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Virtual Colonoscopy

A virtual colonoscopy is a gentler, minimally invasive CT alternative to conventional colonoscopy. The recorded CT images are assembled using a computer program creating both a 2 and 3 dimensional model that is examined by the radiologists for polyps or other abnormalities. If a polyp or mass is detected, a conventional colonoscopy will need to be performed to remove the lesion.

Am I eligible for a Virtual Colonoscopy?

The only conditions under which you would NOT be eligible for a virtual colonoscopy are if you have had a history of any of the following:

  • Ulcerative colitis
  • Crohn's disease

Preparation for Your Exam

You will be instructed to follow a 2 day low residual diet in conjunction with a 24 hour bowel prep kit available from the pharmacy. More detailed instructions will be provided to you by the scheduler when you make you appointment.

What happens in the CT room?

A small soft tipped rectal tube will be placed to allow the introduction of air into the colon. You will then be scanned, first lying face up then face down on the CT table. This dual positioning is performed in order to redistribute any stool or fluid which may remain within the colon despite the bowel preparation. It may also be determined by the radiologist whether the use of IV contrast would aid the interpretation of your virtual colonoscopy.

How long will it take?


You should be prepared to spend around 30 minutes in the CT Department the day of your exam. However, the CT exam requires no sedation and takes approximately 10-15 minutes to complete.

After The Exam

Because no sedation is used for a virtual colonoscopy, you may resume your normal daily routine after your exam. If you were given IV contrast for your exam, be sure to increase your fluid intake to help clear the material from your system.

Getting Your Results

Our radiologists will review the results of your CT scan with your doctor who will then explain them to you. Your doctor should have access to your exam results within 24 hours.