Positron Emission Tomography & Computed Tomography (PET/CT) Scanning PET imaging (Positron emission tomography) or a PET scan, is a type of nuclear medicine imaging. A PET/CT scan uses a very small amount of radioactive material to show differences between healthy and diseased 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. Nuclear medicine imaging procedures are noninvasive and, with the exception of intravenous injections, are usually painless medical tests that help physicians diagnose and evaluate medical conditions. PET/CT scans produce diagnostic images, which can be used to evaluate a variety of diseases, such as: Evaluating the brain for: » Alzheimer’s disease » Brain tumors » Seizure disorders » Detecting cancer » Preparing cancer treatment planning CT imaging uses special x-ray equipment, and in some cases a contrast material, to produce multiple images or pictures of the inside of the body. These images can then be interpreted by a radiologist on a computer monitor as printed images. CT imaging provides excellent anatomic information. Today, most PET scans are performed on instruments that are combined PET and CT scanners. The combined PET/CT scans provide images that pinpoint the location of abnormal metabolic activity within the body. The combined scans have been shown to provide more accurate diagnoses than the two scans performed separately.