Positron Emission Topography (PET)
Positron emission tomography, also called PET imaging or a PET scan, is
a type of nuclear medicine imaging. Nuclear medicine is a branch of medical
imaging that uses small amounts of radioactive material to diagnose or
treat a variety of diseases, including many types of cancers.
How does a PET scan work?
Nuclear medicine procedures are noninvasive and usually painless medical
tests. They use radioactive materials called radiopharmaceuticals or radiotracers.
Depending on the type of exam you are undergoing, the radiotracer is either:
- Injected into a vein
- Inhaled as a gas
Eventually, the radiotracer accumulates in the organ or area of your body
being examined, where it gives off energy in the form of gamma rays.
This energy is detected by a device called a gamma camera, a (positron
emission tomography) PET scanner and/or probe. These devices work together
with a computer to measure the amount of radiotracer absorbed by your
body and to produce special pictures offering details on both the structure
and function of organs and tissue.
A PET scan measures important body functions, such as blood flow, oxygen
use, and sugar (glucose) metabolism, to help doctors evaluate how well
organs and tissues are functioning and how they may be affected by cancer.