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.
Subscribe to Harvard Health Online for immediate access to health news and information from Harvard Medical School.
- Research health conditions
- Check your symptoms
- Prepare for a doctor's visit or test
- Find the best treatments and procedures for you
- Explore options for better nutrition and exercise