Because the aorta and iliac arteries lie underneath your intestines it is important that you please fast for this ultrasound scan – no food or drink (except if you require it for taking medication) in the four hours before your scan. Small amounts of water is ok
The abdominal aorta is the large artery which takes the blood from your heart down through your abdomen and onwards to the legs.
There are several important branches that come from the abdominal aorta that we check these branches as well as the aorta with ultrasound. These branches take blood to your abdominal and pelvic organs as well as eventually your legs. Around the level of the belly button the aorta branches into two, these arteries are called the iliac arteries one goes to the right side and one to the left side.
There are two main reasons we want to look at the abdominal aorta; firstly, we want to check that the artery has not become enlarged. When the artery becomes significantly dilated, this is called an aneurysm. The aorta is typically considered to be aneurysmal when it measures more than 3cm in diameter. Your doctor might want this to be monitored periodically by ultrasound or CT imaging routinely. It is possible to get aneurysms in other areas too; for example, the iliac arteries (also in your abdomen) and the artery behind the knee (called the popliteal artery). These may need monitoring as well.
The second reason is to check the aorta and the iliac arteries for any significant narrowing. The narrowing that can occur is usually described as atherosclerosis. The atherosclerosis causes plaque which is made up of fatty material which can become calcified and hard. As it develops it obstructs the blood flow through the artery and this can impact how well the organs or muscles function. If you have a severe atherosclerosis in the aorta or iliac arteries then this can result in symptoms of tiredness or pain in the muscles of your thighs and buttocks when you walk. This is known as intermittent claudication, the symptoms are pain or discomfort when walking a short distance which then improves when you rest, but recurs when you start walking again.
The vascular sonographer will use the ultrasound machine to look inside the arteries to assess how narrow the peripheral arteries have become. They can determine how severe the atherosclerosis is by using its visual appearance and the speed that flow has to travel to get through the narrowed areas. The artery may even become completely blocked. You may have previously have had stents inserted or bypass grafts, the sonographer can see these and can see if there is any new narrowing or blockage.
Once they have seen finished your scan, the sonographer will create a provisional report for the referring doctor. This vascular ultrasound scan and your clinical history will help to determine an appropriate treatment plan to monitor your health and improve your symptoms.