Name of the Procedure:

Duplex Scan of Extracranial Arteries; Complete Bilateral Study
Common name(s): Carotid Duplex, Carotid Ultrasound, Carotid Doppler

Summary

A Duplex scan of the extracranial arteries is a non-invasive imaging test that uses high-frequency sound waves to evaluate the blood flow and structure of the carotid arteries in the neck. This procedure is performed on both sides (bilateral) to detect any blockages or abnormalities that could affect blood flow to the brain.

Purpose

The primary goal is to diagnose conditions that could lead to a stroke or other complications by detecting blockages, narrowing (stenosis), or other abnormalities in the carotid arteries.

Indications

• Symptoms of stroke or transient ischemic attack (TIA), such as sudden weakness or numbness on one side of the body, difficulty speaking, or loss of vision.
• Known risk factors for cerebrovascular disease, including high blood pressure, diabetes, high cholesterol, or a history of smoking.
• Abnormal physical examination findings, such as a bruit (unusual sound) heard over the carotid artery.

Preparation

• No special preparation is typically required.
• Patients may be advised to avoid caffeine or nicotine before the test to prevent temporary changes in blood flow.
• Wear comfortable clothing with an easily accessible neckline.

Procedure Description

1. The patient lies on an examination table with their neck exposed.
2. A clear gel is applied to the skin over the carotid arteries.
3. A handheld device called a transducer is moved over the gel-coated skin, emitting sound waves that create images and measure blood flow on a monitor.
4. The procedure is repeated on the opposite side of the neck for a complete bilateral study.

The scan does not require anesthesia or sedation.

Duration

Typically, the procedure takes about 30-45 minutes.

Setting

The procedure is usually performed in a hospital radiology department, outpatient clinic, or specialized vascular lab.

Personnel

• A registered vascular technologist (RVT) or an ultrasound technician performs the scan.
• A radiologist or vascular specialist interprets the results.

Risks and Complications

The procedure is safe with minimal risks:

• Minor discomfort from the pressure of the transducer.
• Skin irritation from the gel, though this is rare.

Benefits

• Provides detailed information about the blood flow and structure of the carotid arteries.
• Helps identify risk of stroke or other vascular issues, allowing for timely intervention.
• Non-invasive and painless.

Recovery

• No recovery time is needed; patients can resume normal activities immediately after the procedure.
• Follow-up appointments may be scheduled to discuss the results and any necessary treatments or interventions.

Alternatives

• Magnetic Resonance Angiography (MRA): Offers detailed images but involves magnetic fields and sometimes contrast dye.
• CT Angiography (CTA): Provides detailed images using X-rays and contrast dye, which involves radiation exposure.

Both alternatives are more invasive and may require contrast material, which can pose risks for individuals with kidney issues or allergies.

Patient Experience

• The patient will feel the coolness of the gel and slight pressure from the transducer.
• The procedure is generally comfortable, and patients remain awake and conscious.
• Any discomfort is usually minimal and short-lived.