Abdominal Aortic Aneurysm: AAA

An Abdominal Aortic Aneurysm is an enlarged area in the lower part of the major vessel that supplies blood to the body (aorta).

The aorta is the largest blood vessel in the human body. It carries blood from your heart up to your head and arms and down to your abdomen, legs, and pelvis. The walls of the aorta can swell or bulge out like a small balloon if they become weak. The larger the aneurysm, the more likely it is to break open or tear. This can be life-threatening.  

Which Ultrasound Scanner is used for the AAA?

To confirm the presence of the AAA, a physician can order imaging tests including Abdominal Ultrasound which is a highly accurate way to measure the size of the aneurysm. The physician may also use the color Doppler Ultrasound Scanner L2CD to examine blood flow through the aorta.

Yet, the Linear Ultrasound Scanner L2CD is a special ultrasound technique that allows the physician to see and evaluate blood flow through arteries and veins in the abdomen, arms, legs, neck, and/or brain (in infants and children) or within various body organs such as the liver or kidneys.

The L2CD can quickly and accurately identify the AAA when performed by appropriately trained emergency medicine providers.

The cause of the AAA is currently unknown. However, certain factors have been shown to increase the risk for Abdominal Aortic Aneurysm such as:

*Smoking which can directly damage the walls of the arteries.

*Hypertension or high blood pressure can weaken the walls of the aorta.

*Vasculitis which is also known as vascular inflammation that is a serious inflammation within the aorta and other arteries can occasionally cause AAA.

Aneurysms can form in any blood vessel in the body. However, AAA is considered particularly serious because of the size of the aorta.

AAA are commonly divided according to their size and symptomatology. An aneurysm is usually defined as an outer aortic diameter over 3 cm (normal diameter of the aorta is around 2 cm), or more than 50% of normal diameter.

If the outer diameter exceeds 5.5 cm, the aneurysm is considered to be large.

Yet, ruptured AAA should be suspected in any older (age >60) person with collapse, unexplained low blood pressure, or sudden-onset back or abdominal pain.

Abdominal pain, shock, and a pulsatile mass are only present in a minority of cases. Although an unstable person with a known aneurysm may undergo surgery without further imaging, the diagnosis will usually be confirmed using ultrasound scanning.

To sum up, there may be variations in the measurement of the aneurysm size depending on technique. The aneurysmal sac should be measured from the outer wall to the outer wall with a longitudinal image. The transverse diameter should be measured perpendicular to the long axis of the aorta.

References: Abdominal Aortic Aneurysm , AAA’s Factors , Abdominal Aortic Aneurysms   , Screening for abdominal aortic aneurysms