title: Risk of lens cloudiness during colorectal endoscopic submucosal dissection and ability of a novel lens cleaner to maintain and restore endoscopic view.
abstract: OBJECTIVE
  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.
  
  
  CONCLUSIONS
  Lens cloudiness during ESD was associated with submucosal fatty tissue. Effective lens cleaner should be used to prevent and clean lens cloudiness.
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Naohisa
authors.initials: N
authors.lastname: Yoshida
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Naito
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Hirose
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Ogiso
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kewin Tien Ho
authors.initials: KT
authors.lastname: Siah
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Inada
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Dohi
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kamada
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Katada
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Uchiyama
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Handa
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Takagi
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Konishi
authors.affiliation: Department of Gastroenterology, Asahi University Murakami Memorial Hospital, Gifu, Japan.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Yagi
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Itoh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020685:Colonoscopes; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000601:surgery*; D004210:Dissection / Q000379:methods*; D004867:Equipment Design; D004868:Equipment Failure; D005260:Female; D006801:Humans; D015994:Incidence; D007413:Intestinal Mucosa / Q000601:surgery*; D007564:Japan / Q000453:epidemiology; D007909:Lenses / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology*; D011446:Prospective Studies; D012307:Risk Factors; D012996:Solutions
chemical_list: D012996:Solutions
keywords: colorectal cancer; endoscopic gastrointestinal surgery; fatty tissue; lens; surfactant