How is an abdominal aortic aneurysm primarily diagnosed?

An abdominal aortic aneurysm (AAA) is primarily diagnosed using CT A/P with intravenous contrast dye because this imaging modality provides detailed visualization of the aorta's structure. CT scans can accurately measure the size of the aneurysm, assess its extent, and evaluate any potential complications such as rupture or dissection. The use of contrast dye enhances the images, allowing for better differentiation between the aneurysm and surrounding tissues, which is crucial for effective diagnosis and subsequent management.

Other methods, like physical examination, may suggest the presence of an AAA through findings such as a palpable mass in the abdomen, but these indicators are not definitive. Ultrasound can also be employed, particularly in specific contexts like monitoring known cases; however, it lacks the detailed anatomical information provided by a CT scan. In summary, the precision and clarity offered by a CT scan with contrast make it the gold standard for diagnosing an abdominal aortic aneurysm.