A Doppler test is a noninvasive medical test that uses sound waves to show blood moving through blood vessels. It is named after Christian Doppler, a 19th-century physicist who discovered a way to measure sound waves reflected from moving objects. The test works by measuring sound waves that are reflected from moving objects, such as red blood cells, and is used to estimate the blood flow through blood vessels by bouncing high-frequency sound waves. There are different types of Doppler ultrasound tests, including color Doppler, spectral Doppler, and duplex Doppler.

A Doppler ultrasound can be used to help healthcare providers find out if you have a condition that is reducing or blocking your blood flow. It may also be used to help diagnose certain heart diseases. The test is most often used to check heart function, look for blockages in blood flow, and detect blood clots.

During the test, a sonographer, a specialist in ultrasound imaging technology, performs the test. The test may take 30 to 60 minutes, and depending on the reason for the test, you may lie on your back or side on an exam table, or you may sit up. The sonographer applies a small amount of gel to your skin, which helps the sonographer glide a small probe over the skin. It also helps sound waves travel.

The Doppler ultrasound is a safe, painless way for healthcare providers to assess the health of blood vessels and check for cardiovascular problems. The results of the test are available right away for your doctor to review, and they will let you know what all the images mean.