Banner image

Carotid duplex

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

Find

Learn More

Definition

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.

How the Test is Performed

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:

  • You lie on your back. Your head is supported to keep it from moving. The ultrasound technician applies a water-based gel to your neck to help with the transmission of the sound waves.
  • Next, the technician moves a wand called a transducer back and forth over the area.
  • The device sends sound waves to the arteries in your neck. The sound waves bounce off the blood vessels and form images or pictures of the insides of the arteries.

How the Test will Feel

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.

How to Prepare for the Test

No preparation is necessary.

Normal Results

The results will tell your doctor 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.

Risks

There are no risks with having this procedure.

What Abnormal Results Mean

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 of stroke.

Depending on the results, your doctor may want you to:

Why the Test is Performed

This test checks blood flow in the carotid arteries. It can detect:

  • Blood clotting (thrombosis)
  • Narrowing in the arteries (stenosis)
  • Other causes of blockage in the carotid arteries

Your doctor may order this test if:

  • You have had a stroke or transient ischemic attack (TIA)
  • You need a follow-up test because your carotid artery was found to be narrowed in the past or you have had surgery on the artery
  • Your doctor hears an abnormal sound called a bruit over the carotid neck arteries. This may mean the artery is narrowed.

Review Date: 6/25/2018
Reviewed By: Amit M. Shelat, DO, FACP, Attending Neurologist and Assistant Professor of Clinical Neurology, SUNY Stony Brook, School of Medicine, Stony Brook, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

ADAM QualityA.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 9-1-1 for all medical emergencies. Links to other sites are provided for information only—they do not constitute endorsements of those other sites. © 1997-2010 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.