What is a Carotid Doppler Ultrasound (US) Scan?
Ultrasound machine uses high frequency sound waves to produce images of the internal structure of the human body. The Doppler ultrasound uses a physics principle to tell the direction of blood flow in the organ scanned. In a Carotid Doppler Ultrasound scan, the neck vessels supplying blood to the brain is examined for patency, the presence of obstruction and the direction of flow.

How safe is the Carotid Doppler Ultrasound Scan?
There is no x-ray used.

Why should I have a Carotid Doppler Ultrasound Scan?
As part of an assessment for the risk of a stroke. If carotid ultrasound examination shows narrowing of the carotid artery, measures can be taken to restore the free flow of blood to the brain. As a result, many strokes are prevented.

Who should have a Carotid Doppler Ultrasound Scan?
Anyone who is at risk for a stroke with symptoms that possibly attributed to carotid narrowing, or findings such as a carotid bruit.
Asymptomatic individuals with the following risk factors:
1. diabetes mellitus
2. high cholesterol levels
3. hypertension
4. family history of stroke or heart disease.

How can I prepare for the Carotid Doppler Ultrasound Scan?
There is no special preparation needed for the scan. You will have to remove any jewelry or accessories around your neck.

How is the Carotid Doppler Ultrasound (US) Scan done?
You will be taken to the ultrasound suite which is dimly lit. You will have to lie flat on a bed and a transparent gel is applied on the neck. Both sides of the neck are examined in turn. A transducer connected to the scanning machine is put on the neck and moved around to follow the blood vessels along the entire length of your neck to obtain the arteries from different perspectives. The transducer sends sound waves into your body. The sound waves bounce off a vessel like an echo. The ‘echo’ is sent to a machine that records the results on film and on a computer. You will not hear or feel the high frequency sound waves. You will be asked to remain as still as you can.

How long does a US Scan take?
It would take up to 30-40 minutes depending on the complexity of the scan.

What happens after the US Scan?
There is actually nothing much to anticipate after the scan.

Are there any possible complications?
There are no known complications or side effects.

What does it mean if my US Scan is abnormal?
If the carotid ultrasound shows a narrowing of one or both carotid arteries, your doctor may suggest medication, non-invasive angiography, or an operation to restore the normal blood flow to the brain. By doing this, you may prevent a stroke from occuring.

What does a normal US Scan mean?
It means that the blood vessels supplying the brain visualized at the neck are not obstructed or narrowed. The risk of you having a stroke due to an inadequate supply of blood to the brain from narrowed or diseased vessels is low.