A carotid ultrasound is a medical imaging test that uses high-frequency sound waves to create pictures of the carotid arteries in the neck. These two large arteries deliver blood directly from the heart to the brain, and the non-invasive procedure helps assess their structure. Physicians use this examination to look for narrowing, blockages, or plaque buildup, which can indicate stroke risk. The scan, often called a carotid duplex, also uses Doppler technology to measure the speed and direction of blood flow through the vessels.
Essential Preparation Steps
Preparation for this scan focuses on ensuring clear access to the neck area and minimizing factors that could interfere with blood flow measurements. Patients should wear comfortable, loose-fitting clothing that allows the neck to be easily exposed, such as a shirt with a low or open collar. Avoid garments like turtlenecks or high-collared blouses, which might obstruct the sonographer’s access during the examination. If clothing is too restrictive, the technician may ask the patient to change into a gown.
All jewelry, including necklaces and earrings, should be removed prior to arriving at the facility, as metal objects can interfere with sound waves and image clarity. Patients should also avoid applying lotions, creams, or powders to the neck and chest on the day of the test. These products can create a barrier between the skin and the ultrasound gel, compromising the quality of the diagnostic images.
While most carotid ultrasounds require no fasting or change in routine medication, confirm specific guidelines with the ordering physician or the testing facility. Some facilities advise avoiding caffeine and nicotine for at least two hours before the appointment. Both substances cause temporary vasoconstriction, which can alter blood flow dynamics and affect the accuracy of the Doppler measurements. Follow the instructions provided by the clinic to ensure the most accurate results.
What Happens During the Ultrasound
Once in the exam room, the patient lies on their back on an examination table, often with the head slightly tilted to better expose the neck. The sonographer, the trained technologist who performs the scan, applies a warm, water-based gel to the skin over the carotid arteries on both sides of the neck. This gel eliminates air pockets and ensures efficient transmission of the high-frequency sound waves from the transducer into the body.
The sonographer moves a handheld device called a transducer across the lubricated area of the neck. Patients may feel slight pressure as the technologist positions the probe to capture clear images of the arteries and surrounding tissues. During the Doppler portion of the test, a distinct whooshing or pulsatile sound may become audible, representing the flow of blood through the vessels. The entire procedure is non-invasive, painless, and usually takes between 30 to 45 minutes.
Receiving Your Results
After the images and blood flow data are captured, the patient can wipe off the remaining gel and leave the facility immediately, with no recovery time needed. The sonographer cannot discuss the findings, as the images must first be analyzed by a physician specializing in interpreting medical images, usually a radiologist. This specialist prepares a detailed report summarizing the structural findings and blood flow measurements. The finalized report is sent to the healthcare provider who ordered the test, who will then contact the patient to discuss the findings and determine next steps.