Comparing the ADR With Air Insufflation, Water Immersion and Water Exchange During Two-endoscopist Colonoscopy

Interval (missed) cancers and lower than expected mortality reduction of proximal colon
cancers in the United States and elsewhere after screening colonoscopy drew attention to
quality indicators. Missed adenomas which are more likely to be in the proximal colon may be
contributing factors. An independent predictor of the risk of interval cancers is adenoma
detection rate. In pilot observations, the investigators showed that water exchange enhanced
adenoma detection in the right colon (cecum to hepatic flexure). This prospective,
randomized controlled trial will compare water exchange with water immersion and traditional
air insufflation in patients undergoing colonoscopy. The investigators test the hypothesis
that compared with air insufflation and water immersion, water exchange produces a
significantly higher adenoma detection rate in the right colon