title: Factors affecting the outcome of extracorporeal shock wave lithotripsy for unilateral urinary stones in children: a 17-year single-institute experience.
abstract: OBJECTIVE
  Extracorporeal shock wave lithotripsy (ESWL) is a first-line treatment for pediatric urinary stone disease. We aimed to determine the factors affecting the outcome of ESWL for unilateral urinary stones in children.
  
  
  METHODS
  A total of 81 pediatric patients aged 0 to 16 years with urinary stones treated by ESWL from January 1995 through May 2012 were retrospectively reviewed. All patients were required to have unilateral urinary stone disease. Children who underwent other surgical procedures before ESWL were excluded. Outcomes evaluated after ESWL were the stone-free rate at 3 months after ESWL, success within a single session, and success within three sessions. Factors affecting the success within three sessions were also analyzed.
  
  
  RESULTS
  The final analysis was for 42 boys and 22 girls (mean age, 9.2±5.2 years). Of these 64 patients, 58 (90.6%) were treated by ESWL without other surgical procedures and 54 (84.4%) were successfully treated within three ESWL sessions. In the multivariate analysis, multiplicity (odds ratio [OR], 0.080; 95% confidence interval [CI], 0.012 to 0.534; p=0.009) and large stone size (>10 mm; OR, 0.112; 95% CI, 0.018 to 0.707; p=0.020) were significant factors that decreased the success rate within three ESWL sessions.
  
  
  CONCLUSIONS
  Most of the pediatric urinary stone patients in our study (90.6%) were successfully treated by ESWL alone without additional procedures. If a child has a large urinary stone (>10 mm) or multiplicity, clinicians should consider that several ESWL sessions might be needed for successful stone fragmentation.
authors.affiliation: Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: U-Seok
authors.initials: US
authors.lastname: Jeong
authors.forename: Sinwoo
authors.initials: S
authors.lastname: Lee
authors.forename: Junghun
authors.initials: J
authors.lastname: Kang
authors.forename: Deok Hyun
authors.initials: DH
authors.lastname: Han
authors.forename: Kwan Hyun
authors.initials: KH
authors.lastname: Park
authors.forename: Minki
authors.initials: M
authors.lastname: Baek
keywords: Lithotripsy; Pediatrics; Treatment outcome; Urinary calculi