Virtual Colonoscopy (Computed Tomography Colonography)
DESCRIPTION
Virtual colonoscopy (i.e., CT colonography) is an imaging procedure involving the use of spiral (helical) CT scanning and computers to produce a three-dimensional colonoscopic visualization of the colon and rectum. Some studies have suggested that this technique may be an attractive alternative to existing screening tests for colorectal cancer, since it is considered relatively safe and minimally invasive.
The procedure generally involves four steps: bowel cleansing, pneumocolon (air enema), spiral CT scanning and computer processing of the spiral CT images. With a virtual colonoscopy it is not possible to remove polyps or perform a biopsy. If a potential problem is found an additional procedure such as a conventional colonoscopy is needed.
POLICY
Virtual colonoscopy (i.e., computed tomography colonography) for the diagnosis of colorectal cancer is considered medically necessary if the medical appropriateness criteria are met. (See Medical Appropriateness below.)
Virtual colonoscopy (i.e., computed tomography colonography) for screening for colorectal cancer every five years is considered not medically necessary.
MEDICAL APPROPRIATENESS
Virtual colonoscopy (i.e., computed tomography colonography) for the diagnosis of colorectal cancer is considered medically appropriate if ANY ONE of the following criteria are met:
Individuals who have failed conventional colonoscopy (e.g. due to a known colonic lesion, structural abnormality or technical difficulty)
Individuals on anticoagulants who cannot have the anticoagulation withheld
Individuals with severe medical conditions that preclude conventional colonoscopy.
Individuals who have met the criteria for conventional colonoscopy but conventional colonoscopy is medically contraindicated
IMPORTANT REMINDER
We develop Medical Policies to provide guidance to Members and Providers. This Medical Policy relates only to the services or supplies described in it. The existence of a Medical Policy is not an authorization, certification, explanation of benefits or a contract for the service (or supply) that is referenced in the Medical Policy. For a determination of the benefits that a Member is entitled to receive under his or her health plan, the Member's health plan must be reviewed. If there is a conflict between the Medical Policy and a health plan, the express terms of the health plan will govern.
ADDITIONAL INFORMATION
Intravenous contrast is not usually used for routine computed tomography colonography (CTC), however the American College of Radiology (ACR) states that “a contrasted diagnostic computed tomography colonography (CTC) study may be useful in some patients after incomplete endoscopy to characterize indeterminate colonic masses or to better visualize colonic segments with excess fluid.”
A large comparative study has shown that computed tomography colonography (CTC) produced similar rates of detection for advanced neoplasia as conventional colonoscopy and is an effective method for colorectal screening. Although these results support the efficacy and safety of CTC for colorectal cancer screening, there are only limited follow-up data available so far for patients who underwent CTC and opted to have follow-up surveillance screening for polyps 6 to 9 mm in size. In addition, specific criteria needs to be developed to ensure that physicians are adequately trained and quality metrics for programs are in place.
Published evidence of well-designed studies in peer review journals is insufficient to determine whether the use of virtual colonoscopy (Computed Tomography Colonography) would improve population screening. The availability of literature consists of survey studies, patient satisfaction studies, and focus group studies. It is unclear how such studies provide a sufficient base of evidence to demonstrate that population adherence to colon cancer screening would improve.
SOURCES
American College of Radiology. (2009). 2010 CPT® code update. Retrieved August 17, 2010 from http://www.acr.org/Hidden/Economics/FeaturedCategories/Pubs/coding_source/archives/SeptOct09/2010CPTCodeUpdate.aspx.
Barish, M. A., Zalis, M. E., & Harris, G. J. (2006, June). CT colonography: Current status and economics. Retrieved August 17, 2010 from http://www.imagingeconomics.com/issues/articles/2006-06_03.asp.
BlueCross BlueShield Association. Medical Policy Reference Manual. (8:2009). Virtual colonoscopy/CT colonography (6.01.32). Retrieved December 28, 2010 from BlueWeb. (23 articles and/or guidelines reviewed)
Kim, D. H., Pickhardt, P. J., Taylor, A. J., Leung, W. K., Winter, T. C., Hinshaw, J. L., et al. (2007). CT colonography versus colonoscopy for the detection of advanced neoplasia. The New England Journal of Medicine, 357 (14), 1403-1412.
Levin, B., Lieberman, D. A., McFarland, B. Smith, R. A., Brooks, D., Andrews, K. S., et al. (2008). Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: A joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology. CA, 58 (3), 130-160.
ORIGINAL EFFECTIVE DATE: 8/1/2001
MOST RECENT REVIEW DATE: 1/28/2011
ID_MS; BA
Policies included in the Medical Policy Manual are not intended to certify coverage availability. They are medical determinations about a particular technology, service, drug, etc. While a policy or technology may be medically necessary, it could be excluded in a member's benefit plan. Please check with the appropriate claims department to determine if the service in question is a covered service under a particular benefit plan. Use of the Medical Policy Manual is not intended to replace independent medical judgment for treatment of individuals. The content on this Web site is not intended to be a substitute for professional medical advice in any way. Always seek the advice of your physician or other qualified health care provider if you have questions regarding a medical condition or treatment.
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