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.
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, swallowed or inhaled as a gas and eventually 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.