OSF Saint James - John W. Albrecht Medical Center

Virtual Colonography CT

Virtual Colonography CT, or virtual colonoscopy, is a minimally-invasive procedure for identifying precancerous polyps in the colon (large intestine) by using low dose radiation CT scanning to obtain an interior view of the colon.

Polyps are growths that begin in the inner lining of the intestine and can grow then turn into cancers. The goal of Virtual Colonography CT is to find the growths so that they can be removed before they have a chance to develop into cancer.

For Virtual Colonography CT, a computer generates a detailed 3-D model of the abdomen and pelvis, which the physician (radiologist) uses to view the bowel in a way that simulates traveling down the colon.

This is why the procedure is often called a virtual colonoscopy. Two dimensional (2-D) images of the inside of the colon as well as the rest of the abdomen and pelvis are obtained and reviewed at the same time.

What to expect

Virtual Colonography CT is similar to a conventional colonoscopy, but no sedation is required and patients can resume normal activity immediately following the test with this virtual procedure.

The benefits of Virtual Colonography CT include:

  • a markedly lower risk of bowel perforation, no sedation required
  • clearer and more detailed images are provided by virtual technology
  • the physician can see past narrowing of bowel and any obstructions
  • can detect abnormalities on outside colon wall
  • less costly than a colonoscopy
  • tolerated well by patients
  • no radiation remains in the patient’s body after the exam
  • can be done immediately after failed colonoscopy (called Diagnostic Virtual Colonography CT)

Polyps cannot be removed during Virtual Colonography CT as they can in a colonoscopy.