An overview of Carotid Ultrasound
A carotid ultrasound is a noninvasive, painless medical test that uses sound waves to examine the blood flow through the carotid arteries, which are located on each side of the neck and deliver blood from the heart to the brain. This test is used to look for narrowed carotid arteries, which can increase the risk of stroke. Early diagnosis and treatment of a narrowed carotid artery can decrease stroke risk. The results of the test can help health care providers determine the best treatment approach to lower stroke risk.
What is Carotid Ultrasound used for?
A carotid ultrasound is used to assess the blood flow through the carotid arteries, evaluate the thickness of the carotid artery wall, and check for clots. It helps determine the presence of narrowed or blocked carotid arteries, which can increase the risk of stroke. The test is done to diagnose and treat conditions that may lead to stroke, such as high blood pressure, diabetes, high cholesterol, family history of stroke or heart disease, recent transient ischemic attack (TIA) or stroke, unusual sounds in the carotid arteries (bruit) detected using a stethoscope, coronary artery disease, or hardening of the arteries. Additionally, it may be used to evaluate blood flow after surgery to remove plaques, the placement and effectiveness of a stent, or to locate a collection of clotted blood (hematoma) that may prevent blood flow. If the results of the carotid ultrasound are unclear, further imaging tests, such as a computerized tomography angiogram (CTA) scan, magnetic resonance imaging (MRI), contrast-enhanced ultrasound (CEUS), or 3D ultrasound, may be performed.
How to prepare for Carotid Ultrasound?
Patients are advised to wear a comfortable shirt with no collar or an open collar for the carotid ultrasound test. It is also recommended not to wear a necklace or dangling earrings during the procedure. Unless the health care provider or the radiology lab provides special instructions, there are generally no other specific preparations needed for the test. It is always best to confirm the appointment time and location with the healthcare provider the day before the exam.
How is Carotid Ultrasound conducted?
A carotid ultrasound is conducted by a technician using a small, hand-held device called a transducer. The transducer emits sound waves and records the echo as the waves bounce off tissues, organs, and blood cells. A computer translates the echoed sound waves into a live-action image on a monitor. The ultrasound technician may use a Doppler ultrasound, which shows blood flowing through the arteries. The procedure typically takes about 30 minutes and involves the technician applying a warm gel to the skin above the site of each carotid artery, gently pressing the transducer against the side of the neck, and capturing images.
How are Carotid Ultrasound results reported?
The results of a carotid ultrasound are usually reported by a radiologist who specializes in interpreting imaging tests. The radiologist prepares a report for the health care provider who ordered the test, which may be a health care provider, a cardiologist, or a neurologist. In some cases, the radiologist may discuss the results of the test with you immediately after the procedure. The health care provider who ordered the test will explain the results to you and advise on the next steps based on the findings. If the test reveals a risk of stroke, the health care provider may recommend lifestyle changes, medications, or further testing or treatment.
Understanding the report
A doctor who specializes in imaging tests, called a radiologist, will review your carotid ultrasound results and prepare a report for the healthcare provider who ordered the test. This report will help the healthcare provider determine if there are any narrowed or blocked carotid arteries, which can increase the risk of stroke. The healthcare provider will then discuss the results with you and explain what the ultrasound reveals about your condition and what that means for your health. If necessary, they may recommend further tests or treatments based on the severity of the blockage in your arteries.
Limitations and Considerations
The limitations of the carotid ultrasound test include:
- Underestimating narrowing: 3D ultrasound may underestimate narrowing of the carotid artery.
- Limited visualization of soft plaque: Carotid ultrasound may not provide detailed information about the composition of plaque in the arteries, specifically the soft plaque that is more prone to rupture and cause blockages.
- Limited evaluation of smaller vessels: The test's accuracy may be limited when evaluating smaller branches of the carotid arteries.
It's important to note that carotid ultrasound is a safe and noninvasive procedure that plays a significant role in the early detection and management of stroke risk factors. However, it may not provide a complete picture of the cardiovascular system and may require additional tests for a more comprehensive evaluation. Your healthcare provider will determine whether a carotid ultrasound is appropriate for your specific situation and whether additional tests are necessary.