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Your doctor has requested a FDG PET/CT scan. This booklet will answer some of the questions you may have.  

These instructions are not comprehensive. Two days before your appointment you are required to contact the booking office for instructions specific to you at 613-761-4831, option 8.

What is an FDG PET/CT Scan?  

A PET (Positron Emission Tomography) scan is a diagnostic test that uses a radioactive substance similar to sugar to detect tumors which use more glucose than normal tissue. We inject this product into a vein in your arm, give it time to circulate through your system, and then scan you in a special scanner to see where the radioactive substance is taken up within your body. 

This special scanner combines the PET scan with a CT (Computed Tomography) scan. The CT scan is performed first and gives us detailed images of your anatomy using x-rays. The PET scan is performed immediately after, on the same scanning bed. Together, the PET/CT can reveal diseased tissue that wouldn’t be seen on a CT scan alone.  

What is involved?  

The entire Procedure should take 2-2.5 hours. 

When you arrive, the technologist will explain the test to you and give you time to ask any questions you may have about the procedure.  

The technologist will set up an intravenous line and inject the radiotracer into a vein of your arm. There are no known side effects from this injection. Then, you rest in a special area for approximately 60 minutes, as this radioactive tracer circulates in your body. You will be given something to drink during the wait (either water or a special contrast drink for the CT scan).   

After the wait, the technologist will take you into the scanning room and have you lie on the scanning bed which will move in and out of the scanner. All you need to do is lie still and breathe normally for the entire scan. When the scan starts, we leave the room. We can still hear you and see you through a window and intercom. You might hear buzzing or clicking noises from the scanner during the scan. These sounds are normal, and you don’t need to worry. The duration of the scan typically lasts 20-40 minutes. 

Once the scan is complete, the technologist will show you out, and you can return home with no side effects from the procedure. 

Do I need to prepare for the scan?  

  • Bring your Health card. 
  • Do not eat or drink 6 hours before your appointment (including coffee, mints or chewing gum). Unflavored drinking water is permitted. 
  • Avoid vigorous exercise for two days before your appointment. Of note, you can go for a walk, but jogging is not permitted. 
  • If your medication(s) is safe to take on an empty stomach you may continue to do so. 
  • If you have recently received chemotherapy or radiation treatment, please contact the booking office. 
  • If you are diabetic, please pay particular attention to your diet the day before the scan. Check your blood sugar level often and try to keep it below 162 mg/dl (9.0 mmol/L). Make sure your glucose level is stable before the study. 
  • If you are presently taking antibiotics for an infection, please notify us immediately. 
  • Please leave all valuables at home. 
  • Please notify our booking office at the time of scheduling your appointment if you have any concerns regarding claustrophobia, lying still, require a mechanical lift for transfer to the imaging bed, have a language barrier or any other special needs, so that appropriate arrangements can be made ahead to provide you with the best possible care. 

Will it hurt?  

The blood glucose test and the insertion of the IV line may hurt. 

Is the radiation dangerous?  

The injection contains a small amount of radioactive tracer which emits gamma rays (these are similar to X-rays) which can be detected by our scanner. The radiation dose is very low and will disappear by itself after one day. The results of your scan will give your doctor useful information about your condition and will help them plan your treatment. The benefits of having the scan far outweigh any potential risk from the small radiation dose.  

Do I need to do anything after the scan?  

No special precautions are needed after the scan. If you are travelling across any borders within seven days after your scan, please ask us for further advice. Border crossings and airports have very sensitive radiation detectors which may pick up tiny amounts of radioactivity remaining within your body. We will give you a letter that you can show to customs officials at border crossings or airports. 

Is there anything I should tell the staff before the injection?  

Please tell us at time of booking if you are pregnant or breastfeeding.  

What about breastfeeding? 

Breastfeeding must be interrupted for a period of 12 hours after the exam, during which milk should be pumped and discarded. Prepare for your exam accordingly. 

How will I get the results of my scan?  

A specially trained doctor will examine the pictures. This is normally done soon after the end of the scan. A report is then sent to the doctor who asked us to do the scan. Your doctor will normally receive the report within one week. You will also have access to the report on MyChart as soon as it is released. 

If you have questions about the scan results or report, please contact your doctor directly. They are best able to interpret the report for you. 

Will this test cost me money? 

No. This test is paid for by the healthcare system. The test costs over one thousand dollars, so please notify the booking office at 613-761-4831, option 8 if you cannot make your appointment. 

What should I do if I cannot make my appointment? 

If you cannot make your appointment, it is important that you notify the department at 613-761-4831 as soon as possible. Failure to make your appointment results in wasting of expensive materials that are ordered especially for your appointment and also reduces availability to other patients. Missed appointments may also result in delays of your treatments. 

Directions and Parking 

General Campus  501 Smyth Road Main level Tel.: 613-761-4831, option 8 Hours: Mon. – Fri., 7:00 a.m. – 4:00 p.m.  Directions: From the main entrance, follow the signs on the main level (located at the public elevators). Patients may also ask for directions at the patient Information desk. 
Park in the parking garage which is located beside the main entrance just off Smyth Road. 

Parking instructions 

  • All parking lots are automated  
  • Take the parking ticket with you inside.  
  • When you have completed your appointment, you can pay by cash or credit card at one of our pay stations, or you can pay by credit card with express exit at the parking lot exit gates (the grace period after payment to leave facility is 20 minutes). 
  • Payment methods: 
    • Pay stations: Cash or credit card (Visa, MasterCard or American Express). 
  • Maximum parking fee is $13.00 

Visit The Ottawa Hospital’s website for additional directions and parking instructions and maps

Last updated on: May 17th, 2022