title: Micro-ureteroscopy for the treatment of distal ureteral calculi in children.
abstract: OBJECTIVE
  The objective of this study was to demonstrate the efficacy and safety of micro-ureteroscopy (micro-URS) in the management of distal ureteral stones in the pediatric population.
  
  
  METHODS
  A total of 11 children, who had undergone micro-URS between September 2015 and April 2016 with the indication of distal ureteral calculi in two referral centers, were retrospectively evaluated. The procedures were performed with the patient in the lithotomy position under general anesthesia using the standard URS technique with a micro-ureteroscope that has a caliber of 4.85 Fr all along its length. Demographics, perioperative data, and outcomes were assessed.
  
  
  RESULTS
  Right (n=6) and left (n=8) ureteral stones were detected in the respective number of patients. The mean age of the children was calculated as 55.1months (range, 6-161months). The median stone size was 10.5mm (range, 6-24mm). The median operative time was 36.8min (range, 23-68min). A double 3 stent was implanted in 3 of 11 patients because of severe edema. As a postoperative complication mild hematuria (Clavien grade 1) was observed in one case and resolved spontaneously. Intraoperative minor or major complication did not occur in any of the cases. The mean hospitalization time was determined as 21.4h (range, 10-28h). Stone-free status was accomplished in all patients in the final assessment.
  
  
  CONCLUSIONS
  The outcomes of our series show that micro-URS can be used safely and effectively in the treatment of pediatric distal ureteral stones. Further prospective and comparative studies comparing instruments of different size are warranted.
authors.affiliation: Department of Urology, Faculty of Medicine, Dicle University, Diyarbakir, Turkey. Electronic address: drmazhar21@hotmail.com.
authors.forename: Mehmet Mazhar
authors.initials: MM
authors.lastname: Utanğaç
authors.affiliation: Department of Urology, Faculty of Medicine, Dicle University, Diyarbakir, Turkey.
authors.forename: Ahmet Ali
authors.initials: AA
authors.lastname: Sancaktutar
authors.affiliation: Department of Urology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkey.
authors.forename: Abdulkadir
authors.initials: A
authors.lastname: Tepeler
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007902:Length of Stay; D008096:Lithotripsy / Q000379:methods; D008297:Male; D012189:Retrospective Studies; D016896:Treatment Outcome; D014514:Ureteral Calculi / Q000473:pathology / Q000601:surgery*; D020709:Ureteroscopes; D018666:Ureteroscopy / Q000379:methods*
keywords: Children; Distal ureteral calculi; Efficacy; Miniaturization; Safety; Ureteroscopy