A positron emission tomography (PET) scan is an imaging test that helps reveal how your tissues and organs are functioning. A PET scan uses a radioactive drug (tracer) to show this activity. This scan can sometimes detect disease before it shows up on other imaging tests.

The tracer may be injected, swallowed or inhaled, depending on which organ or tissue is being studied. The tracer collects in areas of your body that have higher levels of chemical activity, which often correspond to areas of disease. On a PET scan, these areas show up as bright spots.

A PET scan is useful in revealing or evaluating several conditions, including many cancers, heart disease and brain disorders. Often, PET images are combined with CT or MRI scans to create special views.

June 09, 2017
  1. Javery O, et al. FDG PET or PET/CT in patients with pancreatic cancer: When does it add to diagnostic CT or MRI? Clinical Imaging 37;2013:295.
  2. Murphy JG, et al., eds. Positron emission tomography. In: Mayo Clinic Cardiology: Concise Textbook. 4th ed. New York, N.Y.: Oxford University Press; 2013.
  3. Ziessman HA, et al. Nuclear Medicine: The Requisites. 4th ed. Philadelphia, Pa.: Saunders Elsevier; 2014.
  4. Positron emission tomography — Computed tomography (PET/CT). Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=PET. Accessed Feb. 8, 2017.
  5. About nuclear medicine and molecular imaging. Society of Nuclear Medicine and Molecular Imaging. http://www.snmmi.org/AboutSNMMI/Content.aspx?ItemNumber=6433&navItemNumber=756. Accessed Feb. 8, 2017.
  6. About PET scans. American College of Radiology Imaging Network. http://www.acrin.org/patients/aboutimagingexamsandagents/aboutpetscans.aspx. Accessed Feb. 8, 2017.
  7. Longo DL, et al., eds. Neuroimaging in neurologic disorders. In: Harrison's Principles of Internal Medicine. 19th ed. New York, N.Y.: McGraw-Hill Education; 2015. http://accessmedicine.com. Accessed Feb. 10, 2017.
  8. FDA approves production of imaging agent that helps detect prostate cancer. U.S. Food and Drug Administration. http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm319201.htm. Accessed Feb. 2, 2017.
  9. Sobol I, et al. Contemporary mapping of post-prostatectomy prostate cancer relapse with C-choline positron emission tomography and multiparametric magnetic resonance imaging. Journal of Urology. 2017;197:129.
  10. Riggin EA. Decision Support System. Mayo Clinic, Rochester, Minn. Feb. 14, 2017.