EVALUATION OF ABDOMINAL AORTIC-ANEURYSM FOR STENT-GRAFT PLACEMENT - COMPARISON OF GADOLINIUM-ENHANCED MR-ANGIOGRAPHY VERSUS HELICAL CT ANGIOGRAPHY AND DIGITAL SUBTRACTION ANGIOGRAPHY

PURPOSE: To determine whether magnetic resonance (MR) angiography can be used alone to evaluate abdominal aortic aneurysms (AAAs) for endova scular placement of stent grafts. MATERIALS AND METHODS: Sixty-one pat ients with AAAs underwent gadolinium-enhanced MR angiography of the ab dominal aorta and pelvic arteries. Measurements of the size and extent of the AAAs were compared with helical computed tomographic (CT) and digital subtraction angiographic measurements; 95% confidence interval s for the differences in the means were determined. RESULTS: Because o f the larger field of view, MR angiography was superior to CT angiogra phy in assessing visceral iliac artery disease. Both modalities were e qual in evaluating the proximal extent of the AAA (mean difference, -0 .16 mm; 95% CI, -0.31, 0.64) and in measuring all aortic dimensions (e g, mean difference in the proximal neck diameter, -0.74 mm; 95% CI, -0 .98, -0.49). MR angiography was inferior to CT angiography in depictin g accessory renal arteries (seven of 12) and in grading renal artery s tenoses (sensitivity, 100% [95% CI, 0.90, 1.00]; specificity, 84% [95% CI, 0.74, 0.91]). CONCLUSION: Gadolinium-enhanced MR angiography is a fast, reliable means of providing all the information relevant to the preoperative assessment of endovascular aortic stent-graft placement.