Idiopathic aneurysmal dilatation of the ascending aorta on CT scan

An MIP CT scan (A) in a 42-year-old man shows idiopathic dilatation of the ascending aorta (arrowhead). Image B is a sagittal reconstruction of a CT in a 40-year-old man and shows calcification (arrowhead) in a fusiform ascending aortic aneurysm (asterisk). Cystic medial necrosis is a possible contributing etiology for the aneurysmal changes of the ascending aorta in both cases.