A positron emission tomography (PET) scan is a type of imaging study that can help doctors see what’s happening inside your body and how it’s working. This can help them understand how a disease is unfolding. A PET scan is different from an X-ray, CT, or MRI, which only show images of the body.
When you get a PET scan, your doctor will give you a radioactive substance called a radiotracer (or just “tracer”). The PET scanner can see where this tracer goes in your body. If it builds up in certain areas, that could be a sign of disease.
What does a PET scan machine look like?
A PET scan machine has a large, doughnut-shaped ring with a bed or table in the middle. When you he the scan, you lie down on the table, which slides into the hole of the machine. The scanner is big, but open, so it doesn’t completely enclose you the way many MRI machines do.
What does a PET scan show?
A PET scan shows how the organs and tissues in your body are working, including how well your heart is pumping blood, or if there’s unusual activity in certain areas that might be caused by disease, like cancer. This can help doctors understand if there’s a problem, even if it doesn’t show up on another type of scan.
What Is a PET Scan Used For?A PET scan can help doctors test for diseases, prepare for surgery, and see how well treatments are working. You might get one for several reasons, but they’re most often used with cancer, heart disease, and brain conditions.
PET scan for cancer
PET scans can show how much energy different cells in your body are using. Since cancer cells are more active than normal cells, the scan can pick up on their activity. Areas with cancer cells light up as bright spots on the images. A PET scan can often detect cancer before most other tests.
Besides cancer detection, your doctor may also use a PET scan to see if cancer has spread, check if cancer treatment is working, or determine if cancer came back after treatment.