Figure 14c. (a-d) Diagrams illustrate the four stages in the formation of a penetrating atherosclerotic ulcer: aortic atheroma (a), benign intimal plaque ulceration contained in the intima (b), medial hematoma with potential adventitial false aneurysm (c), and transmural rupture (d). (e) Photograph of an autopsy specimen shows severe atherosclerotic changes in the descending aorta, with ulceration of the media (arrows) and IMH (*). Scale is in centimeters.