Ultrasound screening for abdominal aortic aneurysm. Close-up of gel being applied to an ultrasound transducer. Ultrasound scans use reflected high-frequency sound waves to construct a picture of internal body organs. The gel aids transmission of the sound waves. This transducer will be used to scan a male patient's abdomen to assess the health of the abdominal section of his aorta, and whether an abdominal aortic aneurysm is present. The aorta is the body's main artery. It arches over the heart and descends to the abdomen. An aneurysm is a weakening of the walls of a blood vessel, leading to swelling and rupture. In the aorta, such rupturing is swiftly fatal. If the condition is detected before rupture, surgery is needed to repair the aorta and implant a stent to strengthen its walls.