Narrow-band imaging does not improve detection of colorectal polyps when compared to conventional colonoscopy: a randomized controlled trial and meta-analysis of published studies

Abstract

BackgroundA colonoscopy may frequently miss polyps and cancers. A number of techniques have emerged to improve visualization and to reduce the rate of adenoma miss.MethodsWe conducted a randomized controlled trial (RCT) in two clinics of the Gastrointestinal Department of the Sanitas University Foundation in Bogota, Colombia. Eligible adult patients presenting for screening or diagnostic elective colonoscopy were randomlsy allocated to undergo conventional colonoscopy or narrow-band imaging (NBI) during instrument withdrawal by three experienced endoscopists. For the systematic review, studies were identified from the Cochrane Library, PUBMED and LILACS and assessed using the Cochrane risk of bias tool.ResultsWe enrolled a total of 482 patients (62.5% female), with a mean age of 58.33 years (SD 12.91); 241 into the intervention (NBI) colonoscopy and 241 into the conventional colonoscopy group. Most patients presented for diagnostic colonoscopy (75.3%). The overall rate of polyp detection was significantly higher in the conventional group compared to the NBI group (RR 0.75, 95%CI 0.60 to 0.96). However, no significant differences were found in the mean number of polyps (MD -0.1; 95%CI -0.25 to 0.05), and the mean number of adenomas (MD 0.04 95%CI -0.09 to 0.17). Meta-analysis of studies (regardless of indication) did not find any significant differences in the mean number of polyps (5 RCT, 2479 participants; WMD -0.07 95% CI -0.21 to 0.07; I2 68%), the mean number of adenomas (8 RCT, 3517 participants; WMD -0.08 95% CI -0.17; 0.01 to I2 62%) and the rate of patients with at least one adenoma (8 RCT, 3512 participants, RR 0.96 95% CI 0.88 to 1,04;I2 0%).ConclusionNBI does not improve detection of colorectal polyps when compared to conventional colonoscopy (Australian New Zealand Clinical Trials Registry ACTRN12610000456055).

Electronic chromoendoscopy

“…[42][43][44][45] These analyses affirm the Cochrane review, demonstrating no significant difference between HD-NBI and HD-WLE in the detection of adenomas and polyps. One of these meta-analyses additionally compared polyp miss rates between HD-NBI and HD-WLE.…”

Improvement in the visibility of colorectal polyps by using blue laser imaging (with video)

“…19 Furthermore, another systematic review including 8 randomized, controlled studies showed that NBI did not improve the detection of colorectal polyps compared with WL. 20 However, the withdrawal time is an important confounding factor that may affect the validity of these studies. Withdrawal time is a difficult endoscopic factor to regulate because we are not able to control the speed of the colonoscope over a whole colonoscopic observation, compared with video studies when only a small segment of the whole colonoscopic observation is normally recorded.…”

Screening colonoscopy: What is the most reliable modality for the detection and characterization of colorectal lesions?

“…Six meta-analyses assessed the ADR of the NBI system compared with that of white-light colonoscopy (WLI). [24][25][26][27][28] None of them found any difference in adenoma, small adenoma (<10 mm) or diminutive adenoma (<5 mm) detection rates. Another meta-analysis revealed a sensitivity comparing with Lucera and Exera II systems (Olympus Medical Systems).…”