A Doppler ultrasound is an imaging test used to evaluate the way blood moves through the blood vessels. It is the only imaging test able to show blood flow and helps doctors diagnose vascular disease or determine the success of treatments for arteries and veins.
There are different types of Doppler ultrasound, but all use the Doppler effect (an increase or decrease in wavelength) to measure sound waves that reflect off of moving blood cells to create an image.
Why Do You Need a Doppler Ultrasound?
Doppler ultrasounds help your provider find out if your blood flow is blocked or reduced. These imaging tests can help diagnose conditions such as:
- Carotid arterial stenosis
- Deep vein thrombosis
- Peripheral artery disease
- Venous insufficiency
Getting Ready for a Doppler Ultrasound
Depending on the type of Doppler ultrasound your provider orders, you may not be able to eat or drink for several hours before. If you smoke, avoid cigarettes or other nicotine products at least two hours before your test. Nicotine causes your blood vessels to narrow, which may affect your test results.
What to Expect During a Doppler Ultrasound
First, a radiologist or ultrasound technologist will put a gel on the skin of the area being tested. This gel helps sound waves travel between a transducer, which sends sound waves into your body, and your skin. As the transducer travels over your skin, moving blood cells will cause the pitch of the sound waves to change. The sound waves are recorded on a computer and made into graphs or pictures, depending on the type of Doppler ultrasound performed.
The test usually takes 30 minutes to an hour to complete.
After your test, the radiologist or technologist will send your results to a provider. The provider will review your results and, if necessary, alert you of any next steps.