Sealed rupture of abdominal aortic aneurysms: CT features in 6 patients and a review of the literature.

PURPOSE: To assess the CT features of sealed rupture of abdominal aortic aneurysm. PATIENTS AND METHODS: We reviewed the CT scans of six index cases obtained over a 3 year period with a sealed rupture of an abdominal aortic aneurysm and those reported in the literature over a 21 year period. CT scans were reviewed for aneurysm size, the presence of a draped aorta and adjacent vertebral erosion. A group of consecutive patients with non-ruptured abdominal aortic aneurysm, referred for endovascular aneurysm repair during the same 3 year period constituted the control group. RESULTS: In the study group of 31 patients the mean size of the aneurysm was 6.24 +/- 2.01 cm, compared to 6.01 +/- 0.99 cm in the control group, without statistically significant difference (t = 0.75, df = 97, P = 0.46). A draped aorta was detected in all patients with a sealed rupture. Vertebral erosion was present in all our six, but mentioned in only 14 of the cases reported. CONCLUSION: A sealed rupture of an abdominal aortic aneurysm can occur in relatively small aneurysms. A draped aorta and adjacent vertebral erosion are characteristic CT signs of such a rupture.