A carotid test, often called a carotid ultrasound, is a common and non-invasive diagnostic tool used to assess the health of the arteries located in your neck. This test provides insights into blood flow and helps identify potential issues, contributing to proactive health management.
What Carotid Arteries Are and How the Test Works
Carotid arteries are major blood vessels situated on each side of your neck. Their primary function involves supplying oxygen-rich blood to your brain, face, and neck. There are two main branches: the internal carotid artery, which delivers blood to the brain, and the external carotid artery, which supplies the face, neck, and scalp.
The carotid test, also known as a carotid ultrasound or carotid duplex scan, uses high-frequency sound waves to create images of these arteries. A small, handheld device called a transducer emits sound waves that bounce off tissues and blood cells. A computer then translates these echoes into real-time images displayed on a monitor, allowing healthcare professionals to visualize the artery structure and measure blood flow. This procedure is non-invasive and generally painless.
Reasons for a Carotid Test
A medical professional may recommend a carotid test for several reasons, particularly to assess the risk of stroke. The test is performed to detect carotid artery disease, which involves the narrowing or blockage of these arteries due to plaque buildup. This plaque, composed of fatty deposits, cholesterol, and other substances, can restrict blood flow to the brain.
Certain risk factors increase the likelihood of developing carotid artery disease. These include high blood pressure, high cholesterol, diabetes, smoking, and a family history of stroke or heart disease. Age is also a contributing factor, with the risk increasing as individuals get older. A carotid test may also be suggested if a medical professional hears an abnormal sound, known as a bruit, in the carotid arteries during a physical examination.
Symptoms that might prompt a carotid test often relate to a transient ischemic attack (TIA), sometimes called a “mini-stroke.” These temporary symptoms can include sudden weakness or numbness on one side of the body, vision changes, slurred speech, confusion, or dizziness. Detecting carotid artery disease early through this test can help in developing strategies to lower the risk of a stroke.
How the Carotid Test is Performed
The carotid test is a straightforward procedure that typically requires minimal preparation. You will generally be asked to wear comfortable clothing with an open neck and to remove any neck jewelry that might interfere with the scan. Some instructions might suggest avoiding smoking or caffeine for a few hours before the test, as these can temporarily affect blood vessel size.
During the test, you will lie on your back, and a sonographer or technician will apply a warm, water-based gel to the sides of your neck. This gel helps the transducer make good contact with the skin and transmit sound waves effectively. The technician will then gently press the handheld transducer against your neck, moving it to capture images of the carotid arteries. You may hear “whooshing” sounds as the device measures blood flow. The procedure usually takes about 15 to 30 minutes to complete.
Understanding Your Carotid Test Results
After your carotid test, a medical professional, often a radiologist, will review the images and interpret the findings. If your results are normal, it means there is no significant narrowing, blockage, or plaque buildup in your carotid arteries, and blood flow is smooth. A normal peak systolic velocity (PSV), typically less than 125 cm/s, is an indicator of healthy blood flow.
Abnormal results typically indicate the presence of atherosclerosis, which is plaque buildup, or narrowing of the arteries, a condition known as stenosis. The degree of stenosis is often categorized as mild (less than 50% blockage), moderate (50% to 69% blockage), or severe (70% or more blockage). For example, a severe stenosis might show a peak systolic velocity (PSV) greater than 230 cm/s. The severity of the narrowing helps medical professionals assess your risk of stroke.
Your doctor will discuss the test results with you and recommend a course of action based on the findings. For mild narrowing, lifestyle adjustments such as dietary changes, regular exercise, and smoking cessation may be suggested. Medications to manage blood pressure or cholesterol might also be prescribed. In cases of moderate to severe stenosis, particularly if you have experienced symptoms, further evaluation or procedures could be considered to reduce stroke risk.