Ultrasound - Doppler


A Doppler ultrasound study is a test which uses sound waves to examine the structures inside the body and to evaluate blood flow at the same time. With this test problems with the veins can be detected.


You will be asked to lie on your back with your head elevated slightly. A gel will be spread on your arms or legs on the area to be examined. A hand-held instrument, called a transducer, is used in the test. It looks like a microphone, and sends and receives silent, high frequency sound waves.

The person who does the test, the sonographer, or Radiologist will move the transducer down the length of the arm or leg. He will be listening, looking, and putting slight pressure on the vein. The arm or leg may need to be lightly squeezed at various times, to check for the flow of blood in the vein.
The transducer sends sound waves that pass through the skin into the body. They are reflected back to the transducer by the internal organs. These sound waves contain information that is changed into a picture of the area being examined. A picture of the image is recorded and interpreted by a radiologist.  To test the blood flow, a second method is used. When the sound waves strike moving objects (like red blood cells) the pitch of the sound is changed. The change in pitch can be displayed in several ways to evaluate blood flow within the body. An audible sound may be used, or the flow may be shown as a graphic or colordisplay.  There is no discomfort in this test.


Veins return blood to the heart. Impeded blood flow in the venous system causes pain, edema (swelling), tenderness, and increased limb size, usually at the calf, ankle, and lower thigh. Clots in the venous system may also cause pulmonary embolism (the lodging of a blood clot in the lungs) and other serious complications. 


For most Doppler exams, there is no preparation involved. Allow approximately 1 hour to completely finish your examination.


When your examination is completed, the radiologist will interpret the images. The results will be explained to you by your doctor. The reason for the test will depend on your symptoms.  Normal Results The organs examined appear normal.  What Abnormal Results Mean The meaning of abnormal results depends on the organ being examined and the type of problem. Talk to your health care provider if you have any questions or concerns.


There is no documented risk. No ionizing radiation exposure is involved.