educational exhibit in electronic format . a small hypervascular liver lesion . Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: The use of CT fluoroscopy facilitates CT-guided biop- Techniques: We retrospectively reviewed the imaging studies sy procedures, by allowing rapid visualization of the needle tra- (plain radiographs, MDCT with 2D and 3D reconstructions, and

348 El e c t r o n i c Ex h i b i t s : Interventional angiograms) of patients with iatrogenic and blunt mediastinal E518. Noninvasive Evaluation of Peripheral Arterial Disease vascular trauma, performed during the past ten years at our Level With MDCT one trauma center . The images were reviewed for injury location, Laroia, S.; Abada, H.; Laroia, A.; Youness, F. University of Iowa morphology and extent .We found mediastinal vascular injuries Hospitals and Clinics, Coralville, IA from blunt trauma have a multitude of presentations and are not Address correspondence to A. Laroia (sandeeparchana@hotmail. simply confined to transection and pseudoaneurysms of the tho- com) racic aorta . In addition to aortic injuries we present a number of cases where the injuries were not of the aortic origin . Some of Background Information: The purpose of this exhibit is to illus- these may mimic aortic injury . These include unusual cases such trate the role of MDCT in assessment of peripheral arterial dis- as isolated brachiocephalic, pulmonary, carotid and intercostal ease (PAD) . vascular injuries . Mediastinal vascular injuries may also result from iatrogenic causes, specifically from placement of transvascu- Educational Goals/Teaching Points: The goals are to review lar catheters . We present several cases of mediastinal vascular the imaging of noninvasive evaluation of PAD with MDCT, and injuries related to catheter placement in order to emphasize the discuss the technical aspects and the postprocessing techniques often overlooked possibility of an iatrogenic cause when evaluat- in evaluation of PAD with MDCT . ing mediastinal hemorrhage in hospitalized patients . Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: Injuries to the major vessels of the mediastinum are Techniques: The exhibit will feature a discussion on the scan- often life threatening, requiring immediate intervention . Therefore ning parameters, contrast injection protocols, radiation dose prompt recognition of these injuries, regardless of the etiology, will reduction, visualization strategies and their pros and cons, the have a major impact on maximizing favorable patient outcome . impact of various clinical scenarios in PAD on imaging protocol, and pitfalls . The information presented will be well illustrated .

E517. MDCT Angiography of Iliac and Femoral Arteries in the Conclusion: Optimium imaging of PAD with MDCT requires a Endograft Presurgical Planning good understanding of technical issues so adequate emphasis Saba, L.; Sanfilippo, R.; Caddeo, G.; Montisci, R.; Mallarini, G. will be given to this aspect . The attendee should be able to set A.O.U, Cagliari Sardegna, Italy up an optimized protocol for patients with PAD after going Address correspondence to L. Saba ([email protected]) through the exhibit .

Background Information: The purpose of this exhibit is to describe the normal anatomy of iliac and femoral arteries; to E519. Imaging Manifestations of Vascular Thrombosis: review pathology of iliac and femoral arteries as stenosis, dissec- Arterial and Venous tions, aneurysms and tortuosity and the impact of this patholo- Khosa, F.; Dubey, P.; Sarwar, S.; Khan, A.; Camacho, M.; Clouse, gies in the endograft presurgical planning; to review the MDCT M.; Raptopoulos, V. Beth Israel Deaconess Medical Center, angiography (MDCTA) technical parameters to be used and Brookline, MA which postprocessing techniques can be employed, and to ana- Address correspondence to F. Khosa ([email protected]) lyze cost and biological impact (contrast material, ionizing radia- tion) of an MDCTA exam before endograft procedure . Background Information: Vascular thrombosis (VT) is a multi- causal disorder . It is frequently encountered in the hospital/clini- Educational Goals/Teaching Points: The exhibit will include cal setting and is responsible for a substantial amount of comor- normal anatomy of iliac and femoral arteries; pathology of iliac bidity and mortality . This may be due to hypercoagulable effects, and femoral arteries (stenosis, aneurysms and tortuosity); the direct invasion by the neoplasm, direct or indirect effects of chem- role of iliac and femoral arteries in the presurgical planning for otherapy, hormonal therapy or radiotherapy, the presence of ind- endograft positioning; MDCTA technical parameters to be used welling central lines, and following bone marrow transplantation . and which postprocessing techniques should be applied; a com- parison of MDCTA with digital subtraction angiography, ultra- Educational Goals/Teaching Points: The radiologist may be the sound and MR, and presentation of relevant cases . first clinician to suggest and diagnose either venous or arterial thrombus, especially in cases when it is not expected or is with- Key Anatomic/Physiologic Issues and Imaging Findings/ out immediate clinical consequence . Therefore it is imperative, to Techniques: In this educational exhibit we will present several establish sound knowledge and familiarity with the radiographic iliac and femoral arteries images, by using MDCTA axial and post- findings of both direct and indirect signs of VT, avoiding signifi- processed volume rendering, maximum intensity projection and cant morbidity and mortality . curved planar reconstruction) methods . Several cases of stenosis, dissections, aneurysms and tortuosity were presented and dis- Key Anatomic/Physiologic Issues and Imaging Findings/ cussed by underlining their effect in the endograft presurgical Techniques: The imaging modalities employed for detection and planning . diagnosis of VT are many . Once thrombosis is suspected, depending on the region involved and circulatory system, stand- Conclusion: Precise analysis of iliac arteries is fundamental for ard objective investigations (Doppler ultrasound, ventilation per- endograft presurgical planning . MDCTA is a valuable tool to study fusion scanning, CT, MR venography and conventional angiogra- iliac arteries . The use of postprocessing procedures determines phy,) can be utilized for diagnosis, extent, follow up and illustra- optimal results; in particular volume rendering and maximum tive presentation . There are four main radiological presentations intensity projection techniques allow for excellent anatomic detail . of VT: direct local invasion (e .g . sarcoma invading directly into surrounding vessels); intravascular extension of primary tumor;

349 El e c t r o n i c Ex h i b i t s : Interventional hypercoagulable states and vascular stasis leading to throm- E521. Angiographic Spectrum of Upper Extremity Arterial boembolism, and thrombosis related to long term central lines Occlusive and Thromboembolic Disease and chemoradiotherapy . There are two circulatory systems at risk McNulty, N.1; Forauer, A.1; Cwikiel, W.2 1. Dartmouth-Hitchcock for vascular thrombosis, the “arterial” and the “venous” circulato- Medical Center, Lebanon, NH; 2. University of Michigan Medical ry systems . The formation of thrombi in both, are the result of Center, Ann Arbor, MI continuous interplay of factors like local anatomy, stenosis, for- Address correspondence to N. McNulty (Nancy.McNulty@hitch- eign bodies as well as homeostatic factors like platelets, cock.org) endothelial surface and coagulation proteins in circulation . Background Information: Despite advances in noninvasive Conclusion: This illustration will take the form of a didactic pres- imaging techniques such as MR angiography, CT angiography, entation . Through a pictorial review, we intend to illustrate the and duplex ultrasound, catheter based angiography remains the spectrum and emphasize the imaging features of VT as seen on primary diagnostic tool in the investigation of upper extremity ventilation perfusion scans, radionuclide and conventional venog- ischemic disorders . We present the spectrum of angiographic raphy, ultrasound, CT, MRI and PET-CT . findings and clinical manifestations of the more common etiolo- gies of upper extremity arterial occlusive and thromboembolic disease . E520. Interventional Radiologic Techniques in the Treatment of Extremity Trauma: State of the Art (CME Credit Educational Goals/Teaching Points: The goals are to review Available) the clinical presentation, manifestations, and angiographic find- Vu, C.; Tivorsak, T.; Ray, C. University of Colorado, Golden, CO ings in arterial occlusive and thromboembolic disorders of the Address correspondence to C. Ray ([email protected]) upper extremity, and to discuss the differentiation of acute and chronic occlusions on angiographic images and review the con- Background Information: Traumatic injury to the extremities is cept of collateral circulation . At the end of this exhibit, the learner a common form of injury presenting to urban Level One trauma should have a thorough understanding of the differential diagno- centers . With the trend in nonoperative management of traumat- sis of upper extremity ischemia, and the angiographic manifesta- ic injuries to other organs as well as the extremities, intervention- tions of these disorders . al radiologic techniques have becoming increasingly important in the management of such injuries . Due to the nature of the injury, Key Anatomic/Physiologic Issues and Imaging Findings/ as well as considerations for the vascular supply to the extremi- Techniques: The technique of diagnostic upper extremity angiog- ties, interventional radiologic management of acutely injured ves- raphy is reviewed, including the use of intra-arterial vasodilating sels of the upper and lower extremities presents a different set of agents . The most common etiologies of upper extremity occlusive management issues that must be considered for each patient . and thromboembolic disease are presented with an emphasis on angiographic findings and interpretation; differentiating acute Educational Goals/Teaching Points: The goals are to present from chronic vascular occlusions, and establishing a differential an overview of the current state of the art for management of diagnosis of upper extremity occlusive disease . extremity trauma through a brief review of the seminal and recent literature; to review normal and variant anatomy that is Conclusion: The etiology and pathophysiology of upper limb pertinent to interventional techniques used in the treatment of ischemia is quite diverse, in contrast to that of the lower limb extremity trauma, and to discuss technical issues to be consid- which is more typically due to atherosclerotic and thromboem- ered for this patient population, particularly when compared to bolic disease . Disruptions of the blood supply in the proximal other organ systems undergoing post-traumatic endovascular limb can have variable clinical manifestations in the distal limb . therapy . We present the spectrum of angiographic findings of upper extremity occlusive and thromboembolic disease . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The choice of endovascular techniques used in the setting of extremity trauma may be limited due to the need to E522. Bleeding and Thrombosis Risk Assessment and retain downstream flow to the extremity . Recent developments in Management for Radiology Patients Receiving Antiplatelet endovascular techniques have broadened the application of such and Anticoagulant Therapy techniques in the trauma population . Choudhary, S.1,2; Fraser-Hill, M.1; Scarvelis, D.1; Rodger, M.1 1. The Ottawa Hospital, Ottawa, Canada; 2. University of Texas Conclusion: Endovascular techniques often provide an attractive Health Science Center at San Antonio, San Antonio, TX alternative to surgical procedures in the setting of extremity trau- Address correspondence to S. Choudhary ([email protected]) matic injury . Background Information: The number of patients who require maintenance on anticoagulation or antiplatelet therapy for mini- mizing risk of cardiovascular events like stroke or thromboembo- lism is increasing . A major problem is then encountered when these patients need to undergo surgery or any other invasive pro- cedure . Minimally invasive, percutaneous imaging-guided proce- dures including diagnostic and therapeutic angiograms, percuta- neous nephrostomies, biliary drainages, abscess/fluid drainages, arthrograms and biopsies of the spine, bone, lung, kidney, liver, peritoneum, intrathoracic or abdominopelvic lymph nodes and

350 El e c t r o n i c Ex h i b i t s : Interventional soft tissue masses are now increasingly performed routinely . Conclusion: The radiologist should be able to recognize normal, Postprocedure hemorrhage represents a potentially serious com- abnormal, and variant positioning of inferior vena cava filters on plication of these procedures, particularly for patients on CT; recognize the different types of IVC filters on CT, and utilize antiplatelet and anticoagulant therapies . Despite many years of CT to evaluate for complications of IVC filters . routine interventional practice, no specific guidelines exist on modification of these drugs prior to invasive procedures . Using evidence from literature, we have defined two risk categories for E525. Congenital Anomalies of the Inferior Vena Cava: thromboembolism and proposed guidelines for the management Cross-Sectional Imaging and Clinical Implications of imaging-guided interventions for patients on antiplatelet and Kakarla, R.; Gueyikian, S.; Saker, M.; Vaghani, A. Illinois Masonic anticoagulant therapy . Medical Center, Chicago, IL Address correspondence to R. Kakarla ([email protected]) Educational Goals/Teaching Points: This exhibit will review common antithrombotic therapies including warfarin, heparin, Background Information: Due to complex embryological devel- low molecular weight heparin and antiplatelet agents, and how opment of the inferior vena cava (IVC), multiple variations can they affect coagulation profiles; common coagulation blood tests occur in venous anatomy . Some of these variations have signifi- and what they mean; practical pre- and postbiopsy management cant clinical implications . As it might be difficult to distinguish strategies for patients receiving antiplatelet and anticoagulant vascular anomalies and variations on noncontrast CT, it is essen- therapy, considering the risks of bleeding and thrombosis, and tial to be aware of these variations and their imaging appearance when to consider hematology consultation and what recommen- in order to avoid diagnostic pitfalls . dations to expect . Educational Goals/Teaching Points: The purpose of this exhibit Key Anatomic/Physiologic Issues and Imaging Findings/ is to review the embryogenesis of the IVC and describes the vari- Techniques: This educational exhibit reviews evidence-based ations in IVC anatomy . The CT and MRI appearances of the more multidisciplinary guidelines developed at The Ottawa Hospital frequently encountered anomalies and some unusual variants concerning bleeding and thrombosis risk assessment and man- will be presented . The clinical relevance of the variations will also agement of imaging-guided interventions for patients on be discussed . antiplatelet and anticoagulant therapy . Key Anatomic/Physiologic Issues and Imaging Findings/ Conclusion: After viewing this exhibit, radiologists will have a Techniques: The exhibit will include embryogenesis (four seg- clearer understanding of bleeding and thrombosis risk manage- ments of IVC and origins)and imaging presentation of common ment for patients on anticoagulant and antiplatelet therapies variations (duplicated IVC, left sided IVC, azygous continuation of prior to interventional procedures such as percutaneous biopsy . the IVC, absence of infrarenal IVC, absence of entire IVC, double IVC with retroaortic left renal vein and azygos continuation, dou- ble IVC with rertoaortic right renal vein and hemiazygous contin- E524. Inferior Vena Cava Filters on Abdominal CT: uation, circumaortic/retroaortic left renal vein, and circumcaval Identification, Positioning, and Complications urete) . Georgiou, N.1; Hon, M.1; Katz, D.1; Trost, D.2 1. Winthrop- University Hospital, Mineola, NY; 2. New York Hospital, Weill- Conclusion: Many of the variations of IVC anatomy have clinical Cornell Medical Center, New York, NY implications that present themselves either during surgery, Address correspondence to D. Katz ([email protected]) planned interventions or in pathologic conditions . It is essential for the diagnostic radiologist to be aware of the variants in IVC Background Information: Inferior vena cava (IVC) filters, wheth- anatomy and be able to accurately describe it to the referring er permanent or temporary, are routinely identified on CT exami- physician and surgeon as applicable . These entities may be readi- nations of the abdomen performed for various reasons . Usually ly recognizable on contrast-enhanced CT by radiologists aware of they are incidental or not the primary reason the scans are their presence, but knowledge of embryogenesis and variant obtained, but occasionally CT may be performed (either routine anatomy will allow diagnosis on any of the variety of imaging abdominal or pelvic CT, or as part of CT venography) to specifically techniques . identify a suspected problem such as incorrect placement or asso- ciated thrombosis related to the filter, or rarely for complications such as caval perforation or secondary urinary tract obstruction . E526. Imaging of Congenital Inferior Vena Cava Anomalies Dobtsis, J.; Dillon, E.; Epstein, N. Lenox Hill Hospital, New York, NY Educational Goals/Teaching Points: The purposes of this exhibit Address correspondence to J. Dobtsis ([email protected]) are to demonstate the spectrum of IVC filters as seen on CT; to show the normal and variant positioning of IVC filters, includ- Background Information: During the early first trimester, the ing the incorporation of the filter into the IVC wall, and to show formation of an inferior vena cava takes place . Inferior vena cava examples of complications of IVC filter placement using CT . (IVC) anomalies reflect an abnormal regression or persistence of the various embryonic veins . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: CT examples of degrees of tilting of filters, purpose- Educational Goals/Teaching Points: The exhibit will highlight ful positioning above the renal veins, in duplicated IVCs, or place- embryology of inferior vena cava anomalies and characteristics ment of more than one filter will be shown . The current literature and imaging features of congenital vena cava anomalies . on the appearance, location, and complications of IVC filters as shown with CT will be reviewed .

351 El e c t r o n i c Ex h i b i t s : Interventional

Key Anatomic/Physiologic Issues and Imaging Findings/ examination of significant collateral pathways and their imaging Techniques: A detailed discussion including embryologic origins manifestations will be included . Finally, treatment options will as well as imaging characteristics of the following inferior vena also be addressed . The goal is to develop a confident approach cava congenital anomalies will be presented: interruption of the to diagnosis of central venous occlusion of the upper body across IVC with azygos or hemiazygos continuation, IVC transposition, multiple modalities and to familiarize the radiologist with rele- IVC duplication, retroaortic and circumaortic left renal vein, periu- vant clinical aspects of the condition as well as available treat- reteric venous ring, and retrocaval ureter . ment options .

Conclusion: A wide variety of congenital anomalies affects the inferior vena cava . It is very important for the radiologist to recog- E528. Value of Unenhanced CT in Diagnosis of Clinically nize these anatomic variants to avoid their misinterpretation as Significant Vascular Abnormalities well as to make the treating physician aware of them prior to Gakhal, M.; Sartip, K. Christiana Care Health Services, New surgical and interventional procedures . Castle, DE Address correspondence to K. Sartip ([email protected])

E527. Central Venous Occlusion: Back to the Heart of the Background Information: There are a variety of reasons where- Matter by acutely ill patients or those presenting to the emergency room Covarrubias, D.; Loona, J.; Flamini, D.; Leonardo, R.; Martino, J. may undergo an unenhanced CT rather than the desired study Long Island College Hospital, Brooklyn, NY with intravenous contrast . In addition, some patients in whom Address correspondence to D. Covarrubias (dcovarru@chpnet. noncontrast studies such as kidney stone protocol CT are specifi- org) cally ordered are eventually determined to have symptoms that are not of urologic origin . A subset of such patients has symp- Background Information: The exhibit will review anatomy and toms attributable to vascular etiology . Although the vascular physiology of the central veins of the upper extremity and the structures are optimally assessed on contrast-enhanced studies, major clinical etiologies of occlusion; demonstrate a variety of important vascular pathology can be diagnosed or suspected on cases that depict the typical imaging appearance of central the basis of an unenhanced CT, and should not be overlooked . venous occlusion with correlation of angiographic and CT find- This exhibit will discuss, via case examples, the imaging features ings; review collateral drainage pathways in cases of superior and manifestations of clinically relevant venous and arterial vena cava, subclavian, and axillary vein occlusion, and discuss abnormalities that can be detected on unenhanced CT, and pertinent aspects of clinical management of central venous occlu- which have significant impact on patient management and out- sion . come .

Educational Goals/Teaching Points: Upon completion of this Educational Goals/Teaching Points: The goals are to describe exhibit the viewer will have familiarized themselves with the nor- the imaging features and manifestations of a variety of significant mal central venous anatomy of the upper extremity; become well and acute processes affecting the venous or arterial system on acquainted with the most common causes of central venous non contrast CT, and to illustrate and reinforce the importance of occlusion and their corresponding clinical presentations, and analyzing vascular structures on unenhanced CT . developed an understanding of the imaging appearance of cen- tral venous occlusion and basic aspects of management . Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: The authors will describe through case examples Key Anatomic/Physiologic Issues and Imaging Findings/ the imaging features of clinically significant vascular abnormali- Techniques: The exhibit will consist of an overview of anatomy ties that can be encountered on unenhanced CT . Examples in the and physiology of the central veins of the upper extremity; a dis- venous system will focus on acute thrombosis of the superior cussion of clinical scenarios that lead to occlusion; a discussion mesenteric, inferior mesenteric, portal, renal, iliac and ovarian of imaging work up of suspected central venous occlusion; a dis- veins . Additional entities will include venous neoplastic invasion, play of imaging findings at angiography in cases of occlusion arteriovenous malformation, and varices . Examples in the arterial caused by various etiologies, with inclusion of correlation with system will include aortic intramural hematoma, dissection, early other imaging modalities; an examination of common collateral or impending aortic aneurysm rupture, as well as pulmonary drainage pathways in the setting of occlusion, and consideration embolus . of clinical management of central venous occlusion, including medical and interventional therapies . Conclusion: Clinically significant venous and arterial abnormali- ties can in some instances be detected on unenhanced CT, and Conclusion: As the number of patients requiring extended cen- should not be overlooked . The vascular structures should be tral venous access continues to rise, central venous thrombosis of closely scrutinized as a potential source of patient symptoms, the upper body has become an increasingly common clinical and should be part of the systematic image review process, even dilemma . Diagnosis and often management of these conditions on unenhanced CT examinations . depends heavily on multimodality imaging . The purpose of this exhibit is to review the relevant anatomy of the venous system of the upper torso and extremities and to portray the imaging find- ings of both primary and secondary causes of central venous occlusion . The primary modalities considered will be venography and CT, with correlation of findings between the two . A brief

352 El e c t r o n i c Ex h i b i t s : Interventional

E529. Carotid Artery Stenosis and Renal Artery Stenosis, are Conclusion: In the work-up of patients with suspected vasculitis, they Associated? A Study by Using MDCT Angiography cross-sectional imaging with CT (and CT angiography), and MR Saba, L.; Mallarini, G. A.O.U, Cagliari Sardegna, Italy (and MR angiography) are invaluable tests, often obviating the Address correspondence to L. Saba ([email protected]) need for conventional angiography . An awareness of the multi- tude of imaging manifestations of vasculitis is essential as the Objective: Hypertension due to renal artery stenosis (RAS), usu- radiologist is often the first to suggest the possibility of one of ally produced by atherosclerosis, has been established as a cause these fascinating and diverse conditions . of hypertension because of the activation of the renin-angi- otensin system, whereas carotid artery stenosis is the most important cause of stroke . The purpose of this work is to evalu- E531. Peripheral Vascular Malformations and Extremity ate, by using multidetector-row spiral CT angiography (MDCTA), if Hemangiomas Revisited: MRI Features with Angiographic a relationship between accessory renal arteries stenosis and Correlation and Overview of Controversies Regarding Their carotid artery stenosis may be hypothesized . Classification and Management Sunnapwar, A.; El-Merhi, F.; Cura, M. University of Texas Health Materials and Methods: Sixty-eight patients (63 males; 25 Science Center at San Antonio, San Antonio, TX females, mean age: 63 years) that previously had undergone a Address correspondence to A. Sunnapwar (sunnapwar@uthscsa. MDCTA to study the abdominal vasculature and carotid arteries edu) were retrospectively studied . The patients were studied by using a four-detector-row CT and scans were obtained after intrave- Background Information: There exists a lot of controversy and nous bolus administration of 110-140 mL of a nonionic contrast confusion regarding nomenclature and classification of various material using a 3-6 mL/sec flow rate . We reviewed exams for peripheral vascular malformations (PVM) and peripheral heman- renal arteries stenosis and carotid artery stenosis . Two radiolo- giomas . For example, Maffucci syndrome which was first gists first independently reviewed the MDCTA images and if disa- described in 1881 as multiple enchondromas combined with greement in consensus . Cohen kappa statistics for agreement hemangioma is actually a misnomer . According to the newest was performed . A chi-square and a simple logistic regression classifications the associated abnormality is not a hemangioma analysis were performed in order to calculate the association but actually is a venous malformation . Thus, knowledge of vari- between parameters . ous types of peripheral lesions is extremely important to the diagnostic radiologist as well as to the treating team which usu- Results: We observed 12 patients with renal artery stenosis and ally include an interventional radiologist, vascular surgeon, der- 59 patients with carotid artery stenosis, and we observed a statis- matologist and a pediatrician . Management of these distinct enti- tically significant association between these two conditions ties differs considerably and the prognosis also varies . The pur- (p>0 027). odds ratio 1 99);. in logistic regression analysis we pose of this exhibit is to discuss MRI features of various PVMs observed an association between renal artery stenosis and hyper- with angiographic correlation . To the author’s knowledge there tension (p=0 .029 odds ratio 2 .12) . has been no article so far in the literature that describes correla- tion of these two imaging modalities . We will also discuss various Conclusion: We observed a statistically significant association classifications and controversies, the clinical presentation, and between renal artery stenosis and carotid artery stenosis . management of PVMs .

Educational Goals/Teaching Points: The goals are to present E530. Imaging of Large and Medium-Sized Vessel Vasculitis MRI features of various PVMs with angiographic correlation; dis- Rebello, R.1; Muhn, N.1; Pavlov, V.1; Khalidi, N.1; Harish, S.1; Wu, cuss new classification systems of PVMs and associated contro- L.2; Prabhudesai, V.3 1. St. Joseph’s Healthcare, Hamilton, versies, and discuss clinical presentations and management of Ontario, Dundas, Canada; 2. Oshawa General Hospital, Oshawa, PVMs . Canada; 3. St. Michael’s Hospital, Toronto, Canada Address correspondence to R. Rebello ([email protected]) Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Hemangiomas are classified as benign neoplasm Background Information: The vasculitides are a diverse collec- whereas peripheral vascular lesions are actual malformation of tion of diseases with protean manifestations affecting virtually the vessels involved . Hemangiomas have proliferative endotheli- every organ system . The primary objective of this exhibit is to um whereas PVMs have stable endothelium . The PVMs can be demonstrate the vascular abnormalities and end-organ changes simple or combined . Some authors have proposed classification associated with large and medium-sized vessel vasculitides . based on their flow pattern .

Educational Goals/Teaching Points: After reviewing this exhib- Conclusion: We present MRI features of various PVMs with angi- it, the reader should be familiar with the main CT, MRI and angi- ographic correlation, and discuss briefly the various new classifi- ographic findings of these various diseases . cation systems and associated controversies . Accurate diagnosis of these entities is important because improper management is Key Anatomic/Physiologic Issues and Imaging Findings/ associated with serious complications, including life-threatening Techniques: Tailoring MRI/MR angiography protocols to depict hemorrhage and limb loss . the luminal and mural changes associated with these vasculitides will also be discussed . Mimics of these diseases and pitfalls in vasculitis imaging will be reviewed .

353 El e c t r o n i c Ex h i b i t s : Interventional

E532. Intraforaminal Lumbosacral Discal Herniation: drastically reduced surgical blood loss by an average of 60-70%, Treatment of Symptomatic Patients with Intraforaminal but there has also been an improvement in the visualization of Injection of Oxygen-Ozone (02-03) Mixture the operative field and a decrease in operating time . Additional Angileri, T.1; Verderame, F.1; Banco, A.2; Sparacia, G.2; Bartolotta, benefits of vertebral tumor embolization include tumor shrink- T.2; Taibbi, A.2 1. Villa Santa Teresa, Bagheria, Palermo, Italy; 2. age, pain relief and a lower rate of tumor recurrence postproce- University Hospital, Palermo, Italy dure . The purpose of this education exhibit will be to showcase Address correspondence to A. Taibbi ([email protected]) the radiographic findings of vertebral tumor embolization with the use of MR imaging, CT and angiographic imaging . Objective: The objective is to evaluate the efficacy of treatment with intraforaminal injection of oxygen-ozone (O2-O3) mixture in Educational Goals/Teaching Points: The goals are to describe symptomatic patients suffered from intraforaminal discal herniation . the adjunctive role of vertebral tumor embolization in tumor resection, and the importance of creating a roadmap in order to Materials and Methods: From January, 2000 to June, 2006, 92 ensure super-selective, sufficiently distal embolization of tumoral symptomatic patients with intraforaminal discal herniation con- blood supply . This prevents necrosis of normal tissues which may firmed by CT and/or MR, underwent treatment with oxygen-ozone share a common proximal artery, as well as revascularization of (O2-O3) mixture (3-4 mL), corticosteroid and anaesthetic by tumoral vasculature through delayed revascularization . means of intraforaminal injection . All patients had already under- gone conservative therapy for 45 days without any success with Key Anatomic/Physiologic Issues and Imaging Findings/ score variable from 8 to 10 at VAS test . Forty-seven of 92 (51 1%). Techniques: The exhibit will provide a review of MR and CT patients presented with L4-L5 disk herniation; 30/92 (32 6%). images of vertebral bone tumor, and give the participant in the with L5-S1 disk herniation; 12/92 (13%) with L3-L4 disk hernia- activity an appreciation of changes in tumor blush pre- and tion and, finally, three out of 92 (3 .3%) with L2-L3 disk hernia- postembolization. tion . All patients underwent two intraforaminal injections under CT guide at an interval time of 15 days . VAS test was performed Conclusion: Vertebral tumor embolization is a safe and useful just before the former injection (T0), 15 days later just before the adjunct to surgical manipulation of both metastatic and primary latter (T1) and one month after the second injection (T2) . tumors of the spine . With recognition of radiographic features such as tumor blush and necrosis, disease progression can be Results: In 59/92 patients (65%) a partial remission of the com- effectively monitored both during the procedure as well as post- plaints was observed after the first treatment (VAS range: 4-6 at operatively. T1) . After the second treatment, one month later, in 75/92 patients (82%) a significant remission of the complaint was observed (VAS=3 at T2) whereas 13/92 (14 1%). presented VAS E534. Temporary Embolic Agents Used in Interventional value=7 and four out of 92 (4 .3%) did not show any improve- Radiology: An Update ment (VAS range: 8-10 at T2) . Six months after the first injection, Brinckman, M.; Ray, C. University of Colorado, Golden, CO all patients underwent CT or MR examination . In 20/92 cases Address correspondence to C. Ray ([email protected]) (21 .7%) a significant shrinkage of disk herniation was observed and all these patients have already showed good results at T1 . Background Information: Embolic agents are used routinely in interventional radiology . In select circumstances, a temporary Conclusion: CT-guided intraforaminal injection of O2-O3 mixture occlusion of a vessel is preferable to permanent occlusion . The associated with corticosteroid and anaesthetic is a safe and effec- earliest agent used for temporary occlusion (autologous clot) is tive tool for the treatment of intraforaminal discal herniation, sig- rarely used in current clinical practice . There are now many com- nificantly relieving lower back pain . mercially available temporary agents, each with distinct benefits and drawbacks .

E533. Radiographic Findings (MR, CT, Angiography) of Educational Goals/Teaching Points: The purpose of this edu- Vertebral Tumor Embolization cational exhibit is to present the current state of temporary Chen, C.; Lee, E.; Hoffman, C.; Loh, C.; Kee, S. University of embolic agents . Specific topics discussed will include identifica- California-Los Angeles Medical Center, Los Angeles, CA tion of the various temporary agents currently used during Address correspondence to E. Lee ([email protected]) embolization procedures; clinical scenarios in which temporary agents might be used; technical issues related to the use of indi- Background Information: Metastases from nonosseous primary vidual agents, and trouble-shooting techniques used when stand- neoplasms comprise the majority of vertebral tumors, accounting ard protocols fail . for approximately 90% of all tumors of the spine . Depending on the primary site, vertebral metastases may be hypervascular, Key Anatomic/Physiologic Issues and Imaging Findings/ examples being those of renal cell carcinoma in origin . Similarly, Techniques: Temporary agents are used in different clinical sce- certain primary vertebral neoplasms can be associated with a narios than most permanent agents . Technical differences must high degree of hypervascularity as well, including giant cell be considered when using temporary agents . tumors, aneurismal bone cysts and most malignant growths . Prior to the advent of transarterial embolization, resections and Conclusion: Used in the correct clinical scenario and with atten- other surgical management of hypervascular vertebral tumors tion to technique, temporary agents may prove to be far more consistently resulted in massive intraoperative hemorrhage . advantageous than permanent agents . Individuals performing However, since the adoption of preoperative embolization of embolization procedures must be familiar with the currently bone tumors, this interventional radiology procedure has not only available agents and the nuances of working with such agents .

354 El e c t r o n i c Ex h i b i t s : Interventional

E535. Contrast-Enhanced MR Angiography in the E536. Interventional Oncology 101: A Comprehensive Nephrogenic Systemic Fibrosis Era: Contrast Dose Reduction Review of the Armamentariums of Interventional Oncology With the Use of a Higher-Relaxivity Contrast Agent (CME Credit Available) Kuhn, M. Southern Illinois University School of Medicine, Grant, J.; Lee, E.; Lee, J.; Loh, C.; Kee, S. University of California- Springfield, IL Los Angeles Medical Center, Los Angeles, CA Address correspondence to M. Kuhn ([email protected]) Address correspondence to E. Lee ([email protected])

Objective: Higher doses of gadolinium-based contrast agents Background Information: Technological advances in the field of (GBCA) are often used for contrast-enhanced MR angiography interventional radiology (IR) have increased its role in the care of (CE-MRA) . Patients with stages 3-5 CKD undergoing contrast-en- oncology patients by offering targeted, effective treatment options hanced MRI are known to be at increased risk for the develop- for a wide range of cancers . In this review, the varied oncology ment of nephrogenic systemic fibrosis (NSF), a risk that increases armamentariums of IR will be presented along with procedure with higher GBCM doses or repeated GBCM exposures [1-2] . indications, images, and efficacies as indicated by recent studies . Herein we review information on the application of a higher relaxivity GBCA for low dose CE-MRA . Educational Goals/Teaching Points: The goals are to provide a complete review of the different armamentariums of interven- Materials and Methods: Eighty-seven subjects were studied in tional oncology and to present a pictorial review of various pres- six intraindividual crossover studies comparing gadobenate entations of tumors treated with these interventional oncology dimeglumine (Gd-BOPTA) to conventional GBCA for CE-MRA . In techniques . four studies equal 0 .1 mmol/kg doses of Gd-BOPTA and gado- pentetate dimeglumine (Gd-DTPA) were compared for MR angi- Key Anatomic/Physiologic Issues and Imaging Findings/ ography (MRA) of the renal arteries (n=10), peripheral vessels Techniques: The exhibit will include a background review on (n=14), pelvic vessels (n=5), and supra-aortic vessels (n=12) . In interventional oncology; a review of various tumor ablation meth- two studies 0 .1 mmol/kg Gd-BOPTA was compared to 0 .2 mmol/ ods (RFA, Cryo, HIFU, Microwave, IRE); a review of available tran- kg Gd-DTPA for MRA of the carotid arteries (n=12) or renal arter- sarterial chemoembolization (TACE) agents (embolic agents, ies (b=34) . Contrast enhancement was evaluated in a blinded chemotherapeutic agents, radioembolization), and a pictorial manner using both qualitative and quantitative metrics . review of various imaging presentations (CT/MR/ultrasound/ang- iography) of tumors treated with interventional oncology tech- Results: In MRA renal arteries greater (p<0 .05) vascular niques . enhancement (signal peak duration, maximum signal intensity [SI], and AUC) was observed for Gd-BOPTA vs . Gd-DTPA at 0 .1 Conclusion: After reviewing this educational exhibit, radiologists mmol/kg [3] . In peripheral MRA postcontrast SI was higher after should gain a basic knowledge on the various armamentariums Gd-BOPTA than Gd-DTPA from the aorta to the tibial arteries, with of interventional oncology; recognize different imaging presenta- better performance at lower levels [4] . In pelvic vessels tions of tumors that can be treated with these techniques, and Gd-BOPTA yielded higher (p<0 .02) SNR and CNR than Gd-DTPA recommend to clinicians appropriate and available methods for and better delineation of small vessels [5] . In supra-aortic MRA, optimal patient management . vessel delineation was higher (p=0 .005) and relative CNR great- er (p=0 .021) after Gd-BOPTA vs Gd-DTPA [6] . Two studies com- pared 0 1. mmol/kg Gd-BOPTA to 0 2. mmol/kg Gd-DTPA . In the E537. Embolization of Iatrogenic Hemorrhage carotid arteries, higher SI and CNR was seen with English, B.; Wright, K.; Ray, C. University of Colorado, Golden, CO Gd-BOPTA despite the lower dose [7] . In renal arteries, equiva- Address correspondence to C. Ray ([email protected]) lent SNR and CNR were seen for Gd-BOPTA and 2X Gd-DTPA with a greater increase seen at lower aortic levels with Background Information: Hemorrhage caused by medical pro- Gd-BOPTA [8] . cedures may be uncontrollable . In such settings, embolization techniques may represent the least invasive and most effective Conclusion: Intraindividual CE-MRA studies in various vascular form of therapy . Familiarity with specific clinical and technical territories show that MR angiography may be performed with a considerations is vital to practitioners treating such injuries with single dose of the higher-relaxivity Gd-BOPTA, potentially limiting endovascular techniques . patient exposure to GBCA . References: 1.Broome, AJR 2007;188:586–592 . 2 . Educational Goals/Teaching Points: The goals are to present a Sadowski, Radiol. 2007;243:148–157. 3. Knopp, Inv Radl. brief literature review on the current state of embolization thera- 2002;37:706–715 . 4 . Knopp, JMRI . 2003; 17:694–702 .5 . Herborn, py for bleeding caused by medical procedures; to discuss clinical Inv Rad. 2003;38:27–33 . 6 . Bueltmann, Inv Rad. 2008;43:695– presentations that may be specific to this patient population; to 702 . 7 . Pediconi, Radiol Med. 2003;106:87–93 . 8 . Prokop, Radiol. present endovascular treatment algorithms for patients present- 2005;234:399–408 . ing with postprocedural hemorrhage, and to present manage- ment techniques for this patient population through the use of case-based examples .

Key Anatomic/Physiologic Issues and Imaging Findings/ Techniques: Indications for embolization include situations when conservative management fails, challenging surgical scenarios (certain postradiation or postsurgical settings), or for preoperative

355 El e c t r o n i c Ex h i b i t s : Interventional stabilization of an unstable patient . Prior to embolization, collat- E539. Volume Visualization of CT Data: Review of Rendering eral vasculature must be assessed via a more central angiogram, Techniques: A Practical Approach to determine the presence of collateral vessels and/or the ability Fishman, E.; Horton, K.; Johnson, P. Johns Hopkins Hospital, to sacrifice downstream supply . The ideal embolization technique Owings Mills, MD allows for accurate delivery to the target, with a low risk of injury Address correspondence to E. Fishman ([email protected]) to normal structures . The level of desired occlusion, permanency and ability to sacrifice downstream supply determine the size Background Information: With the advent of 64 slice MDCT the and type of specific embolic agent . use of 3D imaging and other postprocessing techniques has moved from an abstract application to a mainstream application . Conclusion: Embolization therapy represents an important man- Routine CT datasets of 1,000-2,000 slices can not be viewed with agement technique used in the treatment of postprocedural an axial scroll technique in an efficient manner even if they could hemorrhage . limit the information that can be extracted from an isotrophic dataset . The use of postprocessing techniques including multipla- nar reconstruction (MPR), volume rendering (VRT) and maximum E538. Difficult Access in Intervention: Tips and Tools intensity projection (MIP) techniques are commonly used for Midia, M.; Kirby, J.; Chhibber, S.; Vora, P. McMaster University “visualization” of CT data sets today . Despite their availablity the Hospital, Burlington, Canada use of these techniques is sporadic in part because users are not Address correspondence to M. Midia ([email protected]) aware of the advantages and disadvantages of each technique . This exhibit will define the advantages and disadvantages of each Background Information: Difficult access often challenges inter- technique focusing on specific applications and clinical practice . ventional radiologist in performing a variety of procedures (biop- A scheme for implementation of these techniques into daily prac- sy, drainage, ablation, etc) . Here we offer a systematic approach tice will be presented . to different tools and techniques that could be used to address difficult cases and avoid complications . Educational Goals/Teaching Points: The goals are to provide an outline of the advantages of MPR and 3D imaging in clinical Educational Goals/Teaching Points: The tools and techniques practice of CT in the abdomen; provide an understanding of how available could be categorized into the following: a) patient MPR and curved planar reconstruction techniques are used and adjustment and manipulation, b) guiding tool selection, optimiza- their advantages and limitations; provide an understanding of the tion and multimodality approach, c) ancillary techniques to alter advantages of volume rendering technique for 3D postprocessing and create access route, and d) tools modification and selection . as well as some of its limitations; discuss the understand the advantages of maximum intensity technique for 3D postprocess- Key Anatomic/Physiologic Issues and Imaging Findings/ ing as well as some of its limitations, and describe specific appli- Techniques: In approaching each case identifying the location of cations where postprocessing is critical for the correct diagnosis the target, and nearby vital organs are key initial steps in plan- and staging of disease . ning a procedure . Subsequently determining a suitable operating window and reliable guiding tool/s are essential . Finally an Key Anatomic/Physiologic Issues and Imaging Findings/ appropriate set of tools could be used to complete the task at Techniques: The exhibit will include 3D postprocessing tech- hand . niques; the role of volume visualization; the advantages and dis- advantages of MPR,VRT and MIP techniques, and analysis of vol- Conclusion: Here we provide an up to date comprehensive list ume CT datasets . of armamentarium in a systematic fashion that is applicable to day to day practice of every radiologist performing imaging guid- Conclusion: The key to using 64 slice MDCT (and beyond) is the ed percutaneous procedures . integration of postprocessing techniques including MPR,VRTand MIP techniques into the clinical workflow . This exhibit provides a “how-to” approach to this issue .

356

ARRS’ Online Community Focusing on Women’s Imaging O ers Information Unavailable Elsewhere WomensImagingOnline.org is a unique Web-based meeting place for radiologists, radiologic technologists, referring physicians, and patients providing imaging services for women. Features of the online community include:  Educational programs on breast imaging, pelvic imaging, and more  Women’s imaging job and meeting listings  Interviews with experts in the eld  Behind-the-scenes interviews with AJR authors  Patient information resources you can use in your practice  Practice management tools for women’s imaging professionals  Literature reviews from across medicine relevant to women’s imaging  Original articles and reviews authored by women’s imaging experts This service is updated daily, so check back regularly to ensure you are getting the latest information to enhance patient care in women’s imaging. www.WomensImagingOnline.org

www.arrs.org PB09