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Computed Tomography

A Computed Tomography (CT) Scan, sometimes called a CAT scan, uses a series of x-ray images to produce a detailed picture of a part of your body, which could include bones, muscles, organs or blood vessels. Doctors use CT scans to quickly examine patients for internal injuries as well as diagnose muscle and bone disorders, detect and monitor disease and specify the location of a tumour, infection or blood clot. CT scans show more detail than regular x-rays.

A CT scanner is a large, donut-shaped machine. During your scan, you will lie on a table attached to the CT scanner. The CT scanner rotates to take x-rays of the part of your body that is being examined. Each rotation of the scanner takes less than a second. The information is sent to a computer that creates a 3D picture and shows it on a screen.

It is important that you lie very still during the scan because movement can make the picture blurry.

We offer the following types of CT scans:

  • Abdominal/pelvic CT scans
  • Chest CT scans
  • Head/neck CT scans
  • Musculoskeletal CT scans
  • Virtual Colonoscopy (CT Colonography)

Your appointment

  • Please arrive 15 minutes before your appointment. If you are late, your appointment may be rescheduled.
  • Bring a bag for your personal belongings during the exam.
  • You might need contrast dye, either intravenously or orally, before your CT scan. Contrast dye is a material that changes the way an imaging device, like a CT scan or x-ray, sees parts of your body. While generally safe, contrast dyes have a small risk of allergic reaction. If you know you are allergic to contrast dye, or have any issues with your kidneys, please tell the receptionist when booking your appointment. We may recommend taking medication such as steroid or antihistamine, before the exam. You would need to get a prescription for the steroid from your doctor.
  • If you have diabetes or kidney disease and require contrast dye, you will need blood work, including a serum creatinine test. Your referring doctor should make sure that you have had blood work done no more than three months before your CT scan. If you haven’t had a blood test done recently, or if your blood work doesn’t have the information we need, the receptionist or technologist may ask you to return to your clinic or your referring doctor to arrange for a blood test. Your CT scan will be rebooked accordingly.
  • If you require contrast dye, and a health care worker has had difficulties finding your veins for injections in the past, please let us know ahead of your appointment.
  • If you require a Hoyer lift to get from a wheelchair to a bed, or if you require more than one person to assist you when getting on and off a bed, please let us know ahead of your appointment.
  • Please see below for specific preparation instructions dependent on the type of CT scan you are getting. You should also follow any instructions given to you by your doctor or when you booked the CT scan.
  • If you wish to have another doctor copied on the results report, please let the receptionist know before your test.
  • The length of your appointment will depend on what kind of CT scan you are having. Most exams take from 10 to 30 minutes.
  • We do our best to stay on time. Unfortunately, your appointment may be delayed by unforeseen circumstances. We recommend that you come prepared for delays.
  • Note that female patients aged 10 to 55 will be asked if there is any chance of pregnancy.
  • You cannot wear jewelry for the scan. If we are scanning you above the neck, you may also have to take out your dentures, hearing aids, hairpins or wigs.
  • If necessary, you will be given a hospital gown to put on.
  • If you had to drink barium as a contrast agent or if you were injected with contrast dye, drink lots of fluid over the next 24 hours to help flush this out of your body, if your fluids are not restricted.
  • Call your referring doctor if you notice a change in how much you urinate, or if you notice any signs of an allergic reaction, such as hives, itching or swelling of your skin.
  • A report will be sent to your doctor(s) within 10 days.

Types of CT Scans

An abdominal/pelvic CT scan detects diseases of the small bowel, colon, and other internal organs.

Do not eat for four hours before the exam, but continue to drink plenty of fluids. Follow any other instructions given by your referring doctor or our booking office.

A chest CT scan examines abnormalities in the chest, and can be used to help diagnose and detect chest diseases and tumours.

Do not eat for three hours before the exam, but continue to drink plenty of fluids. Follow any other instructions given by your referring doctor or our booking office.

A head/neck CT scan is used to assess injuries and symptoms to do with the skull, brain, eyes, nasal passages, veins, arteries and tissue.

There are no eating restrictions, but drink plenty of fluids before your exam. Follow any other instructions given by your referring doctor or our booking office.

A virtual colonoscopy is used to produce images of the colon.

During a virtual colonoscopy, a technologist will insert carbon dioxide into your rectum with a catheter. You will be asked to lie on your back and then on your stomach for the exam.

Please refer to the preparation sheets from your preparation kit.

Find Us

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Department of Medical Imaging
5th Floor, 600 University Avenue
Toronto, Ontario, Canada M5G 1X5

Contact Us

Phone: 416-586-4800 ext.4418

Fax: 416-586-3180

Contact hours

Monday to Friday: 8:30 a.m. - 4:00 p.m.
Closed for lunch 12:00 - 1:00 p.m.

Outpatient hours of service

Monday to Friday: 8:00 a.m. - 5:30 p.m.

*This area is wheelchair accessible*