A novel difficulty scoring system for laparoscopic liver resection

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…