PET Scan

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PET scans at UK HealthCare

PET scans can be repeated often during treatment to see how treatment is affecting the illness, and they may be used afterward to measure the results of treatment. UK HealthCare now offers PET scans several days a week.

What is a PET scan?

A positron emission tomography scan, or PET scan, is a painless test that looks at different parts of the body to see how they are working. It can show how much blood is flowing to an area of the body and how well the tissues in that area are using nutrients, such as oxygen. It can also show where medicines and chemicals go inside your body.

How does a PET scan work?

Before the scan begins you are given radioactive tracers, a dye in your IV or a gas that you breathe. The tracers are positive particles that give off signals when they combine with the negative electrons in your body. Electrons are tiny positive and negative electrical charges. These charges do many things, like help the body use food and medicine. Signals are picked up by the pet scanner and turned into pictures with different colors. Red signifies a lot of activity, yellow less activity, and green signifies even less activity.

Why do you need it?

PET scans are done for many reasons. Caregivers may need to see if you have an illness or injury, such as epilepsy or a stroke. The scan can show how far along an illness is, like Alzheimer's or Parkinson's disease. A PET scan may be done to help caregivers decide whether or not you have cancer. It can be repeated often during treatment to see how your treatment is effecting the illness, and it may be used afterward to measure the results of treatment.

Is it safe?

There are no known risks with a PET scan. Let your caregiver know if you are afraid of the test, if you are worried or if you have questions about your medicine, care, or the PET scan. You are exposed to very little radiation. The tracers are very strong but only live for a very short time. Even though the particles are positively charged you will not feel electrical shocks. Having a PET scan is safe and cannot hurt you.

Preparing for your PET scan

  • Do not eat or drink anything for 4 hours before the test.
  • Do not eat or drink anything for 4 hours before the test.
  • Ask your caregiver before taking any medicine on the day of the PET scan. These medicines include insulin, diabetic pills, high blood pressure pills or heart pills. Bring a list of your medicines or the pill bottles with you to the hospital.
  • Bring any papers your caregiver has given you to sign.
  • You may wear your glasses, but do not wear contact lenses the day of the scan.
  • Tell caregivers if you are afraid. Your caregiver may then give you medicine, a sedative (seh-duh-tiv), to help you relax during the test.
  • Tell your caregiver if you are, or think you may be, pregnant. The PET scan should not hurt your baby but your caregiver needs to know to help decide whether you should have the test.

A patient's guide to PET scans

Facts about PET scan 

  • PET is a powerful imaging technique that holds great promise in the diagnosis and treatment of many diseases, particularly cancer.
  • A PET scan is completely painless, with no known side effects.

Be prepared for your PET scan by asking your caregiver any questions you may have. You will be asked to lie down on the table of the PET scan machine. The PET scanner is shaped like a doughnut, and the table moves inside the hole when the test starts. The PET scanner slowly passes over your body, recording the movement of tracers in the different parts of your body. A caregiver will be in the same room with you, or in another room able talk to you.

After your PET scan

You may go home immediately after the test, unless you were given sedative medicine. If you received a sedative, you must have a responsible driver get you home and stay with you for several hours after the test.

Page last updated: 8/7/2015 4:11:47 PM