Radiologic evaluation of penetrating aortic atherosclerotic ulcer.

Patients with penetrating atherosclerotic ulcers of the aorta present with back or chest pain that mimics classic aortic dissection. The pathologic findings, however, are distinctly different from those of aortic dissection in that an atherosclerotic lesion with ulceration penetrates into the internal elastic lamina, allowing hematoma formation within the media of the aortic wall. This may lead to false aneurysm or, rarely, transmural rupture of the aorta. Imaging findings of penetrating aortic atherosclerotic ulcers are also different from those of classic aortic dissection. We have found computed tomography to be especially useful in differentiating between these entities and present several illustrative cases.