Three-dimensional Reconstructed Contrast–enhanced MR Angiography for Internal Iliac Artery Branch Visualization before Uterine Artery Embolization Nagy N.N. Naguib, MSc,* Nour-Eldin A. Nour-Eldin, MSc,* Renate M. Hammerstingl, MD, Thomas Lehnert, MD, Julius Floeter, MD, Stefan Zangos, MD, and Thomas J. Vogl, MD PURPOSE: To evaluate the feasibility of three-dimensional (3D) reconstructed contrast-enhanced (CE) magnetic resonance (MR) angiography in mapping the pelvic arteries in women before uterine artery embolization (UAE). MATERIALS AND METHODS: CE MR angiography studies before UAE in 49 women (age range, 38–57 years; mean, y ؎ 4.7 [SD]) who underwent UAE for uterine leiomyomas between February 2005 and February 2007 were 47.04 retrospectively evaluated by two radiologists in consensus. Studies were performed on a 1.5-T MR unit with a 3D fast low-angle shot sequence in the coronal direction. Reconstruction was performed with 3D computed tomographic angiography reconstruction software. RESULTS: In the current study, 98 internal iliac arteries (IIAs) from 49 women were studied. The superior and inferior the lateral sacral artery in 86 cases (88%), the iliolumbar ,(%100 ;98 ؍ gluteal arteries were visualized in all cases (N artery in 84 (86%), the obturator artery in 81 (83%), the internal pudendal artery in 96 (98%), and the uterine artery in 95 (97%). The superior vesical and middle rectal arteries were seen in 21 (21%) and 11 (11%) cases, respectively. The mean length of the uterine artery was 12.56 cm (range, 4.6–22.2 cm), and it showed the longest traceable length among all branches. The uterine artery showed five patterns of origin. The superior gluteal artery showed constant origin from the posterior division of the IIA, whereas the iliolumbar and obturator arteries showed the most variations in origin. CONCLUSIONS: Three-dimensional reconstructed CE MR angiography can detect most branches of the IIA in addition to their point of origin. Therefore, it can be used as a mapping tool of the pelvic arterial tree before UAE. J Vasc Interv Radiol 2008; 19:1569–1575 Abbreviations: CE ϭ contrast-enhanced, IIA ϭ internal iliac artery, 3D ϭ three-dimensional, UAE ϭ uterine artery embolization THE internal iliac artery (IIA) can be male subjects, it gains its importance Uterine leiomyomas (or fibroid tu- regarded as a silent artery in women. In from the possibility of being a cause of mors) are the most common pelvic tu- vasculogenic impotence (1). Apart from mors, with an overall incidence of this, its disease entities usually—but not 35%–50% among all women (8). Uter- From the Institute for Diagnostic and Interventional always (2)—remain asymptomatic ex- ine artery embolization (UAE) is a Radiology, Johann Wolfgang Goethe University cept when the IIA is acutely occluded or minimally invasive therapy for uterine Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am an aneurysm develops (which might leiomyomas that represents an alter- Main, Germany. Received March 3, 2008; final revi- sion received and accepted August 8, 2008. Address present with pelvic mass, pain, and/or native to hysterectomy and myomec- correspondence to N.N.N.N.; E-mail: nagynnn@ sudden rupture). This probably results tomy (9), or it can be performed before yahoo.com from the presence of an excellent net- myomectomy as a part of combined *Drs. Naguib and Nour-Eldin contributed equally to work of collateral vessels in the pelvis therapy aimed at reducing the bleed- this work. that can be used in case of stenosis or ing during multiple myomectomy op- obstruction. Even IIA occlusion can be eration. During the past decade, UAE None of the authors have identified a conflict of interest. used as a treatment for some gyneco- has been established as a safe and ef- logic conditions (3,4) or as a part of en- fective first-line therapy for the treat- © SIR, 2008 dovascular repair of abdominal aortic ment of symptomatic leiomyomas in DOI: 10.1016/j.jvir.2008.08.012 aneurysms (5–7). premenopausal women (10). How- 1569 1570 • Three-dimensional Reconstructed MR Angiography before UAE November 2008 JVIR ever, the pelvic arterial anatomy is history, and physical examination. All terial and venous phases. The unen- among the most complex in the body. patients expressed a desire to avoid hanced examination was performed to Identifying and catheterizing the cor- surgical treatments and were exten- permit image subtraction of the unen- rect artery for UAE can be extraordi- sively counseled as to the known risks hanced images from the CE images narily difficult, even for a physician and benefits of UAE and alternative after the examination. The subtracted who routinely does so (11). Magnetic treatments. images obtained in the arterial phase resonance (MR) imaging is increas- were loaded into the multislice CT ingly being used to evaluate patients MR Imaging and Image console (Somatom Sensation; Sie- before UAE because of its precision in Reconstruction Technique mens), and a 3D reconstructed view of helping determine the size and loca- the pelvic arterial tree was obtained tion of uterine leiomyomas and help- CE MR angiography was per- with use of the same software used for ing exclude other diseases (12,13). formed with a 1.5-T MR imaging sys- 3D reconstruction of the CT angiogra- Because of the increased popularity tem (Magnetom Symphony; Siemens, phy images (Syngo Vessel View Ap- of pelvic interventional procedures— Erlangen, Germany). A body-array plication; Siemens). This allowed the with UAE currently being the most coil was used to cover the volume of free rotation of the 3D model in all common—and because of the lack of interest. First, gradient-echo magneti- directions to aid correct judgment of sufficient data in the medical literature zation-transfer scout images (echo/ the course of the vessels in all direc- regarding the study of the IIA with repetition times, 5/15 msec; 40° flip an- tions. MR angiography, even routine angio- gle; slice thickness, 10 mm; matrix, 128 ϫ graphic studies are seen as insuffi- 256, 40-cm field of view) were ob- Image Evaluations cient. The present study was con- tained in three planes. Second, T2- ducted with the aim of evaluating the weighted single-shot turbo spin-echo All MR images were assessed in feasibility of 3D reconstructed con- MR images (echo/repetition times, 95/ consensus by two senior radiologists trast-enhanced (CE) MR angiography 4,000 msec; 150° flip angle, slice thick- with more than 5 and 15 years, respec- in visualizing the different branches of ness, 6 mm; matrix, 128 ϫ 256; 35-cm tively, of experience in the field of pel- the IIA and to study the anatomic vari- field of view) were obtained in the sag- vic MR imaging, who were blinded to ations in origin of the different branches ittal direction. Before application of the the conventional angiographic images of the IIA in women, with special em- contrast agent, an unenhanced 3D fast of the patients at the time of evalua- phasis on the uterine artery as the target low-angle shot sequence (echo/repeti- tion. For each study, nine branches of artery in UAE. tion times, 1.28/3.66 msec; 25° flip an- the IIA (superior and inferior gluteal, gle, slice thickness, 1.2 mm; matrix, 128 internal pudendal, iliolumbar, lateral ϫ MATERIALS AND METHODS 512, 40-cm field of view) in a coronal sacral, obturator, uterine, superior slice orientation was performed during vesical, and middle rectal arteries) The study was approved by the in- the end-inspiratory phase. The study were evaluated on each side. Branches stitutional review board. Informed should extend anteriorly to include the were identified based on their course, consent was obtained from all patients external iliac artery and its inferior epi- with continual rotation of the 3D re- included in the study after a full ex- gastric branch and should extend poste- constructed model of the pelvic arte- planation of the procedure. Preembo- riorly to include the inferior gluteal and rial tree in all directions. Each branch lization CE MR angiographic studies internal pudendal arteries at the point was evaluated for its visualization, from 49 women who underwent UAE where they escape from the pelvis be- length, and site of origin. For visual- for uterine leiomyomas during the tween the piriforms and coccygeus ization, a three-grade scoring system time period from February 2005 until muscles (this is the most posterior point was adopted: a score of 0 indicated February 2007 (age range, 38–57 years; along their course). For the determina- that the artery was not seen, inter- mean, 47.04 y Ϯ 4.7 [SD]) were retro- tion of the travel time for contrast mate- rupted, or its origin could not be iden- spectively evaluated by two radiolo- rial from the injection site to the pelvic tified; a score of 1 indicated that the gists. All patients underwent MR im- vessels, a test bolus technique was used. artery was faintly seen but could be aging, including CE MR angiography, Two milliliters of gadopentetate dime- traced and had no missing segments as a part of the preinterventional glumine (Magnevist; Schering, Berlin, until its first branch arose; and a score workup. Germany) were used for this purpose. of 2 indicated that the artery was Patients’ renal function was checked clearly seen. Regarding the lengths of Patient Selection before contrast agent administration. the branches, measurement started Based on the circulation time, contrast from their point of origin until their All patients self-reported symptom- agent was intravenously injected (0.1 first branch arose or they were no atic uterine leiomyomas. Symptoms mmol/kg body weight followed by 20 more visualized. were mainly in the form of abnormal mL normal saline solution) with an uterine bleeding, bulk-related symp- MR-compatible power injector (Spec- Data Collection and Statistical toms, pain, or a combination of symp- tris; Medrad, Pittsburgh, Pennsylva- Analysis toms.