Aortic source for distal embolism

The patient presented with embolic occlusion of the right common femoral artery presumably from the aorta. In the CT image, the aorta is ectatic with irregular intraluminal thrombus. The selected bone windows help to differentiate the contrast bolus from the calcium in the aortic wall. While the aorta in this segment measures 3.4 cm, the more proximal infrarenal aorta was normal in size at 2.8 cm.