Risk of lens cloudiness during colorectal endoscopic submucosal dissection and ability of a novel lens cleaner to maintain and restore endoscopic view.

Background and Aim: Generally, colorectal endoscopic submucosal dissection (ESD) cannot be carried out with severe lens cloudiness. We examined the occurrence of lens cloudiness during ESD as well as the efficacy of a novel cleaner for it.
Methods: This study was a prospective study compared to historical control. First, we analyzed 103 ESD cases using standard cleaner at the Kyoto Prefectural University of Medicine in 2012. Relationship between lens cloudiness and clinical characteristics of lesions was analyzed. Lens cloudiness was recorded as grade 0 (clear) to grade 2 (very unclear). Then, we recruited 92 consecutive patients who underwent colorectal ESD using the novel cleaner from August 2013 to July 2014. The cleaner was applied on top of the lens before procedure and ability to prevent lens cloudiness was tested. Additionally, the novel cleaner was injected from endoscopic channel into a space created by endoscopic hood and colonic wall in seven cases with grade 1 or 2 of lens cloudiness and the ability to clean lens cloudiness inside the colon was tested.
Results: Rate of severe lens cloudiness was 8.7%. Multivariate analysis showed that severe lens cloudiness was related with severe submucosal fatty tissue (P < 0.001). The novel cleaner had significantly less cloudiness cases compared to the standard cleaner (14.1% vs 33.0%, P = 0.002). Additionally, the novel cleaner enabled us to clean lens cloudiness in all seven cases.
Conclusion: Lens cloudiness during ESD was associated with submucosal fatty tissue. Effective lens cleaner should be used to prevent and clean lens cloudiness.
(© 2015 The Authors. Digestive Endoscopy © 2015 Japan Gastroenterological Endoscopy Society.)