If you have symptoms of peripheral arterial disease (PAD), you may be a candidate for a peripheral vascular ultrasound examination. There are several types of peripheral ultrasound exams, but each uses high-frequency sound waves as the means of detection.
Lower-Extremity Arterial Evaluation
The purpose of a lower extremity arterial evaluation is to detect the presence, severity and location of atherosclerosis (narrowing of the arteries caused by plaque) in your legs. Some of the indications for a lower extremity arterial evaluation include leg pain while walking (claudication), leg pain at rest, leg numbness and tingling, or non-healing ulcers or sores of the legs or feet. A lower-extremity arterial evaluation includes the following components:
Exercise Treadmill Test
If a treadmill test is required, you will walk on a treadmill at a slow speed for five minutes or less. You will be asked to report any symptoms such as leg pain or numbness, hip pain, chest pain or dizziness as soon as they begin. When you have completed the exercise, blood pressures in both legs are obtained.
If the post-exercise blood pressures in your legs are normal, no further testing is required. If the post-exercise blood pressures in your legs differ significantly from those at rest, an ultrasound scan of your legs will be performed.
An ultrasound scan is a painless procedure that uses high-frequency sound waves, which are bounced off structures and moving blood inside the body. The images and signals produced are used to evaluate arterial blood flow.
A water-based gel will be applied to your legs, and an ultrasound probe, or transducer, will be used to scan the arteries in your legs. Images of your arteries and the sound of your blood flow will be recorded. This portion of the examination takes approximately one hour.
If all three portions of the arterial evaluation are performed, the evaluation could take up to 2.5 hours. There is no special preparation for a lower extremity arterial evaluation.
Lower-Extremity Venous Duplex Scan
The purpose of a venous duplex scan is to detect the presence of thrombus (blood clot) in your veins. Some indications for a lower-extremity venous scan include warmth, pain and swelling of one or both legs, or ulcers of legs.
A water-based gel will be applied to your legs, and images of your veins and the sound of blood flow within them will be recorded using ultrasound. You will be asked to perform various breathing maneuvers and will feel compressions of your leg in several places throughout the test. This examination is usually painless, although you may feel some discomfort if your leg is tender. This procedure takes approximately 1 hour to perform, and no special preparation is required.
Abdominal Aorta Duplex Scan
An ultrasound scan of your abdominal aorta is performed to detect aneurysms (weakening and stretching of the walls of the aorta). A water-based gel will be applied to your abdomen, and images of your abdominal aorta and the sound of blood flow will be recorded using and ultrasound transducer. This procedure is painless and will take approximately 45 minutes. It is necessary to refrain from eating and drinking for six hours prior to this procedure.
Carotid-Artery Duplex Scan
The purpose of a carotid-artery duplex scan is to detect the presence of atherosclerosis (narrowing caused by plaque) in your carotid arteries, which are the arteries in your neck that supply blood flow to your brain. Some indications for a carotid artery duplex scan include weakness, paralysis or dysfunction of limbs, change in speech, visual disturbances, numbness or tingling in limbs, and balance disturbances. Your doctor may also order a carotid duplex scan if he detects a bruit (sound or murmur) when he listens to the blood flow in your neck with his stethoscope.
A water-based gel will be applied to your neck, and an ultrasound transducer will be used to obtain the images and sound of your blood flow. This scan is painless and takes approximately 45 minutes to an hour. No special preparation is required for this examination.