Unfortunely the symptoms of an abdominal aneurysm (AAA) are very rare. Most AAAs are asymptomatic, which leads to difficulty in their clinical diagnosis. Occasionally patients may describe a pulse or may palpate a pulsative mass in their abdomen. Most aneurysms that become symptomatic do so because of rupture or acute expansion.
Patients may experience the onset of abdominal or back pain that radiate into the flank or groin. Many aneurysms are detected by incidental abdominal imaging studies done for other reasons. It is very important to mention that 23% of the AAAs were not palpable enen when the diagnosis was known.
Clinical detection of the abdominal aneurysm by examination depends on the size, the obesity of the patient, the skill of the examiner and the focus of the examination.
A pooled analysis of the literature showed that with the physical examination alone the diagnosis is made in 50% of AAAs 4-4,9cm, 75% of AAAs 5cm or larger.(Rutherford 2005).
Several imaging modalities are available to confirm the diagnosis of the abdominal aneurysm. Ultrasonography is the least invasive and offers great accuracy. Ultrasonography cannot accurately determine the presence of the rupture and the upper extent of an AAA. Computer Tomography is more expensive than ultrasound, involves radiation and accuracy can be increased by using standarized techiques, electronic calipers and magnification. Compared with CT, ultrasound seems to underestimate the diameter of AAAs in the anterioposterior direction.
Spiral CT is a new more rapid method that provides excellent resolution of even visceral aortic branches and facilitates accurate measurement for endovascular graft sizing. Magnetic resonance imaging (MRI) is comparable in accuracy to the CT and avoids radiation . This techique is much more expensive, less readily available and less well tolerable from claustrophobic patients . Arteriography is not an accurate techique to confirm the diagnosis of abdominal aneurysm because trombus within an abdominal aneurysm diminishes the size of the contrast-filled lumen.
It is highly recommended especially for male and smoker patients to include in their routine medical check up after their 50′s an ultrasound exam for the determination of the diameter of their abdominal aorta.
Kindly offered by Kallinis Aristides, Vascular Surgeon.
