What Is Carotid Doppler?
Carotid (ka-ROT-id) Doppler is a painless and harmless test that uses high-frequency sound waves to create pictures of the insides of the two large arteries in your neck.
These arteries, called carotid arteries, supply your brain with oxygen-rich blood. You have one carotid artery on each side of your neck.
Carotid Doppler shows whether a substance called plaque (plak) has narrowed your carotid arteries. Plaque is made up of fat, cholesterol, calcium, and other substances found in the blood. Plaque builds up on the insides of your arteries as you age. This condition is called carotid artery disease.
Too much plaque in a carotid artery can cause a stroke. The plaque can slow down or block the flow of blood through the artery, allowing a blood clot to form. A piece of the blood clot can break off and get stuck in the artery, blocking blood flow to the brain. This is what causes a stroke.
A standard carotid ultrasound shows the structure of your carotid arteries. Your carotid ultrasound test may include a Doppler ultrasound. Doppler ultrasound is a special test that shows the movement of blood through your blood vessels.
Your doctor often will need results from both types of ultrasound to fully assess whether there’s a problem with blood flow through your carotid arteries.
Who Requires a Carotid Doppler?
A carotid Doppler checks for plaque buildup in the carotid arteries. Plaque can narrow or block your carotid arteries, preventing oxygen-rich blood from reaching your brain.
Your doctor may recommend a carotid Doppler if you:
Your doctor also may recommend a carotid Doppler if he or she suspects you may have:
A carotid Doppler also may be done to see whether carotid artery surgery, also called carotid endarterectomy (END-ar-ter-EK-to-me), has restored normal blood flow through your carotid artery.
If you had a procedure called carotid stenting, you may have carotid Doppler afterward to check the position of the stent put in your carotid artery. (The stent, a small mesh tube, helps prevent the artery from becoming narrowed or blocked again.)
Sometimes a carotid Doppler is used as a preventive screening test in people who have medical conditions that increase their risk of stroke, including high blood pressure and diabetes.
People who have these conditions may benefit from having their carotid arteries checked regularly, even if they show no signs of plaque buildup.
What To Expect Before Carotid Doppler?
Carotid Doppler is a painless test, and typically there is little to do in advance.
What To Expect During Carotid Doppler?
Carotid Doppler usually is done in a doctor’s office or hospital. The test is painless and often doesn’t take more than 30 minutes.
The Doppler machine includes a computer, a video screen, and a transducer. A transducer is a hand-held device that sends and receives Doppler waves into and from the body.
You will lie on your back on an exam table for the test. Your technician or doctor will put a gel on your neck where your carotid arteries are located. This gel helps the Doppler waves reach the arteries better.
Your technician or doctor will put the transducer against different spots on your neck and move it back and forth. The transducer gives off Doppler waves and detects their echoes after they bounce off the artery walls and blood cells. Doppler waves can’t be heard by the human ear.
A computer uses the echoes to create and record pictures of the insides of the arteries (usually in black and white) and your blood flowing through them (usually in colour; this is a colour Doppler). A video screen displays these live images for your doctor to review.
What To Expect After Carotid Doppler?
You usually don’t have to take any special steps after a carotid Doppler. You should be able to return to normal activities right away.