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PET Scan: Preparation and Procedure

PET imaging is a diagnostic imaging tool. PET imaging is a process by which the biologic functions of the body are able to be imaged. By using a small amount of a biological marker the PET scan procedure can assess areas of abnormal glucose metabolism in the body.

What is a PET Scan?

This change in the metabolism may be seen before a physical change can be seen on a CT or MRI. The latest advancement in imaging has combined the PET scan procedure with a CT scan (PET/CT) allowing areas of interest to be more accurately localized.

NorthShore University HealthSystem currently offers the PET/CT scan.

It is useful to help in diagnosis of:

PET Scan Procedure

  • At the beginning of the PET scan procedure, you will sit in a chair and receive an injection of a small amount of radioactive material called FDG in a vein in your arm.  This will not make you feel differently at all.
  • You will be asked to sit quietly for a period of time, usually about 30-60 minutes.   During this time you must sit and relax and will not be able to get up and walk around, talk to friends, or read.  This allows the tracer to travel throughout your body while it is in a relaxed state.
  • You will be asked to lie down on a table which will move you through the PET/CT scanner.   The machine has a larger opening than an MRI, and it does not make any sound.  A PET scan procedure takes about an hour to complete.

PET Scan Preparation & Diet

When scheduling a PET scan, it's important to keep in mind that your physician will require you to follow a strict PET scan preparation diet up to 12 hours before your appointment. A typical PET scan diet is as follows:

12 hours before your appointment:

  • You will be asked to eat a low carbohydrate diet. Foods that can be eaten include: meat, hard cheese, tofu, eggs, butter and vegetables with no starch. 
  • Some foods that are NOT allowed include: cereal, pasta, milk, breads and other sugars.
  • If you are scheduled in the late afternoon and can eat breakfast before the scan, it must be a low carbohydrate diet as well.

6 hours before your appointment:

  • For all PET scan diets, you will be asked to stop eating 6 hours before your appointment; however, you may continue to drink water.
  • You will also be asked to bring copies of any recent CT scans or MRI's done outside of NorthShore University HealthSystem.

How will I learn the results?

After the PET scan procedure, images will be checked by a physician. Shortly thereafter you will be made aware of the results.

Does insurance cover the cost of the test?

PET/CT imaging is usually covered by Medicare and private insurance companies.  Private insurance usually follow Medicare guidelines but many will cover other indications for a PET/CT scan.  Contact your insurance for further information.

Listed below are some of the indications that Medicare will cover for a PET/CT scan.