Which imaging study is preferred for diagnosing a suspected abdominal aortic aneurysm?

When it comes to diagnosing a suspected abdominal aortic aneurysm (AAA), an ultrasound is often the preferred initial imaging study. This is primarily due to its accessibility, speed, and the fact that it does not involve radiation exposure. Ultrasound is particularly effective for visualizing the aorta and can help assess the size and presence of an aneurysm.

Additionally, ultrasound is highly sensitive for detecting AAA and can be performed quickly, making it ideal for urgent situations where a rupture is suspected. It can also help in following the size of known aneurysms over time. While CT scans are very accurate and may be used subsequently to provide more detailed information about the aneurysm's extent, ultrasound serves as the first-line tool in many settings for its practicality and effectiveness.

In contrast, X-rays are generally not useful for this purpose, as they do not provide the necessary detail about the aorta or the aneurysm. MRI can provide excellent images but is less commonly used for this diagnosis due to higher costs, longer waiting times, and the need for specific conditions in many cases. Therefore, ultrasound's benefits make it the preferred choice for diagnosing a suspected abdominal aortic aneurysm.