title: Preliminary experience and learning curve for laparoendoscopic single-site retroperitoneal pyeloplasty.
abstract: OBJECTIVE
  To report our preliminary experience and to assess the learning curve for laparoendoscopic single-site retroperitoneal pyeloplasty (LESS-RP) for ureteropelvic junction obstruction (UPJO).
  
  
  METHODS
  From July 2010 to February 2012, LESS-RP was performed in 27 patients affected with UPJO by a single surgeon. A homemade single-access platform and both conventional and prebent instruments were applied. Patient characteristics and perioperative outcomes were analyzed. The cumulative sum (CUSUM) method was used to evaluate the learning curve.
  
  
  RESULTS
  The LESS-RP was successfully accomplished in all 27 patients. The mean operative time (OT) was 175.9±22.5 minutes, and the mean estimated blood loss was 83.3±27.1 mL. We used the OT as a proxy to assess the learning curve. The CUSUM learning curve can be divided into two distinct phases: the initial 12 cases and the last 15 cases. There were significant differences in the mean OT (195.6 minutes versus 159.1 minutes, P<.001) and mean estimated blood loss (97.2 mL versus 72.2 mL, P=.014) between the two phases. The two phases did not differ in other parameters.
  
  
  CONCLUSIONS
  LESS-RP is a safe and feasible procedure. The learning curve of a single surgeon suggests that the initial learning phase for LESS-RP can be completed after approximately 12 cases.
authors.affiliation: Department of Urology, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Ou
authors.forename: Lin
authors.initials: L
authors.lastname: Qi
authors.forename: Jinrui
authors.initials: J
authors.lastname: Yang
authors.forename: Xiang
authors.initials: X
authors.lastname: Chen
authors.forename: Zhenzhen
authors.initials: Z
authors.lastname: Cao
authors.forename: Xiongbing
authors.initials: X
authors.lastname: Zu
authors.forename: Longfei
authors.initials: L
authors.lastname: Liu
authors.forename: Long
authors.initials: L
authors.lastname: Wang
mesh_terms: D000328:Adult; D016063:Blood Loss, Surgical; D002983:Clinical Competence; D005260:Female; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D059032:Learning Curve; D008297:Male; D061646:Operative Time; D010147:Pain Measurement; D011183:Postoperative Complications; D012187:Retroperitoneal Space / Q000601:surgery*; D016896:Treatment Outcome; D014517:Ureteral Obstruction / Q000601:surgery*