AAA may be diagnosed by a variety of methods, including physical examination (presenting as a palpable pulsatile tumour), ultrasonography, CT, MRI, angiography or radiography. CT images are three-dimensional images of the inside of the body that are generated from a large series of two-dimensional X-ray images, which are taken around a rotational axis and are especially useful for preoperative clarification of detailed anatomy and endovascular repair eligibilities. MRI, which uses the property of nuclear magnetic resonance to image nuclei of atoms inside the body and angiography, which visualises the inside of blood vessels by injecting a contrast agent into the blood vessel and imaging it using X-ray based techniques, are both more expensive than the other methods. AAA imaging by radiography is only possible in case of calcification of the aneurysm wall, which occurs in less than 50% of all AAAs {27}.

For AAA screening and determination of AAA-diameter, ultrasonography has been established as the gold standard. This technique is non-invasive, sensitive, portable and inexpensive. However, applicability may be reduced in obese people. Even if long term biological effects of diagnostic ultrasound exposure cannot be determined today {28}, most medical doctors feel that for the patient the benefits of correctly performed ultrasound outweigh the risks {29}. Nevertheless, investigations should be restricted to clearly indicated diagnostic questions. Scanning time should be held as short as possible and power should be set as low as possible, following the ALARA (As Low As Reasonably Achievable) principle {30}.

It has been proposed that population-based systematic screening programmes for AAA by ultrasonography offer a clear benefit over harm and are ethically justified as long as people are given adequate information {31}.

Ultrasonography is applicable for a wide spectrum of medical diagnostic assessments, including imaging of the heart muscle and the cardiac valves, prenatal diagnostics and gastroenterological investigations. With respect to the vascular system, colour-coded duplex sonography is applied, not only to assess potential vascular dilation, stenosis or occlusions of the carotid artery, the abdominal aortic artery and the peripheral arteries of the upper and lower extremities, but also enables detection of venous diseases, including varicosities and deep venous thrombosis. Ultrasound waves also may be used for therapeutic reasons. {32}