title: Pediatric ureteroscopic management of intrarenal calculi.
abstract: OBJECTIVE
  Data addressing ureteroscopic management of intrarenal calculi in prepubertal children are limited. We reviewed our experience from January 2002 through December 2007.
  
  
  METHODS
  We retrospectively reviewed ureteroscopic procedures for intrarenal calculi in children younger than 14 years. Stone-free status was determined with postoperative imaging. Multiple logistic regression analysis was used to assess the influence of preoperative factors on initial stone-free status and the need for additional procedures.
  
  
  RESULTS
  Intrarenal calculi were managed ureteroscopically in 52 kidneys in 50 children with a mean age of 7.9 years (range 1.2 to 13.6). Mean stone size was 8 mm (range 1 to 16). Stone-free rate after a single ureteroscopic procedure was 50% (25 of 50 patients) on initial postoperative imaging and 58% (29 of 50) with extended followup. Initial stone-free status was dependent on preoperative stone size (p = 0.005) but not stone location. Additional stone procedures were required in 18 upper tracts. Younger patient age (p = 0.04) and larger preoperative stone size (p = 0.002) were associated with the need for additional procedures. Additional procedures were required in more than half of the stones 6 mm or larger but in no stone smaller than 6 mm.
  
  
  CONCLUSIONS
  Ureteroscopy is a safe method for the treatment of intrarenal calculi in the prepubertal population. Our ureteroscopic stone-free rate for intrarenal stones is lower than that reported for ureteral stones. Parents should be informed that additional procedures will likely be required, especially in younger patients and those with stones larger than 6 mm.
authors.affiliation: Division of Pediatric Urology, Monroe Carell Jr. Children's Hospital at Vanderbilt, Nashville, Tennessee 37232-9820, USA. stacy.tanaka@vanderbilt.edu
authors.forename: Stacy T
authors.initials: ST
authors.lastname: Tanaka
authors.forename: John H
authors.initials: JH
authors.lastname: Makari
authors.forename: John C
authors.initials: JC
authors.lastname: Pope
authors.forename: Mark C
authors.initials: MC
authors.lastname: Adams
authors.forename: John W
authors.initials: JW
authors.lastname: Brock
authors.forename: John C
authors.initials: JC
authors.lastname: Thomas
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007669:Kidney Calculi / Q000000981:diagnostic imaging* / Q000601:surgery*; D007902:Length of Stay; D008096:Lithotripsy / Q000379:methods; D016015:Logistic Models; D008297:Male; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D015999:Multivariate Analysis; D010372:Pediatrics; D011183:Postoperative Complications; D011336:Probability; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D020709:Ureteroscopes; D018666:Ureteroscopy / Q000379:methods*