PET/CT Scanning

Frequently Asked Questions

Select question:


Are there alternatives to PET?

Yes and no. There are other exams that can be performed. However, there is no other metabolic (biological) scanning technique other than PET at this time. CT and MRI, for example, both examine the anatomical (physical) structure. Therefore, they can be useful in determining the size and location of a tumor, but neither of them can determine whether a tumor is still active.

What do I need to do to prepare for the PET/CT scan?

The accuracy of your PET/CT scan depends on your body’s metabolic activity, which is controlled by the factors below. It is very important that you follow all of these instructions.

  • Nothing to eat or drink (except water) after midnight. If you have an afternoon appointment, you will receive specific instructions regarding breakfast. Only water and medications may be taken within 8 hours of the scan.
  • If you are diabetic you will receive specific instructions.
  • Do not chew gum, Nicorette gum, candy (including mints), or cough drops for at least 6 hours before your scan.
  • You may take any prescribed medications with water. If any of your medications must be taken with food ask your doctor whether you should take your morning dose without food or take it after the scan.
  • Unless you are on fluid restrictions for other reasons, drink at least 64 ounces of fluids the day before your exam including two 8 ounce glasses of water the night before your scan. Continue drinking water the day of your exam to prevent dehydration.
  • Do not perform any strenuous or vigorous activity (e.g. aerobics, jogging, golf, etc.) for at least 24 hours prior to the scan.
  • Sedation is rarely needed; however, if you are claustrophobic or tend to be extremely nervous and fidgety, consult your doctor. Please advise the secretary if a relaxing medication has been prescribed so that we can determine the best time for you to take it. Arrange to have someone drive you to and from ImageCare Medical Imaging.

Is a PET/CT scan painless?

The only pain involved is the needle prick when you receive the radiopharmaceutical injection which does not differ from any other type of injection.

What will happen when I arrive for my appointment?

When you arrive at ImageCare for your PET/CT, you will be registered by our office secretary and escorted to a quiet room where you will be asked a few medical history questions.

A technologist will obtain a small blood sample from a finger stick to check your blood sugar level. If it is elevated to levels over 200, it will be necessary to reschedule your exam. If you are diabetic be sure to notify the office secretary when your test is scheduled

The technologist will then inject a small amount of radioactive glucose (FDG) into your bloodstream. This glucose is called a “tracer” and will be distributed throughout your body. There are no side effects or allergic reactions to this injection.

What will happen during my appointment?

After your injection you will be asked to relax in a lounge chair in a quiet non-stimulating environment. You need to remain very still for about an hour before the scan will start. The PET scanner is similar in shape to a CT scanner and you will be made as comfortable as possible. Some people fall asleep during the procedure.

When the imaging is complete, the scanner will send the resulting information to a computer. The computer then generates a number of images that will be reviewed by a specially-trained radiologist. Your doctor will receive a detailed report of the findings in 2-3 days.

How long will I be at my appointment?

You can expect to be at ImageCare’s PET/CT Center for about 2 hours. The actual scan itself takes 20-30 minutes depending on what kind of scan you are having. Your family and friends will need to wait in the waiting room during your test.

How will I feel after my PET/CT scan?

You will feel fine after your PET scan. There are no side effects from the injection.