Most abdominal aortic aneurysms will not show up on a plain x-ray.
In fact, these may not even show up on a fluoroscopic angiogram
(an xray taken with special dye that shows the outline of blood flow in an artery). The best screening test is a duplex ultrasound of the abdomen. Infrequently, an aneurysm
will be calcified and be seen on plain x-ray -- but many more will be missed on x-ray alone!