Virtual colonoscopy or computed tomographic colonography (CTC)

A CT scanner is used to take a series of X-rays of the colon and a computer to create a 3-D view. A radiologist then checks the images for suspicious polyps. If any polyps need to be removed, the patient must then have a regular colonoscopy.

Status: Decision completed

Why is CTC being reviewed?

CTC has been proposed as a less invasive alternative to conventional colonoscopy to screen for colorectal cancer, with the potential to induce more individuals to get screened. The issues are over concerns about safety, efficacy and cost. The screening would expose individuals to radiation, the accuracy of the imaging test is unknown, there is a need for additional procedures to remove and findings, and the cost of the test is greater and may need to be done more often.

Primary criteria ranking

  • Safety = Med
  • Efficacy = High
  • Cost = Med

Documentation