New-generation narrow band imaging improves visibility of polyps: a colonoscopy video evaluation study.

Background: The benefits of narrow band imaging (NBI) in colorectal polyp detection remain questionable. Previous NBI has poorer brightness and resolution than white light (WL). However, recently these factors were improved by the new-generation video processor system (EVIS LUCERA ELITE) in comparison with the previous system (EVIS LUCERA SPECTRUM). The aim of this study was to investigate whether NBI with EVIS LUCERA ELITE could improve the visibility of colorectal polyps compared to WL.
Methods: We analyzed prospectively 240 colorectal polyps (group 1: ELITE with CF-HQ290 scope, 80 polyps; group 2: ELITE with PCF-Q260AZI scope, 80 polyps; group 3: SPECTRUM with PCF-Q260AZI scope, 80 polyps) whose videos were recorded using NBI and WL at Kyoto Prefectural University of Medicine. The videos were evaluated in a randomized order by three experts and three non-experts. Each polyp was assigned a polyp visibility score from 4 (excellent visibility) to 1 (poor visibility). The polyp visibility scores in each mode and their relationship to the clinical characteristics were analyzed.
Results: The mean polyp visibility scores of NBI with ELITE system were significantly higher than those of WL (ELITE with CF-HQ290: 3.14 ± 0.87 vs. 2.75 ± 0.98, p < 0.0001, ELITE with PCF-Q260AZI: 3.03 ± 0.92 vs. 2.83 ± 0.93, p = 0.0006). Conversely, the mean polyp visibility score of NBI using SPECTRUM system with PCF-Q260AZI was significantly lower than WL (2.75 ± 1.06 vs. 3.05 ± 0.92, p < 0.0001).
Conclusions: Our study showed that NBI using EVIS LUCERA ELITE improved polyp visibility.