Figure 36 Figure 36 is an example of lumenography with MRA, which shows a beautiful example of a penetrating ulcer in the descending thoracic aorta. It is crescentic. It is not sharp. There is no mass effect on the aorta. Therefore, this is an intramural hematoma involving the ascending and descending aorta.
Intramural hematoma is simply blood within the aortic media.
It may be helpful to classify each hematoma as primary or secondary. There is no intimal flap. It is usually diffuse, because atherosclerosis is an inflammatory disease and these patients usually do not have atherosclerosis. These are usually younger patients who present with diffuse intramural hematoma. Figure 37 Figure 37 shows what the aorta looks like in the subacute stage of methemoglobin.