Carotid Artery Disease

Carotid artery stenosis is often diagnosed after you’ve experienced symptoms of a stroke. The symptoms prompt your healthcare provider to thoroughly check for any type of blockage, which can lead to a discovery of carotid artery stenosis. This condition can also be diagnosed after your provider hears an abnormal sound — called a bruit (whistling sound) or murmur — during an exam of your neck with a stethoscope. There are several tests providers use to confirm a diagnosis of carotid artery stenosis and learn more about the size and location of the blockage. These tests can include:

• Ultrasound: Also called a duplex ultrasound, this type of test uses sound waves to create an image of your body’s internal structures. An ultrasound is a painless test that is done on top of your skin. An ultrasound is used to see how blood is flowing through your arteries and find any places where the arteries may be blocked or narrowed.
• Computed tomography angiography (CTA): Using a CT scanner — a device that uses X-rays to create a detailed image of your internal organs — your provider can take a detailed view of your carotid arteries. During this test, dye is injected into your bloodstream that will help show any blockages on the images. This test may be used on people with pacemakers or stents from other conditions.
• Cerebral angiography: This type of diagnostic test involves using a catheter in a minimally invasive procedure to go into your arteries and get a close look at the blockage. Also in this test, your provider injects contrast material directly into your arteries so that they can see the artery details.
• Magnetic resonance angiography (MRA): Similarly to a CT scan but without using X-rays, this test provides detailed images of your arteries. It’s a noninvasive imaging test.

How is carotid artery stenosis classified?

During the diagnosis process, your healthcare provider will look to see if you have the condition, how large it is, and where it’s located. Carotid artery stenosis is generally divided into three groupings: mild, moderate and severe. A mild blockage is one that’s less than 50%. This means that less than half of your artery is blocked. A moderate blockage is between 50% and 79%. The most severe classification involves having the majority of your artery blocked — from 80% to 99%.