Duplex Scan of the Carotid and Vertebral Arteries
Significant narrowing of the carotid and vertebral arteries, the major vessels in the neck which carry blood flow to the brain, will impair the brain’s functions by decreasing the blood flow to that organ. Duplex scanning and Doppler color flow imaging are highly accurate ultrasound techniques used to detect the presence of cholesterol deposits, known as “plaque”, on the walls of the arteries or narrowing of the vessels which obstruct blood flow.
Indications for Testing
- Asymptomatic carotid bruit
- Weakness or numbness on either side of your body
- Inability to move an arm, leg, hand or foot
- Changes in vision or speech
- Lightheadedness, dizziness or blackouts
- History of stroke
- Headaches or memory impairment
- Follow-up after carotid artery surgery, or for known asymptomatic disease
Duplex scanning and Doppler color flow imaging use high frequency sound waves to examine the carotid and vertebral arteries from the base of the neck to the level of your jaw. The instrument sends sound waves into your body and receives back echoes of this sound. The echoes can be used to create a picture of these vessels and contain information about the speed of blood flow through the arteries. This information is used to determine the presence and severity of disease in these important blood vessels.
The actual test procedure is quite simple. You will be asked several questions about your past medical history and your present symptoms for your permanent, confidential laboratory record. Next you will be asked to lie down on an examination table or to have a seat on the chair. The technologist will place a small amount of acoustic gel on your neck in the region to be scanned. A small hand-held ultrasound transducer will be moved over the side of your neck while sound waves are sent into your arteries…a safe, painless procedure. An image of your arteries, produced by bounding the sound waves off the blood vessel, will be seen on the TV monitor of the ultrasound system. Using the image as a guide, the technologist can record the blood flow patterns from discrete areas of the artery for interpretation.
The information gained from this test is used to determine the amount of disease in your arteries and will help to decide the proper treatment, if necessary, for you. Your doctor may recommend further testing, medical management, or surgical intervention for your disease. If the scan is normal, disease within the carotid arteries in your neck can be eliminated as the cause of your symptoms. If necessary, you will be rescheduled for a follow-up duplex scan in three to six months.