Abdominal aortic aneurysm: pictorial review of common appearances and complications.

Abdominal aortic aneurysms (AAAs) are defined as focal dilatations of the abdominal aorta that are 50% greater than the proximal normal segment or when it is more than 3 cm in maximum diameter. The early diagnosis and treatment is very important to prevent catastrophic complications. Due to its ability to assess the peri-aortic soft tissue and the exact extension of aneurysm, as well as its excellent vascular opacification and multiplanar reconstruction capabilities, computed tomography angiography (CTA) has become an integral part of the evaluation of AAA and has virtually replaced conventional angiography for the evaluation of AAA. Knowledge of the characteristic imaging features of AAA is essential for the prompt diagnosis of life-threatening complications. In this pictorial essay, we will discuss the CTA findings in AAA and its complications including rupture, infection, aorto-enteric fistula and aorto-caval fistula.