Carotid duplex is a special ultrasound scan used to check the carotid arteries for problems with blood flow or changes in the vessel walls.
What is behind the term?
The term carotid duplex, sometimes also called duplex carotid, carotid duplex sonography, or duplex of the carotids, is made up of two parts. "Carotid" refers to the carotid artery, also known medically as the arteria carotis. These arteries run along the left and right sides of the neck and are responsible for supplying the brain with oxygen-rich blood. The word "duplex" refers to the scanning method: duplex sonography. This is a combination of standard ultrasound and a special technique that also makes the speed of blood flow visible.
Unlike a normal ultrasound, which only shows the structure of the vessels, duplex sonography also provides information about how fast and in which direction the blood is flowing through the carotid arteries. This makes the scan particularly useful when it comes to detecting narrowings or deposits.
When is a carotid duplex scan performed?
A carotid duplex scan is usually carried out when there is a suspicion that the carotid arteries are narrowed or have changed in some way. This might be the case after a stroke, with certain risk factors such as high blood pressure or raised cholesterol levels, or when unusual sounds are heard over the carotid artery. The aim is to detect deposits (known as plaques) or narrowings early, as these could increase the risk of a stroke.
Sometimes the scan is also carried out as part of a routine check-up, especially for people who have a higher risk of vascular disease.
How does the scan work?
For a carotid duplex scan, a gel is applied to the skin on the neck. The doctor then moves a small ultrasound probe gently along the carotid arteries. This is usually completely painless and only takes a few minutes. During the scan, you can see on a monitor how the blood is flowing through the vessels. The scan provides both images of the vessel wall and information about the speed and direction of blood flow.
This technique can not only detect narrowings but also assess how severe they are and whether they increase the risk of a stroke.
What do the results mean?
The results of a carotid duplex scan show whether the carotid arteries are clear or whether there are any changes. If deposits or narrowings are found, this may point to arteriosclerosis (hardening of the arteries). Depending on how significant the changes are, the next steps will be discussed with your doctor to decide whether any further action is needed.
The scan itself is not a diagnosis. It is an imaging procedure used to gather more information. Whether treatment is needed depends on the findings and is always decided on an individual basis.
Other terms and spellings
In medical documents, you may come across several variations: carotid duplex, duplex carotid, carotid duplex sonography, or duplex of the carotids. They all refer to the same scan of the carotid arteries using ultrasound and a special Doppler technique.
How this fits into a medical context
Carotid duplex is a scanning procedure, not a diagnosis or a disease. There is no reason to worry simply because this term appears in a medical letter. The scan is used to gather important information about blood supply to the brain and to identify risks at an early stage.
