Do Water-aided Techniques Improve Serrated Polyp Detection Rate During Colonoscopy?

Abstract

Background and Study Aims: The utility of water-aided techniques (WT): water exchange (WE) and water immersion (WI) have been studied extensively in the literature for improving colonoscopy outcome metrics such as adenoma detection rate. Serrated polyps owing to their location and appearance have a high miss rate. The authors performed a systematic review and meta-analysis of studies comparing WT with the standard gas-assisted (GA) method to determine if there was any impact on serrated polyp detection rate (SPDR) and sessile serrated polyp detection rate.Methods: The following databases were queried for this systematic review: Medline, EMBASE, Cochrane Library, CINAHL, and Web of Sciences. The authors only included randomized controlled trials (RCTs). The primary outcome was SPDR and secondary outcomes were sessile serrated polyp detection rate and cecal intubation rate. Risk ratios (RRs) were calculated for each outcome. A P-value <0.05 was considered to be statistically significant.Results: A total of 4 RCTs (5 arms) with 5306 patients (2571 in the GA group and 2735 in the WT group) were included. The SPDR was significantly increased for the WT group compared with GA (6.1% vs. 3.8%; RR, 1.63; 95% confidence interval, 1.24-2.13; P < 0.001; I 2 = 22.7%). A subgroup analysis for WE technique also demonstrated improved SPDR compared with the GA method (4.9% vs. 3.2%; RR, 1.57; 95% confidence interval, 1.15-2.14; P = 0.004; I 2 = 6.1%).Conclusions: WT, particularly, the WE method results in improved SPDR. This technique should be encouraged in a clinical setting to detect these polyps to prevent interval colorectal cancer.

Sessile serrated lesion detection rates continue to increase: 2008–2020

“…Finally, the technologies used by the Gastroenterology Division were upgraded numerous times during the study period (e. g., zoom magnification and narrow band imaging). Many of these technologies undoubtedly improved the ability to detect and resect SSLs 26 32 . However, newer scopes and monitors were never replaced en masse, but were instead replaced on a rolling basis across months and even years in some cases.…”

Intervenciones endoscópicas para mejorar la tasa de detección de lesiones serradas durante la colonoscopia

“…En lo referente a las técnicas basadas en agua, los 3 metanálisis que evaluaron su utilidad encontraron beneficio de su uso, siendo 2 de ellos de baja calidad de evidencia (15,16) y el otro de críticamente baja calidad (25) . Dentro de las 2 técnicas basadas en agua, la técnica de WE presenta mayor evidencia que la técnica de WI, validado en los metanálisis de Shao et al (25) y de Aziz et al (54) , así como en el ECA de Cheng et al (55) En la técnica de WE, hay una instilación y aspiración de agua durante la fase de inserción, lo que lleva a una limpieza mayor de la mucosa del colon. De hecho, se crea una turbulencia que remueve restos fecales residuales adheridos a la mucosa, mejorando la visualización de ésta.La mejora en la limpieza del colon durante la fase de inserción, vía la técnica de WE, minimiza las distracciones que se presentan al intentar limpiar el colon durante la fase de retirada, permitiendo al endoscopista concentrar su atención en la búsqueda de lesiones en la mucosa (58) .…”

Comparison of Right Colon Flat Polyp Detection Rate by Water Exchange Versus Water Immersion-pooled Results of Data File of 3 Published Reports

“…The results did not change after adjusting for mean withdrawal time and indication for colonoscopy. 27 In another systematic review with meta-analysis, 8 the question of whether WI and WE (water-aided group) improved the SPDR was addressed. A total of 4 RCTs (5 arms) with 5306 patients (2571 in the gas-assisted group and 2735 in the water-aided group were included.…”

“…In contrast, WI did not increase SPDR. 8 These 2 reports 8,27 involving thousands of patients established an undisputed and significant impact of WE on SPDR.…”

“…In 2021 a systematic review with meta-analysis suggested that water exchange (WE), but not water immersion (WI), significantly increased SPDR. 8 At present, endoscopic examination reveals the morphology (flat vs. polypoid) but not the histologic diagnosis of serrated pathology of the flat polyps in real-time. Nonetheless, the identification and removal of flat lesions is the best approach to maximize SPDR to minimize the development of interval cancers.…”