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A test to look into the rectum and colon that uses a long, flexible, narrow tube with a light and tiny camera on the end. The tube is called a colonoscope.

PubMed Health Glossary
(Source: NIH - National Institute of Diabetes and Digestive and Kidney Diseases)

What works? Research summarized

Evidence reviews

Carbon dioxide insufflation during colonoscopy: A meta-analysis

Bibliographic details: Miao ZG, Qi LN, Li LQ.  Carbon dioxide insufflation during colonoscopy: A meta-analysis. World Chinese Journal of Digestology 2011; 19(23): 2501-2505

CT colonography ("virtual colonoscopy") for colon cancer screening

Bibliographic details: Mark D.  CT colonography ("virtual colonoscopy") for colon cancer screening. Chicago, IL, USA: Blue Cross and Blue Shield Association, Technology Evaluation Center. TEC Assessment Program; 19(6). 2004

Oral sodium phosphate versus polyethylene glycol-electrolyte lavage solution for colonoscopy preparation: a systematic review

Bibliographic details: Li Y D, Wang Y P, Pan T, Tian L.  Oral sodium phosphate versus polyethylene glycol-electrolyte lavage solution for colonoscopy preparation: a systematic review. Chinese Journal of Evidence-Based Medicine 2005; 5(7): 555-561

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Summaries for consumers

Bowel cancer: Sigmoidoscopy and colonoscopy

In a colonoscopy, the doctor examines the entire large intestine for bowel polyps and potentially cancerous tissue. They can be then be removed directly. A sigmoidoscopy only examines part of the large intestine.In Germany, bowel cancer screening tests are intended for people between the ages of 50 and 75 who do not have a particularly increased risk of bowel cancer. The costs for a chemical stool test or a colonoscopy are covered by statutory health insurance in Germany.The costs for a sigmoidoscopy are not covered as part of the screening. But studies have shown that sigmoidoscopy screening can indeed lower the risk of getting bowel cancer and dying.

[Transparent Cap Colonoscopy versus Standard Colonoscopy to Improve Caecal Intubation]

Fourteen randomised controlled trials were included in the review comparing Colonoscopy with the Transparent Cap with Standard Colonoscopy in the investigation of gastrointestinal tract conditions. The findings of our work suggest that there is improvement in time to caecal intubation (which indicates that the colonoscopy is complete) when using the transparent cap compared with standard colonoscopy, although this is not statistically significant. We conclude that further research is required to assess the clinical significance of this result, especially considering that there have been no adverse events noted.]

Chromoscopic colonoscopy enhances polyp detection compared with conventional colonoscopy

Colonoscopy is a diagnostic test that enables small growths in the bowel (polyps) to be detected. These lesions can develop into cancer in approximately 5% of the cases. Although the test is the most sensitive test that exists for the detection of these growths, some may be missed. If a simple dye spraying technique (chromoscopy) is used with the colonoscopic test, the detection of these lesions may be enhanced. Several studies have examined the effect of chromoscopy on enhancing polyp detection but the data is inconsistent. This review investigated whether chromoscopy can enhance polyp detection compared with conventional colonoscopy.

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More about Colonoscopy

Photo of an adult

Also called: Endoscopy of the colon

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