How to Prepare for a PET/CT Scan

1-2 days prior to your scheduled test, someone from our center will contact you to go over specific instructions.  Please inform us at that time if you are taking any medications.  It is extremely important to inform us if you are diabetic.

  • Do not eat or drink anything except water for 5 hours prior to your exam.  This includes gum and mints.
  • You may take your normal medications with water only.
  • It is very important that you arrive on time for your appointment.
  • Wear loose fitting, comfortable clothing.
  • Inform the technologist if you might be pregnant or if you are breast feeding.
  • Plan on being at our facility for 1 1/2 to 2 hours.
How a PET/CT Scan is Performed

Before the scan, you’ll get tracers through a vein in your arm, through a solution you drink, or in a gas you inhale. Your body needs time to absorb the tracers, so you’ll wait about an hour before the scan begins.

Next, you’ll undergo the scan. This involves lying on a narrow table attached to a PET/CT machine, which looks like a giant letter “O.” The table glides slowly into the machine so that the scan can be conducted.

You’ll need to lie still during the scan. The technician will let you know when it is that you need to remain still. You may be asked to hold your breath for short periods. You’ll hear buzzing and clicking noises during the test.

When all the necessary images have been recorded, you will slide out of the machine. The test is then complete.

After a PET/CT Scan

After the test, you can go about your day as normal unless your doctor gives you other instructions. Generally, all tracers leave your body after six hours.

Your physician will receive the results of your PET/CT scan within 24 to 48 hours.

What to Expect During Your PET/CT Scan
Check In

a small amount of paperwork needs to be completed


your medical history will be reviewed


a small amount of radioactive glucose will be given through an IV injection


you will be required to lie as still as possible for around 35 minutes

Images Sent to Your Doctor

your doctor will receive images and results once our radiologist has reviewed your scan

Frequently Asked Questions
Positron Emission Tomography (PET) is a powerful imaging technique that aids physicians in the diagnosis and treatment of many diseases, particularly cancer. A PET scan is a non-invasive test that provides your physician with a complete picture of how organs and tissues are functioning, making it easier for your doctor to diagnose problems, determine the extent of disease, prescribe treatment and track progress.1
Positron Emission Tomography (PET) and Computed Tomography (CT) scans are both standard imaging tools that physicians use to pinpoint disease states in the body. A PET scan demonstrates how organs and tissues are functioning at a very early stage in a disease, often before structural changes take place. The CT scan provides information about the body's anatomy, such as size, shape and location. By combining these two scanning technologies, a PET/CT scan enables physicians to more accurately diagnose and identify cancer, heart disease and brain disorders.1
A single PET or PET/CT exam can provide information that once would have required several medical studies and possibly surgery. PET scans are most often used to help the physician detect cancer and monitor response to treatment. PET scans are also used to evaluate heart disease and neurological conditions.
PET scans provide the physician with valuable information. For cancer patients it may help specialists understand the extent of disease, guide the most effective therapy, and then help evaluate if the treatment is effective. PET scans aid in the diagnosis of heart disease and neurological diseases. This type of imaging may show changes much earlier than other imaging tests like CT or MRI.
The risks associated with a PET scan are very slight. The amount of radiation is low and the radiopharmaceutical decays quickly so there is no detectable radioactivity after a few hours. In addition to the radioactive decay, the remaining radiopharmaceutical is eliminated from the body through urine. Family members are not at risk for exposure since most of the radioactivity has left the body or decayed before the patient has left the center. The physician providing you with the PET scan will explain any associated risks and benefits from the PET or PET/CT exam.2
Upon arrival at the imaging center you will receive an injection of radiopharmaceutical, which will take approximately 60 minutes to distribute throughout your body. You will be asked to empty your bladder and then lie down on the scanner bed. The scan takes approximately 15-35 minutes, depending upon the type of scan you are having and the type of scanner being used. It is important that you lie still during this process. If you need pain medication please bring it with you. You should plan on being at the imaging facility for approximately 2 to 3 hours.
Radiopharmaceuticals are used in a wide variety of Nuclear Medicine and PET exams to image and measure how the body functions. In PET imaging the most commonly used PET radiopharmaceutical is a radioactive form of glucose that allows doctors to image and measure how cells in the body use glucose for fuel. Different diseases increase or decrease the amount of glucose used.
Once the PET scan is complete, you will be able to leave the imaging facility.
Ask the physician providing the scan to describe any potential side effects.
The PET scan is interpreted by a trained nuclear medicine physician or radiologist and results are usually sent to the referring physician within 24-48 hours. You should contact your doctor to discuss the results.
If you are under a physician's care, you should follow your physician's recommendations for frequency of PET scans.
PET scans offer unique information about an organ's function that can show a physician signs of disease.
The only pain involved is the needle prick when you receive the radiopharmaceutical injection, which does not differ from any other type of injection.
Many PET scans are covered by private insurance and Medicare; pre-authorization may be needed and is advised.
  1. Society of Nuclear Medicine PET Center of Excellence. PET Professional Resources and Outreach Source PET Scans: Get the Facts. June 2009. 
  2. Radiological Society of North America, Inc. and American College of Radiology. April 2012.
Downloadable Files

For your convenience, the following files have been made available to download.  You will need Adobe PDF Reader or a compatible program to open and print the files.

Registration Form


Consent Form


HIPAA Privacy Notice


Grievance Protocol