Amber-red color imaging in third-space endoscopy and ESD: preliminary Western experience

ACI rendered the submucosa light blue, clearly separated from pale-pink mucosa and white muscularis, improving plane recognition and spatial orientation (notably during entry, tunnel expansion, and myotomy). ACI displayed subtle and deeper vessels in red with greater definition, supporting anticipatory coagulation and improving dissection accuracy. In gastric and rectal ESD, the dissection plane appeared more evident, especially in narrow/fibrotic planes, reducing the risk of inadvertent injury to muscle and the submucosal flap. All five cases were completed without adverse events. Limitations: Very small, single-operator, qualitative series; no prespecified procedural metrics or formal visibility measures; limited generalizability. Findings are hypothesis-generating, not hypothesis-testing. Conclusion: ACI appears promising for spatial orientation, vessel anticipation, plane maintenance, and dissection accuracy in third-space endoscopy/ESD. Prospective, multi-operator studies with predefined endpoints (dissection time, bleeding burden/hemostasis attempts, R0/curative resection, adverse events) and objective visibility/contrast metrics, stratified by organ and fibrosis grade, are warranted.