title: Clinical Utility of the Difficulty Scoring System for Predicting Surgical Time of Laparoscopic Liver Resection.
abstract: BACKGROUND
  Laparoscopic liver resection (LLR) has several problems, such as technical complexity and patient and tumor factors. A difficulty scoring system to preoperatively evaluate the difficulty of LLR was established at the second International Consensus Conference on Laparoscopic Liver Resection. The aim of this study was to explore the clinical usefulness of the difficulty scoring system for LLR.
  
  
  METHODS
  From January 2010 to June 2015, the records of 78 patients who had undergone LLR were retrospectively reviewed. The patients' data were used to assign a difficulty score, and the correlations between scores and surgical outcomes were investigated.
  
  
  RESULTS
  The mean surgical time was 256 minutes, and the mean blood loss was 168 mL. The difficulty score significantly correlated with surgical time and blood loss, but not with morbidity and postoperative hospital stay. Multivariate analysis showed that the difficulty score was an independent predictor of prolonged surgical time.
  
  
  CONCLUSIONS
  The difficulty score was found to be an effective predictor of surgical time for LLR.
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Hiroki
authors.initials: H
authors.lastname: Uchida
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Yukio
authors.initials: Y
authors.lastname: Iwashita
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Saga
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Hiroomi
authors.initials: H
authors.lastname: Takayama
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Kiminori
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Endo
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yada
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ohta
authors.affiliation: Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine , Oita, Japan .
authors.forename: Masafumi
authors.initials: M
authors.lastname: Inomata
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016063:Blood Loss, Surgical; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D010535:Laparoscopy; D007902:Length of Stay; D008113:Liver Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D011237:Predictive Value of Tests; D057234:Preoperative Period; D012189:Retrospective Studies