A Doppler ultrasound is a test that uses high-frequency sound waves to view the motion of fluids in the blood vessels.
Reasons for Test
Doppler ultrasound is used to:
View the flow of blood through vessels and/or the heart
View and evaluate blockages to blood flow, such as clots
Assess build-up of plaque inside a vessel
Monitor blood flow through repaired blood vessels such as
Examine a baby's blood flow during a pregnancy
In most cases, there are no complications with this test.
What to Expect
Prior to Test
Your doctor may do the following:
A physical exam
Blood or urine tests
In some cases your doctor may instruct you to:
Fast for 8-12 hours before the test. This will decrease the amount of gas in your intestines and make organs easier to see.
Have a full bladder before the test. You may need to drink 6 or more glasses of water without going to the bathroom.
smoking. Smoking can interfere with test results.
Description of the Test
You will lie on a table. Your doctor will put a gel on the skin over the area that will be examined. The gel helps the sound waves travel between the machine and your body.
The ultrasound machine has a hand-held instrument called a transducer. It looks like a microphone or wand. The transducer is pushed against your skin where the gel was applied. The transducer sends sound waves into your body. The waves bounce off your internal organs and echo back to the transducer. The echoes are changed into images that are shown on a screen. The doctor examines the images on the screen. Photographs of the images may be taken.
You may be asked to change positions or hold your breath during the exam.
General ultrasound. Radiology Info—Radiologic Society of North America website. Available at: https://www.radiologyinfo.org/en/info.cfm?PG=genus. Updated May 30, 2016. Accessed March 1, 2018.
Ultrasound imaging. US Food & Drug Administration website. Available at: https://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandProcedures/MedicalImaging/ucm115357.htm. Updated December 4, 2017. Accessed March 1, 2018.
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