What should you expect?
No special preparation is needed for this test. If you smoke, you may be asked to stop smoking leading up to the test.
Gel will be placed on the skin of your arm or leg, over the area being tested.
There are two types of ultrasound:
One is a simple one-dimensional beam that detects movement by making a swishing sound. A hand-held device is pushed against your skin in the area being tested. Sound waves are sent into the body and bounce back to the machine. This is used to detect blood flow in arteries that may be narrowed. It may also be used to check for blood flow in veins that the doctor is concerned about.
The other technique makes a two-dimensional image. The ultrasound machine has a hand-held instrument called a transducer, which 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 structures in the body and echo back to the transducer. The echoes are converted to images that are shown on a screen. The doctor examines the images on the screen. He may make a photograph of them as well.
You will be able to leave after the test is done. The procedure will take 30 minutes to 1 hour.