title: Considerations in minimally invasive surgery for renal and ureteric calculi: a bicenter quality control study.
abstract: BACKGROUND
  The use of minimally invasive surgery is increasing. Evaluating the quality of care brings new sights in the optimization of operating techniques.
  
  
  METHODS
  We included all procedures performed in two hospitals during 2010 and 2011. A total of 264 patients were included in the ureterorenoscopy (URS) group and 77 patients in the percutaneous nephrolitholapaxy (PCNL) group. Data were gathered by retrospectively reviewing medical records.
  
  
  RESULTS
  Mean stone diameter in the URS group was 9 mm. Patients suffered from a single stone in 79% of the cases. Calculi in the distal ureter, defined as the part of the ureter below the lower border of the sacroiliac joint, were most likely to be removed. A stone-free status was reached in 69% of the cases using URS. Mean stone diameter in the PCNL group was 23 mm. PCNL was successful in 70% of the cases in Haga Hospital versus 53% in Medisch Centrum Haaglanden. Incidence of complications was comparable between the hospitals (p = 0.5). Outcome and quality of both PCNL and URS was not influenced by sex, age or body mass index.
  
  
  CONCLUSIONS
  The clinical results were comparable with results in the literature. Further improvement can be made by optimization of technical aspects and centralization of treatment by urologists experienced in minimally invasive techniques.
authors.affiliation: Department of urology, Hagaziekenhuis, Leiden, Netherlands.
authors.forename: Saskia
authors.initials: S
authors.lastname: Weltings
authors.affiliation: Department of urology, Hagaziekenhuis, Leiden, Netherlands.
authors.forename: Hossain
authors.initials: H
authors.lastname: Roshani
authors.affiliation: Department of MC Haaglanden, The Hague, Leiden, Netherlands.
authors.forename: Joost
authors.initials: J
authors.lastname: Leenarts
authors.affiliation: Department of Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: Rob
authors.initials: R
authors.lastname: Pelger
keywords: Minimally invasive surgery; Percutaneous nephrolithotomy; Ureterorenoscopy; Urolithiasis