Renal Artery Stenosis Doppler Scan (RAS)

You may need to have a Renal Artery Stenosis Doppler Scan (RAS) Ultrasound Scan for the following reasons: • To diagnose RAS: RAS is a narrowing of one or both of the renal arteries, which are the blood vessels that supply blood to the kidneys. RAS can be caused by a number of factors, including atherosclerosis (buildup of plaque in the arteries), fibromuscular dysplasia (a condition that affects the muscle walls of the arteries), and blood clots. A RAS Doppler scan can help to diagnose RAS by showing the narrowing of the renal arteries and measuring the blood flow. • To assess the severity of RAS: The RAS Doppler scan can also be used to assess the severity of RAS by measuring the blood flow in the renal arteries. The more severe the narrowing, the slower the blood flow will be. • To monitor the effectiveness of treatment: If you are being treated for RAS, a RAS Doppler scan can be used to monitor the effectiveness of treatment by measuring the blood flow in the renal arteries over time. • To identify other problems with the renal arteries: The RAS Doppler scan can also be used to identify other problems with the renal arteries, such as blood clots, aneurysms (enlargements), and dissections (tears).

• Hypertension (High Blood Pressure): To investigate the potential role of renal artery stenosis as a contributing factor to high blood pressure. • Kidney Function Assessment: To evaluate kidney function and identify issues related to reduced blood flow due to stenosis. • Monitoring of Stent Function: For patients with a history of renal artery stenting, regular Doppler scans help monitor stent function and detect any complications.

During a renal artery stenosis Doppler scan, you will lie on your back on an examination table. A warm gel will be applied to your abdomen, and a transducer (small handheld device) will be used to send ultrasound waves into your body. The transducer will be moved over the area of your abdomen where the renal arteries are located.

There are no known risks associated with renal artery stenosis Doppler scans.

A renal artery stenosis Doppler scan can help to diagnose RAS and to assess its severity. The test can also be used to monitor the effectiveness of treatment for RAS.

The following are some of the abnormalities and findings that may be seen on a renal artery stenosis Doppler scan: • Narrowing of the renal arteries • Decreased blood flow in the renal arteries • Turbulence in the blood flow • Blood clots in the renal arteries Aneurysms (enlargements) of the renal arteries

No, neither procedure is painful and does not require needles or radiation.

Generally, no special preparations are required. Patients can continue their regular routines, including eating, drinking, and taking medications.

You will receive your results verbally after the scan. Besides, the practitioner will examine the relevant images after your appointment and prepare a written report after your scan or within 24 hours with any recommended actions.