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PET scan: patient information

How to prepare for your PET/CT scan

If you need to reschedule or cancel the appointment then please call us at 416-480-4336. You will be with us for approximately 3 hours. The actual scan takes approximately 30-45 minutes.

PET/CT scan schedule

FOR 24 hours

Prior to your test:

EAT Foods High in Protein like Beef, Pork, Lamb, Poultry , Fish (all varieties-unbreaded), Shellfish, Eggs, Cheese, Cottage Cheese, Vegetables: Broccoli, asparagus, cauliflower, zucchini, spinach, mushrooms

AVOID Foods High in Carbohydrates Foods with sugars and artificial sweeteners, Cereals, Breads, Muffins, Pastas, Rice, Barley, Potatoes, Beans, Lentils

Do not do any strenuous exercise

For 5 hours

prior to your test:

DO NOT EAT. Do not chew gum or eat mints.

You may drink plain unflavoured water to stay hydrated. Do NOT drink anything else.

If you take insulin

For insulin diabetics a 4 hour fast is sufficient

Do not inject insulin within 3 hours of the test

Your sugar level must be below 11 mmol/L at your appointment time

If you experience symptoms (e.g. fast heart rate, headache) that suggest your blood sugar is low, take the appropriate measures as you normally would. Inform the technologist on your arrival.

If you take other medication

All medications can be taken on your normal schedule

If you are claustrophobic

If you are claustrophobic, you should request a light sedative from your physician

You will need someone to drive you home if you take this medication

Getting to my appointment

Sunnybrook Hospital 2075 Bayview Ave, Toronto, M4N 3M5

Check in at the Radiation Planning Department of the Odette Cancer Centre, TB100 in the T Wing Basement of the hospital

There are 2 sets of traffic lights off Bayview Ave going into Sunnybrook.

Turn into the hospital via the south lights.

Odette Cancer Centre is the 1st building on your right.

There is parking across from the building.

Please visit our website for more information:

How PET scans and Nuclear Medicine Work

PET (Positron Emission Tomography) scans are a type of Nuclear Medicine examination. Nuclear Medicine examinations are different from X-Rays. X-rays show what your body structure looks like. Nuclear Medicine examinations show how your body’s organs are actually working. First you swallow, inhale, or get injected with a substance called a radioactive tracer. This substance travels to the part of your body we want to examine. It gives off energy waves called gamma rays or positron emissions. A special camera builds these rays into pictures of your body indicating function or metabolic activity of different organs. The most common PET radioactive tracer is called FDG (Fludeoxyglucose). It is a substance like sugar.

What is a PET/CT SCAN?

PET scans are combined with a low dose CT (Computed Tomography) scan. The CT scan gives us detailed images of your anatomy or internal structures. This CT scan is used to enhance the PET image and help pinpoint the location of any abnormal tissue that may be seen on the PET scan. This low dose CT does not replace your regular CT scan. If your doctor has scheduled a CT scan for you in the CT department, you still need to do that.

For female patients

If you are breastfeeding or there is any chance that you are pregnant, tell the technologist before you have the injection. You may be required to have a pregnancy test prior to the injection.

What the scan is like

  • Be prepared to be here for 2 to 3 hours. You will be prepared for the test prior to the scan. The PET-CT scan itself takes approximately 30-45 minutes.
  • On your arrival we will measure your height, weight and measure your blood sugar level with a finger prick.
  • We will insert an IV line into a vein in your arm so that you are well hydrated and to provide an access to inject the radioactive sugar used for the scan. You should not experience side effects from the injection you receive.
  • You will rest in a dimly-lit room for approximately 30 minutes to allow the radioactive sugar time to circulate through your body.
  • In the PET-CT suite, we will position you on the scanner bed on your back with your arms positioned above your head.
  • You will be in full view of the technologists through a TV monitor and through a glass window.
  • The bed will move through the scanner slowly to acquire images of your body. It is important that you remain still during the scan. You might hear buzzing or clicking noises from the scanner. These are normal and you don’t need to worry.

After your scan

  • You can eat and drink as you normally would (unless you are going on to have another test that has special restrictions).
  • Drink extra fluids for the remainder of the day to help flush the radioactive tracer from your body.

PET and Nuclear Medicine Department

Sunnybrook Health Sciences Centre
2075 Bayview Ave
Toronto, ON, M4N 3M5