Why do I need this test?
The primary purpose of a carotid ultrasound is to screen for a narrowing of the carotid arteries that indicates an increased risk of stroke. Narrowing is usually caused by plaques — a buildup of fats, cholesterol, calcium and other substances that circulate in the bloodstream. Early detection of narrowing of the carotid arteries enables your doctor to begin treatments that improve blood flow to the brain and decrease your risk of stroke.
Your doctor may recommend a carotid ultrasound if you have medical conditions that increase the risk of stroke. These conditions include:
- High blood pressure
- High cholesterol
- Family history of stroke or heart disease
A carotid ultrasound to screen for stroke risk may be used in combination with other tests, including:
- Abdominal ultrasound to screen for potential abdominal aortic aneurysm, an enlargement or ballooning of the large artery that supplies blood to the abdomen, pelvis and legs
- Ankle-brachial index test, a comparison of your blood pressure measured at an ankle and your blood pressure measured at an arm, which can indicate blockage of blood flow to the legs
Other uses of carotid ultrasound
Your doctor also may order a carotid ultrasound to:
- Evaluate the structure and function of the artery after surgery to remove plaques (carotid endarterectomy)
- Evaluate the placement and treatment effect of a stent, a mesh tube used to improve blood flow through an artery and support a weakened artery
- Locate a collection of clotted blood (hematoma) that may inhibit blood flow
- Detect other abnormalities in the structure of a carotid artery that may disrupt blood flow