Comparing Right-Sided Colon Adenoma and Serrated Polyp Miss Rates With Water Exchange and CO 2 Insufflation: A...

Area of Science:

• Gastroenterology
• Endoscopy
• Colorectal Cancer Prevention

Background:

• Postcolonoscopy colorectal cancers often arise from missed adenomas and serrated polyps (SPs) in the right-sided colon.
• Water exchange (WE) enhances colon cleanliness and visibility, particularly in the right colon.
• WE may reduce the miss rates of adenomas and SPs in the right colon during colonoscopy.

Purpose of the Study:

• To evaluate the efficacy of water exchange (WE) in reducing the miss rate of adenomas and serrated polyps (SPs) in the right colon.
• To compare the combined right-sided colon adenoma miss rate (rAMR) and serrated polyp miss rate (rSPMR) between WE and CO2 insufflation.

Main Methods:

• A randomized trial involving 386 patients comparing WE versus CO2 insufflation during colonoscopy insertion.
• Polypectomies were performed during the first withdrawal up to the hepatic flexure.
• A second, blinded endoscopist re-examined the right-sided colon to determine the miss rate.

Main Results:

• WE significantly decreased the combined rAMR and rSPMR (22.2% vs 32.2%, P < 0.001) and rSPMR alone (22.5% vs 37.1%, P = 0.002).
• WE significantly increased the detection of SPs per colonoscopy in the right-sided colon (0.95 vs 0.50, P < 0.001).
• Multivariate analysis identified ≥2 SPs in the right colon as an independent predictor of rSPMR (OR, 3.47).

Conclusions:

• Colonoscopy insertion using water exchange (WE) significantly reduces the serrated polyp miss rate in the right colon.
• WE increases the detection of serrated polyps in the right colon compared to CO2 insufflation.
• WE is a valid alternative to CO2 insufflation for colonoscopy insertion, improving adenoma and SP detection.