Kidney artery Doppler ultrasound
renal artery Doppler · renal artery ultrasound · kidney Doppler · renal duplex scan
The doctor uses ultrasound to see how blood flows through the vessels of your kidneys. It shows if they are narrowed.
For high blood pressure that is hard to bring down with medicines, abnormal kidney tests, or after a kidney transplant.
⏱ Duration: usually 20 to 40 minutes; the report is ready right away
Be sure to tell your doctor
How to prepare
- Food. Usually fasting: 6 to 8 hours without food, in the morning. Check with the clinic.
- Gas. For 2 to 3 days before, eat less food that causes gas: cabbage, beans, fizzy drinks, dark rye bread.
- Medicines. Do not stop your usual medicines on your own. If you are unsure, tell your doctor. They will decide.
What to bring
- Your referral
- Blood and urine test results
- Past kidney ultrasounds
- A list of your medicines
How it goes
- You lie on your back, then on your side
- Gel is put on your belly and sides
- The doctor finds the kidney vessels with the probe
- Sometimes you are asked to hold your breath for a few seconds
- The doctor measures how fast blood flows in the vessels
What you'll feel
- Cool gel and pressure from the probe on your belly, sometimes quite firm
- Holding your breath can be tiring. Tell the doctor
Afterwards
- You can eat right away and go back to your day
- The report is usually ready right away
- If narrowing is found, the doctor will decide if another test is needed
Common questions
Why do I need to fast?
Gas in the bowel blocks the ultrasound. The vessels are easier to see on an empty stomach.
Does it take long?
Usually 20 to 40 minutes. The kidney vessels are deep, so the doctor works carefully.