Right-sided adenoma detection with retroflexion versus forward-view colonoscopy

Background: Colonoscopy and polypectomy can prevent up to 80% of colon cancer; however, a significant adenoma miss rate still exists, particularly in the right side of the colon. Objective: To assess whether retroflexion in the right side of the colon significantly improves the adenoma detection rate (ADR) over forward-view assessment. Design: Multicenter prospective cohort study. Setting: Three tertiary care public and 2 private hospitals. Patients: A total of 1351 consecutive adult patients undergoing elective colonoscopy. Intervention: Withdrawal from the cecum was performed in the forward view initially and identified polyps removed. Once the hepatic flexure was reached, the cecum was reintubated and the right side of the colon was assessed in the retroflexed view to the hepatic flexure. Main Outcome Measurements: ADR in the retroflexed view when compared with forward-view examination of the right side of the colon. Results: Retroflexion was successful in 95.9% of patients, with looping the predominant (69.6%) reason for failure. Forward-view assessment of the right side of the colon identified 642 polyps, of which 531 were adenomas yielding a polyp and ADR of 28.57% and 24.64%, respectively. Retroflexion identified a further 84 polyps of which 75 were adenomas, improving the polyp and ADR to 30.57% and 26.4%, respectively. Limitations: Observational study. Conclusion: Right-sided retroflexion was successful in most of our cohort with a statistically significant but small increase in ADR. Right-sided retroflexion is safe when performed by experienced endoscopists with no adverse events observed in this cohort.