A Answers (7)
A good history and physical exam is the beginning and critical step in establishing a diagnosis. If a physician suspects that a patient has a carotid narrowing, he or she will refer the patient for an imaging test. Diagnosis is usually made by Duplex Ultrasound and may be confirmed with other imaging tests such as CT or MRI.
Stroke neurologist Dr. Carolyn Brockington explains how carotid artery disease is diagnosed. Watch Dr. Brockington's video for important tips and information about the health of your brain.
Atherosclerosis in the carotid artery creates turbulent blood flow. This turbulence results in a rushing sound that can be heard with a stethoscope. This abnormal sound is called a bruit (pronounced BROO-ee). The presence of a bruit, however, does not always signify a significant blockage. The primary diagnostic tool for carotid artery disease is a carotid duplex ultrasound. This test is painless, and risk free, and uses high frequency sound waves to detect a significant narrowing. If a tight narrowing is found in the artery, further tests may be needed to determine the best treatment. Carotid angiography is an invasive procedure involving the insertion of a catheter (thin flexible tube) into a blood vessel in the arm or leg. The catheter is then guided to the carotid arteries with the aid of a special x-ray machine and contrast dye is injected through the catheter to visualize the arteries. Magnetic resonance angiography, a newer technique, does not involve the use of radiation or the insertion of a catheter. A special contrast agent is injected through a peripheral IV in the arm and images of the carotid arteries are obtained. The resolution of these images, however, may not be as good as those obtained with the more invasive carotid angiography.
When your doctor suspects that you have a significant degree of stenosis in your carotid arteries, she or he will examine you and conduct tests including:
- Duplex ultrasound cerebral angiogram
- Magnetic resonance angiogram (MRA)
- Computed tomography angiogram (CTA)
Although symptoms or physical exam may detect carotid stenosis, the best way is found with imaging. Primarily we use carotid ultrasound, but x-ray studies or MRI are frequently used not only to diagnose the condition but to allow better treatment of it using catheter-based intervention.
Physicians have a number of techniques available to them for diagnosing carotid artery disease. Your doctor will first take your medical history, nothing risk factors such as high blood pressure, diabetes, or a family history of carotid artery disease. At this time, your physician will also make note of any previous signs of carotid artery disease, such as strokes or transient ischemic attacks (“mini-strokes”).
Your physician will then give you a physical exam. As part of this exam, your doctor may hold a stethoscope over the carotid arteries on either side of your neck and ask you to hold your breath. If your doctor hears a whooshing sound, called a bruit, you may have narrowing of the carotid arteries. This test predicts narrowing of the arteries better than it does impending stroke, and is used as a starting point for diagnosis, rather than confirmation of a diagnosis.
Discovery of a bruit or other indicators may then prompt your physician to refer you for diagnostic tests such as carotid ultrasound, computed tomography (CT) angiography, magnetic resonance angiography (MRA), or cerebral angiography.
For diagnosing carotid artery disease, a standard test is to ultrasound the carotid artery. If the ultrasound shows areas of concern, a CT angiography is the next step.
This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.