title: A Novel Ureterorenoscope for the Management of Upper Urinary Tract Stones: Initial Experience from a Prospective Multicenter Study.
abstract: OBJECTIVE
  This prospective single-arm multicenter clinical trial was conducted to evaluate the safety and efficacy of the Sun's tip-flexible semirigid ureterorenoscope (tf-URS) when used for managing upper urinary tract stones.
  
  
  METHODS
  Data from patients who underwent ureteroscopy using the tf-URS for proximal and renal stone removal were prospectively collected from seven Chinese clinical centers. The primary study end point was the stone clearance at the 2-week follow-up. Other data associated with the procedure were also collected.
  
  
  RESULTS
  Between October and December of 2014, this study enrolled a total of 254 patients; among which, 235 patients were eligible for ureteroscopy, 216 of whom were treated using the tf-URS. Among all treated patients, 135 had proximal ureteral stones (group 1) while 81 had renal stones (group 2). The overall success rate of endoscope advancement was 91.9% (216/235). The mean fragmentation times were 17.5±12.6 minutes and 23.3±15.1 minutes for groups 1 and 2, respectively, and corresponded to an experience-dependent increase in fragmentation speed in both groups. The mean operative times were 31.9±15.5 minutes and 39.5±2 0.3 minutes for groups 1 and 2, respectively. The access rate to renal stones in group 2 was 96% (76/81). All treated patients were assessed during a 2-week follow-up period. The stone-free rates at the 2-week follow-up for groups 1 and 2 were 98.7% (133/135) and 91.3% (74/81), respectively. Adverse events were observed in 7.3% (16/216) of the patients; however, all were classified as Grade I or Grade II complications.
  
  
  CONCLUSIONS
  Based on our initial experience in the current study, the tf-URS can be safely and effectively used to manage proximal ureteral and renal stones with a low rate of complications. Future studies are needed to focus on a transverse comparison between the tf-URS and conventional ureteroscopes.
authors: 1 Department of Urology, Changhai Hospital, Second Military Medical University , Shanghai, China .
authors: Xiaofeng
authors: X
authors: Gao
authors: 2 Department of Urology, the First Affiliated Hospital of Guangzhou Medical University , Guangzhou, China .
authors: Guohua
authors: G
authors: Zeng
authors: 3 Department of Urology, Xiangya Hospital, Central South University , Changsha, China .
authors: Hequn
authors: H
authors: Chen
authors: 4 Department of Urology, Ningbo First Hospital, Ningbo University , Ningbo, China .
authors: Yue
authors: Y
authors: Cheng
authors: 5 Department of Urology, West China Hospital, Sichuan University , Chengdu, China .
authors: Kunjie
authors: K
authors: Wang
authors: 6 Department of Urology, Tsinghua Changgung Hospital Beijing, China .
authors: JianXing
authors: J
authors: Li
authors: 7 Department of Urology, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College, Qingdao University , Yantai, China .
authors: Lei
authors: L
authors: Shi
authors: 1 Department of Urology, Changhai Hospital, Second Military Medical University , Shanghai, China .
authors: Ling
authors: L
authors: Li
authors: 1 Department of Urology, Changhai Hospital, Second Military Medical University , Shanghai, China .
authors: Yonghan
authors: Y
authors: Peng
authors: Min
authors: M
authors: Liu
authors: 1 Department of Urology, Changhai Hospital, Second Military Medical University , Shanghai, China .
authors: Qiheng
authors: Q
authors: Wang
authors: 1 Department of Urology, Changhai Hospital, Second Military Medical University , Shanghai, China .
authors: Chuanliang
authors: C
authors: Xu
authors: 1 Department of Urology, Changhai Hospital, Second Military Medical University , Shanghai, China .
authors: Yinghao
authors: Y
authors: Sun
mesh_terms: D002681:China; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D011183:Postoperative Complications; D011446:Prospective Studies; D012449:Safety; D016896:Treatment Outcome; D014514:Ureteral Calculi / Q000601:surgery*; D020709:Ureteroscopes; D018666:Ureteroscopy / Q000295:instrumentation* / Q000379:methods