Aortic aneurysm is commonly defined as a localized, permanent aortic dilation diameter of 50% or greater than normal, and is contained by all the layers of the normal aortic wall. Degeneration of the elastic media is the most common biologic cause of aneurysm formation, but congenital syndromes such as bicuspid aorta disease, Marfan syndrome, Ehlers–Danlos syndrome and Loeys–Dietz syndrome, as well as infectious and noninfectious inflammatory syndromes are additional causes. Ascending aortic aneurysms are commonly asymptomatic, and are frequently discovered incidentally on radiographic studies. The advancement of echocardiography, computed tomography (CT), and magnetic resonance imaging (MRI) have allowed for many options for radiologic assessment.
