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Positron Emission Tomography (PET)

Positron emission tomography (PET) camera.gif is a test that uses a special type of camera and a tracer (radioactive chemical) to look at organs in the body. The tracer usually is a special form of a substance (such as glucose) that collects in cells that are using a lot of energy, such as cancer cells.

During the test, the tracer liquid is put into a vein (intravenous, or IV) in your arm. The tracer moves through your body, where much of it collects in the specific organ or tissue. The tracer gives off tiny positively charged particles (positrons). The camera records the positrons and turns the recording into pictures on a computer.

PET scan pictures camera.gif do not show as much detail as computed tomography (CT) scans or magnetic resonance imaging (MRI) because the pictures show only the location of the tracer. The PET picture may be matched with those from a CT scan to get more detailed information about where the tracer is located.

A PET scan is often used to evaluate cancer, check blood flow, or see how organs are working.

Why It Is Done

A positron emission tomography (PET) scan is done to:

How To Prepare

Tell your doctor if you have diabetes. If you take medicine to control diabetes, you may need to take less than your normal dose. Talk with your doctor about how much medicine you should take.

Tell your doctor about any medicines and herbal remedies you take. You may need to stop taking some medicines or change your dose before this test.

WebMD Medical Reference from Healthwise

Last Updated: July 28, 2011
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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