title: Contrast-enhanced magnetic resonance angiography in the evaluation of peripheral bypass grafts.
abstract: The aim of this study was to determine the potential of contrast-enhanced magnetic resonance (MR) angiography in the evaluation of peripheral bypass grafts. Digital subtraction angiography (DSA) served as a standard of reference. Thirty-five patients with previous bypass graft surgery underwent DSA and contrast-enhanced MR angiography within 2 weeks. MR angiography was performed using a three-dimensional fast gradient-echo sequence after administration of gadopentetate dimeglumine. Every leg was divided into 11 segments and scored in five categories of stenosis. MR angiography findings were compared with those of DSA. A total of 38 bypass grafts and 454 segments in 27 patients were included in the evaluation. In 33 (87%) bypass grafts stenosis grading with both methods corresponded, and in 5 (13%) cases stenosis was overestimated on MR angiography. Agreement in detection of hemodynamically significant stenosis (stenosis =50%) was 94.7% with a sensitivity of 100% and a specificity of 91.3%. In 340 (83.0%) vascular segments there was conformity in graduation, in 69 (16.88%), there was a difference of one or more grades on MR angiograms. Forty-four segments (9.6%) were not assessable due to technical limitations. Contrast-enhanced MR angiography is an useful noninvasive tool in the detection of failing peripheral vascular bypass grafts.
authors.affiliation: Department of Angiography and Interventional Radiology, University of Vienna, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Loewe
authors.forename: M
authors.initials: M
authors.lastname: Cejna
authors.forename: J
authors.initials: J
authors.lastname: Lammer
authors.forename: S A
authors.initials: SA
authors.lastname: Thurnher
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D001807:Blood Vessel Prosthesis; D003251:Constriction, Pathologic / Q000175:diagnosis; D003287:Contrast Media; D005260:Female; D005263:Femoral Artery / Q000473:pathology; D019786:Gadolinium DTPA; D006083:Graft Occlusion, Vascular / Q000175:diagnosis; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007083:Iliac Artery / Q000473:pathology; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007866:Leg / Q000098:blood supply*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000601:surgery; D011150:Popliteal Artery / Q000473:pathology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014654:Vascular Patency
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA