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PET scan

Positron emission tomography (PET) scan is a test that combines computed tomography (CT) and nuclear scanning.

During a PET scan, a radioactive substance called a tracer is generally injected into a vein (usually in the arm) but on occasion may be inhaled. The tracer usually is a substance (such as glucose) that can be used (metabolized) by cells in the body.

A PET scan is often used to evaluate cancer, such as of the lung or colon. It also can be used to evaluate the heart's metabolism and blood flow and examine brain function.

PET scan pictures do not show as much detail as computed tomography (CT) scans or magnetic resonance imaging (MRI).

By Healthwise Staff
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
Specialist Medical Reviewer Howard Schaff, MD - Diagnostic Radiology
Last Revised August 18, 2009

WebMD Medical Reference from Healthwise

Last Updated: August 18, 2009
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