An arterial duplex exam is a type of ultrasound imaging used to see how blood moves through your veins and arteries. Like other types of ultrasound imaging, an arterial duplex ultrasound uses sound waves that bounce off the body’s internal structures or moving parts, such as blood, to create pictures.

There are several types of duplex ultrasounds. An arterial and venous duplex ultrasound can look at blood flow and blood vessels in the abdomen, but there are also arterial duplex ultrasounds of the extremities, including the legs and arms. Duplex ultrasounds are also available to specifically examine your kidneys and carotid arteries.

In many cases, arterial duplex ultrasounds are prescribed if your doctor thinks an artery may be narrowed or blocked. For example, the exam is commonly used to detect peripheral artery disease (PAD), a condition in which the blood vessels in the legs or lower extremities become narrowed or blocked, thereby affecting blood flow from the heart. 

What Does an Arterial Duplex Exam Entail?

Typically, there’s no advance preparation involved. You may be asked to change into a medical gown so that the ultrasound technician can access your arms and legs easily. You’ll then be directed to lie on an exam table, and the sonographer will apply ultrasound gel to the area being examined. This cool, smooth substance helps sound waves pass through tissue, and will wipe off easily once the exam is finished.

During the exam, the sonographer will move a wand known as a transducer over the area being examined. This device sends the sound waves, which then reflect back from your body and are sent to a computer. The computer processes the sound waves, transforming them into images. You may be asked to lie still, change positions, or hold your breath throughout certain portions of the exam so the technician can capture images from different angles. You shouldn’t feel any discomfort, but there may be minor pressure from the transducer.

Oftentimes, arterial duplex exams of the legs are coupled with an ankle-brachial index (ABI). During this procedure, blood pressure cuffs will be placed on your arms and legs to measure the ABI. This is a ratio of the measurement of your systolic blood pressure at the ankle, compared to blood pressure at the brachial artery, which is located in the upper arm. It is calculated by dividing the blood pressure in the ankle by that in the arm. A value of 0.9 or greater is considered normal, but lower readings could indicate PAD or another issue that may require treatment.

While the test was originally developed to detect PAD, it has since been found that ABI can also be used to indicate atherosclerosis or other cardiovascular concerns. 

If an arterial duplex exam or another type of venous imaging has been recommended for you, turn to Vascular Surgical Associates. In addition to our board-certified vascular surgeons, our team is comprised of experienced ultrasound technicians working in a state-of-the-art vascular lab. Browse through our locations online or schedule an appointment by calling (770) 423-0595.