The Effect of Right Colon Retroflexion on Adenoma Detection

Abstract

Background While colonoscopy with polypectomy can prevent up to 80% of colorectal cancers, a significant adenoma miss rate still exists, particularly in the right colon. Previous studies addressing right colon retroflexion have revealed discordant evidence regarding the benefit of this maneuver on adenoma detection with concomitant concerns about safety and rates of maneuver success. In this meta-analysis, we sought to determine the effect of right colon retroflexion on improving adenoma detection compared with conventional colonoscopy without retroflexion, as well as determine the rates of retroflexion maneuver success and adverse events. Methods Multiple databases including MEDLINE, Embase, and Web of Science were searched for studies on right colon retroflexion and its impact on adenoma detection compared with conventional colonoscopy. Pooled analyses of adenoma detection and retroflexion success were based on mixed-effects and random-effects models with heterogeneity analyses. Results Eight studies met the inclusion criteria (N = 3660). The primary analysis comparing colonoscopy with right-sided retroflexion vs. conventional colonoscopy to determine the per-adenoma miss rate in the right colon was 16.9% [95% CI, 12.5-22.5%]. The overall rate of successful retroflexion was 91.9% [95% CI, 86-95%] and rate of adverse events was 0.03%. Conclusions Colonoscopy with right-sided retroflexion significantly increases the detection of adenomas in the right colon compared with conventional colonoscopy with a high rate of maneuver success and small risk of adverse events. Thus, reexamination of the right colon in retroflexed view should be strongly considered in future standard of care colonoscopy guidelines for quality improvement in colon cancer prevention.

Real-time automatic detection system increases colonoscopic polyp and adenoma detection rates: a prospective randomised controlled study

“…Given the impact of colonoscopy on CRC incidence and mortality, technological advances such as full spectrum colonoscopy, retrograde viewing accessories, balloon colonoscope and endocuff-assisted colonoscopy have been introduced to improve the ADR by expanding the visual field 21–25. Methods aimed at improving the quality of colonoscopies such as minimal withdrawal time, split-dose bowel preparation and retroflexion in the right colon have also increased the ADR 26–30. Despite these advancements, polyps can still be missed.…”

Colonoscopic withdrawal time and adenoma detection in the right colon

“…However, the retroflexion in the RC did not improve the ADR and AADR in the RC, contrary with the findings in previous studies. [16,17,34] The total patient number of the retroflexion group was small and only 3 gastroenterologists performed the retroflexion, so it is hard to compare with previous retroflexion studies. Moreover, the sedative state did not improve ADR.…”

Is artificial intelligence the final answer to missed polyps in colonoscopy?

“…Another factor that would improve the ADR and reduce the AMR was the use of auxiliary techniques. There are a large number of auxiliary techniques, including second-pass colonoscopy[ 19 ], retroflexion in right-sided colon[ 20 ], water-aided colonoscopy[ 21 ], team detection approach (endoscopist and experienced nurse)[ 13 , 22 ], wide-angle endoscopy[ 23 ], high-definition endoscopy with or without a special imaging technique[ 24 - 26 ] and add-on devices[ 27 ], that have been reported to increase the ADR.…”