ISSN: 2165-3259 JAOCR Official Journal of the American Osteopathic College of Radiology BODY IMAGING Guest Editor: Rocky C. Saenz, D.O. Editor-in Chief: William T. O’Brien, Sr., D.O. October 2012, Vol. 1, Issue 4 JAOCR About the Journal Aims and Scope The Journal of the American Osteopathic College of Radiology (JAOCR) is designed to provide praccal up‐to‐ date reviews of crical topics in radiology for praccing radiologists and radiology trainees. Each quarterly issue covers a parcular radiology subspecialty and is composed of high quality review arcles and case reports that highlight differenal diagnoses and important teaching points. Access to Articles All articles published in the JAOCR are open access online. Subscriptions to the journal are not required to view or download articles. Reprints are not available. Copyrights Materials published in the JAOCR are protected by copyright. No part of this publication may be reproduced without written permission from the AOCR. Guide for Authors Submissions for the JAOCR are by invitation only. If you were invited to submit an article and have questions regarding the content or format, please contact the appropriate Guest Editor for that particular issue. Although contributions are invited, they are subject to peer review and inal acceptance. Editor‐in‐Chief William T. O’Brien, Sr., D.O. San Antonio, TX Design Editor Jessica Roberts Communications Director, AOCR Managing Editor Tammam Beydoun, D.O. Farmington Hills, MI Editorial Board Susann Schetter, D.O. Daniel J. Abbis, D.O. Les R. Folio, D.O. Michael W. Keleher, D.O. Rocky Saenz, D.O. Kipp A. Van Camp, D.O. John Wherthey, D.O. J Am Osteopath Coll Radiol 2012; Vol. 1, Issue 4 Page i Table of Contents Body Imaging Editor: Rocky C. Saenz, D.O. Title/Author(s) Page No. From the Guest Editor 1 Review Arcles MRI of Benign Liver Lesions and Metastac Disease Characterizaon with Gadoxetate Disodium 2 Rocky C. Saenz, D.O. Pancreac Neoplasms 10 Ruedi Theoni, M.D. Gallbladder Masses: Mulmodality Approach to Differenal Diagnosis 22 Timothy McKnight, D.O., and Ankit Patel, D.O. Case Reports Cysc Right Lower Quadrant Mass 32 Tammam Beydoun, D.O., and Sharon Kreuer, D.O. Non‐Adnexal Cysc Pelvic Mass 35 Reehan M. Ali, D.O. Pancreac Mass 38 Rocky C. Saenz, D.O. JAOCR At the Viewbox Acute Necrozing Pancreas 41 Sharon Kreuer, D.O. Pneumatosis Intesnalis With Evidence of Portal Venous Gas 42 Mahew R. Tommack, D.O. Portal Vein Thrombosis 43 Reehan M. Ali, D.O., and Daniel J. Cranford, D.O. Page ii J Am Osteopath Coll Radiol 2012; Vol. 1, Issue 4 From the Guest Editor In This Issue Rocky C. Saenz, D.O. Radiology Residency Program Director, Botsford Hospital, Farmington Hills, MI As simple as it sounds, this phrase is The “Case Reports” and “Viewbox” especially true in the field of medicine arcles are also stellar. All were wrien and radiology. Lifelong learning is what by the Botsford Hospital Radiology all physicians are commied to. In Residents with the excepon of one. I order to achieve this, one must be authored a case report on granulocyte proacve which takes me and effort. sarcoma of the pancreas, which was a This includes reviewing the current case I saw in my recent pracce which literature and praccing cung edge turns out to be very unique case; radiology. With these wise words and Reehan Ali, D.O., authored a case thoughts in mind, I present to you this report on enteric duplicaon cyst; and wonderful, informave issue. Sharon Kreuer, D.O., and Tammam I feel honored to have been selected Beydoun, D.O., co‐authored a case by the JAOCR to be the Guest Editor of report on Mucocele of the appendix. its inaugural Body Imaging issue. To be The “Viewbox” arcles cover key entrusted with this important academic radiographic findings that are “can’t endeavor is a great honor. With such an miss” cases. These “Viewbox” arcles immense task, I have put together what include cases of pneumointesnalis by I believe is a great first Body Imaging Ma Tommack, D.O., portal vein issue. The review arcles include MRI of thrombosis by Reehan Ali, D.O., and the liver – with the ulizaon of necrozing pancreas by Sharon gadoxec disodium (Eovist) in parcular Kreuer, D.O. – reviewing benign lesions versus I would like to thank William O'Brien, metastac disease, which I authored. D.O., and the AOCR for giving me this The next review arcle covers opportunity. I would also like to thank pancreac lesions and is a very Dr. Paul LaCasse, D.O., Stephan Morse, comprehensive review wrien by Ruedi D.O., and Botsford Hospital’s F. Thoeni, M.D., my prior mentor and Department of Radiology (Including trainer from University of California, Radiology Technicians, Residents, and San Francisco. The final review arcle Aendings). Next, I give special thanks was wrien by Ankit Patel, D.O., and to all of the authors of this issue for Timothy McKnight, D.O., and covers agreeing to share their knowledge and gallbladder pathology. This arcle was hard work with us, and also for making wrien when Dr. Patel and Dr. all of the deadlines and pung‐up with McKnight were fellows at University of my endless trail of emails. Last and California, Irvine and Dartmouth, most importantly, I would like to thank respecvely. I believe these three my wife Blanca and sons Rocky, Russell, arcles will provide the reader with a Ronin, and Rex. Without my strong great foundaon and understanding of family support, I would not be able to pancreac pathology, gallbladder complete this academic project or any pathology, and the use of gadoxec of my other creave works. disodium in discriminang benign from malignant liver lesions. J Am Osteopath Coll Radiol 2012; Vol. 1, Issue 4 Page 1 MRI Liver, Saenz MRI of Benign Liver Lesions and Metastac Disease Characterizaon with Gadoxetate Disodium Rocky C. Saenz, D.O. Department of Diagnosc Radiology, Botsford Hospital, Farmington Hills, MI Introducon limitaons. The same restricons and precauons remain with gadoxetate disodium for nephrogenic Imaging characterizaon of liver lesions is of systemic fibrosis as with standard extracellular diagnosc importance with regard to its implicaons gadolinium products.2 on paent treatment. Ulizaon of dynamic MRI has Gadoxetate disodium is best ulized with dynamic, become a common pracce as an adjunct to dynamic gradient echo (GRE) T1 fat saturaon imaging. CT scanning. With the recent FDA approval of Opmally, arterial phase imaging, portal venous gadoxec disodium, this provides another avenue for imaging, and delayed imaging at 20 minutes should be evaluaon and characterizaon of indeterminate liver performed. Typically, liver lesions without hepatocytes lesions. Gadoxec acid was approved for use in the will not accumulate gadoxetate disodium on delayed United States by the FDA in 2008 for detecon and imaging. Therefore, they are hypointense relave to characterizaon of liver lesions in adults with known 1 the nave liver parenchyma on the hepatocyte phase. or suspected focal liver disease The purpose of this Since nearly all malignancies lack funconing arcle is to review the imaging findings ulizing hepatocytes, they will typically be hypointense on the gadoxec disodium with respect to benign liver lesions hepatocyte phase. The one excepon to this rule is and metastac disease. well‐differenated hepatocellular carcinoma, which demonstrates enhancement on the hepatocyte phase Gadoxetate Disodium secondary to residual funconing hepatocytes.4‐5 Pre‐ contrast imaging with T1‐weighted, T2‐weighted, and The advantage of ulizing gadoxetate disodium in‐phase and out‐of‐phase imaging are also beneficial comes from its added hepatocyte phase intracellular in characterizing liver lesions. imaging. The prior standard gadolinium agents only provide extracellular informaon with regards to indeterminate liver lesions. Gadoxec disodium with Hepac Cyst its addional hepatocyte phase has the ability to Hepac cysts are seen rounely on diagnosc provide more specific informaon of the hepatocyte imaging studies and usually do not pose a diagnosc funcon/content of an indeterminate liver lesion. dilemma. Histologically, hepac cysts are derived from Gadoxec disodium has two routes of eliminaon: biliary endothelium and contain serous fluid lined by a 2 renal and hepatobiliary. The eliminaon pathways single layer of epithelium.6 These benign lesions are 2 are equally distributed. Given its increased T1 more commonly seen in women and may be mulple shortening compared to tradional extracellular in number. Enes such as autosomal dominant gadolinium products, a lower dose of contrast is polycysc kidney disease or tuberous sclerosis have 2 required (0.1 mL per kilogram of body weight). The been known to present with innumerable hepac gadoxetate disodium is transported from the cysts. extracellular space to the intracellular space by ATP‐ CT and MRI imaging of hepac cysts are dependent organic anion transporng polypepde 1 3 complementary in that both modalies show similar (OATP1) and then excreted into the biliary tract. The findings. Cysts on CT and MRI do not demonstrate intracellular imaging (hepatocyte phase) is obtained 20 contrast enhancement. In addion, T1 and T2‐ minutes aer intravenous injecon. This hepatocyte 2 weighted MR images show the cysts to follow fluid phase lasts up to 120 minutes, which allows for signal. Hepatocyte phase imaging is usually not repeat acquisions on delayed phase imaging to needed in order to characterize these lesions; these correct for paent moon or other potenal technical Page 2 J Am Osteopath Coll Radiol 2012; Vol. 1, Issue 4 MRI Liver, Saenz Figure 1. Hepac Cyst. Mulple axial images demonstrate a Figure 2. Hemangioma. Mulple axial images demonstrate a small lesion in segment VII of the right lobe of the liver. The moderately‐sized lesion in segment IVa of the liver.