Computed tomography of life-threatening complications of abdominal aortic aneurysm. The disrupted aortic wall.

A localized disruption of the conspicuity of the wall of the aorta was noted on intravenous contrast-enhanced computed tomography (CT) scans of ten patients with ruptured abdominal aortic aneurysm (n = 6) or aortoenteric fistula (n = 4). Subsequently, we reviewed 84 scans of patients with uncomplicated aneurysm (n = 70) or aneurysm graft repair (n = 14) to determine if a disrupted wall has diagnostic implications. In this control group, the wall of the aneurysm was conspicuous throughout in 95% of 64 patients who received iodinated contrast material intravenously and in 55% of 20 patients who did not. In the proper clinical setting, CT scans performed with intravenous administration of iodinated contrast material can provide direct evidence of disruption of the wall of an abdominal aortic aneurysm. In selected cases, this may be important for the diagnosis of rupture. Disrupted conspicuity of the wall, in combination with effacement of the fat plane between an aneurysm and the juxtaposed intestine, increases the accuracy of CT for the diagnosis of aortoenteric fistula.