title: A novel difficulty scoring system for laparoscopic liver resection.
abstract: Early on, laparoscopic liver resection (LLR) was limited to partial resection, but major LLR is no longer rare. A difficulty scoring system is required to guide surgeons in advancing from simple to highly technical laparoscopic resections. Subjects were 90 patients who had undergone pure LLR at three medical institutions (30 patients/institution) from January 2011 to April 2014. Surgical difficulty was assessed by the operator using an index of 1-10 with the following divisions: 1-3 low difficulty, 4-6 intermediate difficulty, and 7-10 high difficulty. Weighted kappa statistic was used to calculate the concordance between the operators' and reviewers' (expert surgeon) difficulty index. Inter-rater agreement (weighted kappa statistic) between the operators' and reviewers' assessments was 0.89 with the three-level difficulty index and 0.80 with the 10-level difficulty index. A 10-level difficulty index by linear modeling based on clinical information revealed a weighted kappa statistic of 0.72 and that scored by the extent of liver resection, tumor location, tumor size, liver function, and tumor proximity to major vessels revealed a weighted kappa statistic of 0.68. We proposed a new scoring system to predict difficulty of various LLRs preoperatively. The calculated score well reflected difficulty.
authors.affiliation: Department of Hepatobiliary and Pancreatic Surgery, Graduate School of Medicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ban
authors.forename: Minoru
authors.initials: M
authors.lastname: Tanabe
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Ito
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Otsuka
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nitta
authors.forename: Yuta
authors.initials: Y
authors.lastname: Abe
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: Toshio
authors.initials: T
authors.lastname: Katagiri
authors.forename: Chisato
authors.initials: C
authors.lastname: Takagi
authors.forename: Osamu
authors.initials: O
authors.lastname: Itano
authors.forename: Hironori
authors.initials: H
authors.lastname: Kaneko
authors.forename: Go
authors.initials: G
authors.lastname: Wakabayashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002983:Clinical Competence; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D010535:Laparoscopy; D008113:Liver Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Difficulty index; Difficulty score; Laparoscopic hepatectomy; Laparoscopic liver resection; Surgical difficulty