title: Slow vs rapid delivery rate shock wave lithotripsy for pediatric renal urolithiasis: a prospective randomized study.
abstract: OBJECTIVE
  We compared slow vs fast shock wave frequency rates in disintegration of pediatric renal stones less than 20 mm.
  
  
  METHODS
  Our study included 60 children with solitary 10 to 20 mm radiopaque renal stones treated with shock wave lithotripsy. Patients were prospectively randomized into 2 groups, ie those undergoing lithotripsy at a rate of 80 shock waves per minute (group 1, 30 patients) and those undergoing lithotripsy at a rate of 120 shock waves per minute (group 2, 30 patients). The 2 groups were compared in terms of treatment success, anesthesia time, secondary procedures and efficiency quotient.
  
  
  RESULTS
  Stone clearance rate was significantly higher in group 1 (90%) than in group 2 (73.3%, p = 0.025). A total of 18 patients in group 1 (60%) were rendered stone-free after 1 session, 8 required 2 sessions and 1 needed 3 sessions, while shock wave lithotripsy failed in 3 patients. By comparison, 8 patients (26.6%) in group 2 were rendered stone-free after 1 session, 10 (33.3%) required 2 sessions and 4 (13.3%) needed 3 sessions to become stone-free. Mean general anesthesia time was significantly longer in group 1 (p = 0.041). Postoperatively 2 patients in group 1 and 4 in group 2 suffered low grade fever (Clavien grade II). Significantly more secondary procedures (percutaneous nephrolithotomy, repeat shock wave lithotripsy) were required in group 2 (p = 0.005). The predominant stone analysis was calcium oxalate dihydrate in both groups. Efficiency quotient was 0.5869 and 0.3437 for group 1 and group 2, respectively (p = 0.0247).
  
  
  CONCLUSIONS
  In children with renal stones slow delivery rates of shock wave lithotripsy have better results regarding stone clearance than fast delivery rates.
authors.affiliation: Urology Department, Faculty of Medicine, Cairo University, Giza, Egypt. Electronic address: dr_hosni@yahoo.com.
authors.forename: Hosni Khairy
authors.initials: HK
authors.lastname: Salem
authors.affiliation: Urology Department, Faculty of Medicine, Cairo University, Giza, Egypt.
authors.forename: Hesham
authors.initials: H
authors.lastname: Fathy
authors.affiliation: Urology Department, Faculty of Medicine, Cairo University, Giza, Egypt.
authors.forename: Hanny
authors.initials: H
authors.lastname: Elfayoumy
authors.affiliation: Urology Department, Faculty of Medicine, Cairo University, Giza, Egypt.
authors.forename: Hussein
authors.initials: H
authors.lastname: Aly
authors.affiliation: Urology Department, Faculty of Medicine, Cairo University, Giza, Egypt.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Ghonium
authors.affiliation: Urology Department, Faculty of Medicine, Cairo University, Giza, Egypt.
authors.forename: Mostafa A
authors.initials: MA
authors.lastname: Mohsen
authors.affiliation: Urology Department, Faculty of Medicine, Cairo University, Giza, Egypt.
authors.forename: Abd El Rahim
authors.initials: Ael R
authors.lastname: Hegazy
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000628:therapy*; D008096:Lithotripsy / Q000379:methods*; D008297:Male; D011446:Prospective Studies; D013997:Time Factors
keywords: high-energy shock waves; kidney calculi; lithotripsy; pediatrics; urolithiasis