Analysis of initial CT findings after endovascular repair of abdominal aortic aneurysm

PURPOSE: To determine the spectrum and frequency of specific computed tomog raphic (CT) findings in the acute period after endovascular repair of abdom inal aortic aneurysm (AAA). MATERIALS AND METHODS: CT images obtained 1-3 days after endograft placemen t were evaluated in 88 patients. The images were analyzed for stent positio n, appearance of endograft components, perigraft leak, and postoperative fi ndings including air and acute thrombus within the aneurysm and air surroun ding the femoral-femoral bypass graft. Findings that could be misinterprete d as perigraft leak were evaluated. RESULTS: Fifteen (17%) of 88 patients had perigraft leak in the acute posto perative period. The bare segment of the proximal self-expanding stent cove red one or both renal arteries in 54 (61%) patients. One patient had CT evi dence of renovascular compromise. Postoperative air was within the aneurysm al sac in 51 (58%) patients and surrounded the femoral-femoral bypass graft in 67 (94%) of 71 patients in whom the grafts were evaluated with CT. Mott led attenuation within the aneurysmal sac was seen in 50 (57%) patients. Fo rty-six (52%) patients had calcifications within longstanding thrombus. In 31 (35%) patients, findings that could have been misinterpreted as perigraf t leak were identified. CONCLUSION: Accurate analysis of CT findings after endovascular AAA repair requires careful review of all available CT images (preprocedural and pre- and postcontrast) and clear understanding of specific stent-graft component s and placement.