A carotid ultrasound is an exam that combines two types of ultrasound to look for blockages in your carotid arteries. It is simple and painless.

The carotid arteries are located along both sides of your neck. Blocked carotid arteries are a major risk factor of stroke.

An ultrasound is a type of scan that uses sound waves to produce a picture of the inside of your body. The two types of ultrasound used in a carotid ultrasound are conventional ultrasound and Doppler ultrasound.

Conventional, or B-mode, ultrasound uses sound waves that bounce off blood vessels to provide a picture of the structure of your blood vessels.

Doppler ultrasound uses sound waves that track moving objects. This allows your doctor to see how your blood is moving through your blood vessels.

Other names for a carotid ultrasound are:

  • carotid artery Doppler sonography
  • carotid artery duplex scan
  • carotid artery ultrasound
  • carotid duplex scan
  • vascular ultrasound

As we age, our arteries tend to develop a sticky substance called plaque. Plaque buildup is related to:

If plaque builds up in your carotid arteries, it’s called carotid artery disease.

According to the Society of Cardiovascular Angiography and Interventions, around 1 percent of 50- to 59-year-olds and 10 percent of 80- to 89-year-olds have narrowed or blocked carotid arteries.

A 2018 study looked at the rates of carotid plaque in healthy 40- to 49-year-old men living in three different countries. The researchers discovered carotid plaque in:

  • 22.8 percent of white men in Pittsburgh, Pennsylvania, United States
  • 10.6 percent of Korean men in Ansan, South Korea
  • 4.8 percent of Japanese men in Ōtsu, Japan

A 2012 study looked at the rate of carotid artery disease in people who were at least 60 years old and had certain coexisting conditions, such as diabetes or coronary artery disease, in Brazil.

The researchers found that 7.4 percent of the study participants had carotid artery disease.

If your doctor thinks you may have carotid artery disease, they’ll order a carotid ultrasound.

Carotid artery disease is a major risk factor of stroke. Cholesterol buildup in the carotid arteries can create blood clots. If these clots break off, they can travel to your brain and cause a stroke.

The first symptom of carotid artery disease is often a stroke or ministroke (transient ischemic attack). Some early warning signs of a stroke are:

  • weakness, numbness, or tingling on one side of your body or in your arm or leg
  • an inability to move your arm or leg
  • an inability to speak clearly, or having garbled speech
  • an inability to see in one eye, or peripheral vision loss

Get immediate medical help if you experience any of these warning signs, even if they go away. It could mean that you’ve had a stroke or that you’re about to have one.

When you get medical help, a doctor will ask you questions about your symptoms and your medical history. They will measure your blood pressure and may also listen to the blood flow in your neck.

This test doesn’t require much preparation. However, you may be asked not to smoke or drink caffeine for at least 2 hours before the test. Smoking and caffeine use can shrink your blood vessels and affect the accuracy of the test.

Other steps you can take before your test include:

  • wearing comfortable clothing with an open neck
  • avoiding turtlenecks or silk clothing, which could be stained by the ultrasound gel
  • removing any jewelry

A carotid ultrasound takes place in an ultrasound lab. It lasts about 15 to 30 minutes. The following steps occur during this procedure:

  1. You’ll lie down on the examination table with your head bent slightly backward.
  2. An ultrasound technician will apply a gel to your neck.
  3. The technician will move a small ultrasound wand along the area where your carotid arteries are located. You may feel slight pressure and hear a whooshing noise. That’s the sound of your blood moving through your vessels.
  4. The ultrasound images are sent to a computer and recorded for your doctor.

Ultrasound is a risk-free way for your doctor to view any changes and abnormalities in your body.

Doctors diagnose most cases of carotid artery disease with the help of a carotid ultrasound. Your doctor can order more tests if they need more information.

If your doctor diagnoses carotid artery disease, they’ll recommend treatment based on how severe it is. You may need surgery to remove the plaque in your arteries, or you might need what’s called carotid angioplasty and stenting.

During carotid angioplasty and stenting, your doctor threads a catheter up through your carotid artery to the location of the blockage. The catheter inflates a small balloon to flatten the plaque. Then, a stent is inserted to keep your arteries open. A stent is a small, metal mesh tube.

Your doctor may also prescribe medications to thin your blood or control the levels of lipids in your blood.

Lifestyle changes are also important for treating and preventing carotid artery disease. They include things like quitting smoking, adopting a balanced diet, and exercising.