Computed Tomography CT Colonography (Virtual Colonoscopy)

What is CT Colonography?

CT Colonography is a minimally invasive exam using CT (specialized X-ray) to view the colon. The purpose of this test is to screen for polyps and/or cancer. It is an excellent alternative for patients who have a tortuous or redundant colon.

Before the Procedure


Providing safe, quality patient care is our highest priority. For the best experience please properly prepare for your appointment:

  • It is extremely important for a quality exam to clean out your colon 48 hours before your CT scan. The ordering clinic will provide you with the laxative for this preparation.
  • Limit food intake to clear liquids such as broth, tea, or juice for 24 hours before your CT scan.
  • You will be able to resume your normal diet immediately following the exam.
  • FAILURE TO FOLLOW ANY OF THESE INSTRUCTIONS WILL RESULT IN RESCHEDULING EXAM.

During the Procedure

  • Two hours before the procedure, the CT technologist will give you an 8oz bottle of oral contrast, which contains a mixture of gastrografin and water.
  • CT technologist will bring you back to the exam room and ask you to undress from the waist down and change into a gown opening to the back. CT technologist will step out of the room for your privacy.
  • CT Technologist positions you on an exam table for CT/X-ray
  • A small flexible tube will be inserted 2 inches into your rectum which will allow air to be gently pumped into the colon so the doctor can get a clear view of the images.
  • The CT scanner will take images of your lower abdomen.
  • During the procedure you may feel fullness and cramping and may need to pass gas.

After the Procedure

  • Due to air being added to the colon you may experience an increased need to pass gas for a short while after your procedure.
  • You are able to resume your normal diet immediately following the exam.
  • A Radiologist is a doctor who reads your CT exam. They will get results to your ordering provider within 5 business days. Your ordering clinic will provide you with the results.

If you have any questions or concerns, please contact your provider.

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