Carotid duplex is an ultrasound test that shows how well blood is flowing through the carotid arteries. The carotid arteries are located in the neck. They supply blood directly to the brain.
Scan - carotid duplex; Carotid ultrasound; Carotid artery ultrasound; Ultrasound - carotid; Vascular ultrasound - carotid; Ultrasound - vascular - carotid; Stroke - carotid duplex; TIA - carotid duplex; Transient ischemic attack - carotid duplex
Ultrasound is a painless method that uses sound waves to create images of the inside of the body. The test is done in a vascular lab or radiology department.
The test is done in the following way:
No preparation is necessary.
You may feel some pressure as the transducer is moved around your neck. The pressure should not cause any pain. You may also hear a "whooshing" sound. This is normal.
This test checks blood flow in the carotid arteries. It can detect:
Your health care provider may order this test if:
The results will tell your provider how open or narrowed your carotid arteries are. For example, the arteries may be 10% narrowed, 50% narrowed, or 75% narrowed.
A normal result means there is no problem with the blood flow in the carotid arteries. The artery is free of any significant blockage, narrowing, or other problem.
An abnormal result means the artery may be narrowed, or something is changing the blood flow in the carotid arteries. This is a sign of atherosclerosis or other blood vessel conditions.
In general, the more narrowed the artery is, the higher your risk for stroke.
Depending on the results, your provider may want you to:
There are no risks with having this procedure.
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Bluth EI, Johnson SI, Troxclair L. The extracranial cerebral vessels. In: Rumack CM, Levine D, eds. Diagnostic Ultrasound. 5th ed. Philadelphia, PA: Elsevier; 2018:chap 26.
Polak JF, Pellerito JS. Carotid sonography: protocol and technical considerations. In: Pellerito JS, Polak JF, eds. Introduction to Vascular Ultrasonography. 7th ed. Philadelphia, PA: Elsevier; 2020:chap 5.