Virtual colonoscopy is generally safe. Risks include:

  • Tear (perforation) in the colon or rectum. The colon and rectum are inflated with air or carbon dioxide during the test and this carries a small risk of causing a tear.
  • Exposure to a low level of radiation. Virtual colonoscopy uses a small dose of radiation to create the images of your colon and rectum. Doctors use the lowest dose of radiation possible to create a clear image. Generally this is about the same as the amount of natural radiation you might be exposed to in two years, and much less than the amount used for a diagnostic CT scan.
Sept. 23, 2017
  1. AskMayoExpert. CT colonography. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2016.
  2. Bibbins-Domingo K, et al. Screening for colorectal cancer: US Preventive Services Task Force recommendation statement. JAMA. 2016;315:2564.
  3. Johnson CD, et al. Computed tomographic colonography (virtual colonoscopy): A new method for detecting colorectal neoplasms. Endoscopy. 1997;29:454.
  4. Hara AK, et al. Detection of colorectal polyps by computed tomographic colography: Feasibility of a novel technique. Gastroenterology. 1996;110:284.
  5. Colorectal cancer screening. Fort Washington, Pa.: National Comprehensive Cancer Network. http://www.nccn.org/professionals/physician_gls/f_guidelines.asp. Accessed Aug. 24, 2017.
  6. Virtual colonoscopy. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/diagnostic-tests/virtual-colonoscopy. Accessed Aug. 24, 2017.
  7. Riggin EA. Allscripts EPSi. Mayo Clinic, Rochester, Minn. Jan 31, 2017.