PET-CT Preparation

What is PET-CT?

PET/CT combines two state of the art imaging modalities. By monitoring glucose metabolism, PET provides very sensitive information regardless of whether a growth within the body is cancerous or not.  CT (computed tomography) meanwhile provides detailed information about the location, size, and shape of various lesions but cannot differentiate cancerous lesions from normal structures with the same accuracy as PET.

The combined PET/CT scanner merges PET and CT images together.  Every PET/CT scan at Lakes Radiology is reviewed and correlated by a board certified Nuclear Medicine radiologist at a daily session.

Patients referred for PET-CT scanning will be required to spend approximately two hours at Lakes Radiology.

Patients are first injected with a very small amount of the FDG radiotracer. The patient then waits approximately 45 – 60 minutes prior to scanning to allow for the FDG to adequately target and bind to possible cancer cells within the body, The actual scan takes approximately 35 – 45 minutes with the patient lying flat within the scanner.

How should I prepare?

You may be asked to wear a gown during the exam or you may be allowed to wear your own clothing.

Women should always inform their physician or technologist if there is any possibility that they are pregnant or if they are breastfeeding their baby. Ask the technologist for more information about pregnancy and breastfeeding related to nuclear medicine imaging.

You should inform your physician of any medications you are taking as well as vitamins and herbal supplements and if you have any allergies. Also inform your doctor about recent illnesses or other medical conditions.

Jewelry and other accessories should be left at home if possible, or removed prior to the exam because they may interfere with the procedure.

You will receive specific instructions based on the type of PET scan you are undergoing. Diabetic patients will receive special instructions to prepare for this exam.

What will I experience during and after the procedure?

Most nuclear medicine procedures are painless.

If the radiotracer is given intravenously, you will feel a slight pin prick when the needle is inserted into your vein for the intravenous line. When the radioactive material is injected into your arm, you may feel a cold sensation moving up your arm, but there are generally no other side effects.

When swallowed, the radiotracer has little or no taste. When inhaled, you should feel no differently than when breathing room air or holding your breath.

With some procedures, a catheter may be placed into your bladder, which may cause temporary discomfort.

It is important that you remain still while the images are being recorded. Though nuclear imaging itself causes no pain, there may be some discomfort from having to remain still or to stay in one particular position during imaging.

If you are claustrophobic, you may feel some anxiety while you are being scanned.

Unless your physician tells you otherwise, you may resume your normal activities after your nuclear medicine scan.

Through the natural process of radioactive decay, the small amount of radiotracer in your body will lose its radioactivity over time. In many cases, the radioactivity will dissipate over the first 24 hours following the test and pass out of your body through your urine or stool. You may be instructed to take special precautions after urinating, to flush the toilet twice and to wash your hands thoroughly. You should also drink plenty of water to help flush the radioactive material out of your body.

Who interprets the results and how do I get them?

A radiologist who has specialized training in nuclear medicine will interpret the images and forward a report to your referring physician.

To schedule an appointment at Lakes Radiology please call (305) 231-1115 or email us at