Positron Emission Tomography (PET)

Positron emission tomography (PET) is a test that uses a special type of camera and a Reference tracer Opens New Window (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 Reference IV Opens New Window) 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 do not show as much detail as Reference computed tomography (CT) scans Opens New Window or Reference magnetic resonance imaging (MRI) Opens New Window 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.

See pictures of a Reference PET scanner Opens New Window Reference Opens New Window and Reference PET scans of the brain Opens New Window Reference Opens New Window.

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