Positron Emission Tomography (PET Scan)

What Is It?

A positron emission tomography, or PET, scan is an imaging technique that uses radioactive tracers attached to sugar molecules. The scan can detect changes in the body's metabolism and chemical activities. A PET scan is often done in conjunction with a CT scan. The combination provides a color-coded image of the body's structure and function.

During a PET scan, the sugar molecules with the attached radioactive tracers are injected into a vein. Once the substance enters the body, it travels through the bloodstream to the body's organs. Areas in the body that have a higher rate of metabolism use more sugar. So these areas pick up the sugar molecules more readily than normal.

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