Thoracic Aortic Aneurysms, Fistula, and Thrombus

Thoracic aortic aneurysms (TAAs) are abnormal dilatation occurring in the thoracic aorta. They can be classified according to location, morphology, and etiology. TAAs can be divided into true aneurysms and false aneurysms (also called pseudoaneurysms). True aneurysms are usually associated with fusiform dilatation of the aorta and most commonly due to atherosclerosis. False aneurysms are typically saccular with a narrow neck and most commonly due to trauma, penetrating atherosclerotic ulcers, or infections (mycotic aneurysm). Atherosclerosis, genetic causes, aortitis, trauma, and dissection can be the causes of TAAs. MDCT allows the evaluation of TAAs in terms of morphologic features, extent, and signs of instability or impending rupture. Acute aortic thrombosis and aortic fistula with esophagus or bronchi are rare but life-threatening complications of aortic disease. Imaging findings may be subtle.