Second Examination of the Right Colon Using Narrow-Band Imaging Increases Adenoma Detection Rates in the Right Colon: A Multicenter, Randomized Controlled Trial

Abstract

Background/Aims Repeat examination of the right colon increases adenoma detection rates (ADRs) in the right colon. This study aimed to investigate whether a second examination of the right colon using narrow-band imaging (NBI) increases ADRs in the right colon compared with repeat examinations using white light imaging (WLI).

Methods Consecutive patients with routine indications for colonoscopy were enrolled and randomly assigned to two groups. The control arm underwent two repeat forward examinations of the right colon using WLI only (repeat-WLI group), and the intervention arm underwent the first examination of the right colon using WLI and the second examination using NBI (WLI-NBI group). Lesions detected during the first and second examinations in each group were analyzed. The primary outcome was ADR in the right colon.

Results A total of 476 colonoscopies were analyzed, including 240 and 236 in the repeat-WLI and WLI-NBI groups, respectively. The overall ADR in the right colon was significantly higher in the WLI-NBI group than that in the repeat-WLI group (27.1% vs. 17.9%; p = 0.022). The number of adenomas per colonoscopy in the right colon was also significantly higher in the WLI-NBI group than in the repeat-WLI group (mean number of adenomas, 0.36 vs. 0.24; p = 0.042). However, there were no significant differences in the detection rates of advanced adenomas and sessile serrated lesions between the WLI-NBI and repeat-WLI groups (advanced adenoma, 4.7% vs. 2.9%; sessile serrated lesion, 2.5% vs. 3.3%).

Conclusion A second forward examination of the right colon using NBI increased ADRs in the right colon.