Preoperative evaluation of abdominal aortic aneurysms by computed tomography

A prospective, preoperative study was conducted of 50 electively repaired abdominal aortic aneurysms comparing the CT and angiographic findings with those described at surgery. CT demonstrated all 50 aneurysms and correctly identified their proximal extent in relation to the takeoff of the renal arteries in 47 patients (94%), while angiography detected 48 aneurysms (96%) and their correct relation to the renal arteries in all (100%). CT correctly identified 40 (98%) of 41 patients with two renal arteries, but only two (29%) of seven with three and none of two patients with four arteries. Common iliac artery involvement or lack thereof was accurately predicted in 42 (84%) of the 50 patients and internal iliac artery aneurysms found in one (33%) of three patients. It was concluded that CT is not sufficiently accurate for documenting location and patency of the renal arteries to allow its routine substitution for angiography in patients undergoing preoperative assessment of abdominal aortic aneurysms.