METHODS: This observational study reviewed consecutive patients undergoing colorectal ESD from January 2021 to June 2025. Therapeutic outcomes of 72 ACI cases were compared with 505 white light imaging (WLI) cases. The primary outcome of this study was the mean number of intraoperative bleeding (IB) events during ESD between cases with ACI and those with WLI. The secondary outcomes were various therapeutic outcomes of ESD. Additionally, fifteen endoscopists from four countries (seven experts, eight non-experts) evaluated the visibility in ACI and WLI images during ESD using a four-point scale (Score 1 = poor to Score 4 = excellent).
RESULTS: Among 72 cases (mean age: 67.3 ± 11.9 years, male proportion: 48.6%), the en bloc resection rate was 98.6%. The ACI group showed fewer IB events than the WLI group (2.0 ± 2.5 vs 2.7 ± 3.4, p = 0.040), significant only among non-experts (1.5 ± 2.0 vs. 2.6 ± 3.1, p = 0.009). Regarding image evaluations, ACI achieved higher visibility scores (median [interquartile]) for vessels (4 [3-4] vs. 3 [2-3], p