PET Scan: Positron Emission Tomography

Tumors, memory issues, seizures, heart disease – we can look for these and the causes of these using a special imaging scan called positron emission tomography (PET). 

A PET makes images that show activity inside your body tissues. We can do that using a small amount of radioactive material. It goes to the part of your body that is most active. We then use a special machine to see where that radiation is.

PET can be done on your whole body or it can focus on just a part of it. For instance, we can focus on your:

We use PET to look for:

  • Tumors or their level of activity after treatment
  • Causes of memory problems
  • Causes of seizures
  • Heart disease

What Is a PET Scan Like?

Before Your PET Scan

Talks with your doctor about any conditions you have, any allergies, and what medications you take. If you're pregnant, make sure to let your doctor know. That can help us prevent problems with the scan.


  • Wear comfortable clothes.
  • Don't eat or drink anything except water at least 4 hours before your scan

During the PET Scan

We give you a small amount of radioactive substance. It travels through your blood to the area of the body we're scanning. It takes 30-90 minutes for the substance to be absorbed. When it's been absorbed, the can do the actual scan.

During the scan, you lie down on a table. The table is part of the PET machine. The table moves through the machine.

The machine can see and records the radioactivity that was injected earlier. A computer shows the images that the machine creates.

The scan lasts about 30-45 minutes. You may need to do some specific tasks before or during the test (for instance, during a heart PET scan, you may be asked to walk on a treadmill).

There shouldn't be any pain. If you're uncomfortable about being in closed or tight spaces, you may have some anxiety. Talk to your doctor ahead of time about that.

After the test, drink plenty of fluids. That helps the radioactive substance pass from your body.

Call your doctor if you have any unusual symptoms afterward, like a rash, itching, or trouble breathing. It could mean that you're having an allergic reaction to the radioactive substance.

Your Results   

We'll review the images and send the results to your doctor. Your doctor will go over the results with you.