title: Shock wave lithotripsy for uric acid stones.
abstract: OBJECTIVE
  To report our experience of extracorporeal shock wave lithotripsy (SWL) for patients with uric acid stones.
  
  
  METHODS
  From December 1987 to December 2003, a total of 443 patients with uric acid stones in the kidney or ureter accepted SWL using ultrasound-guided lithotripters together with alkali therapy. Among them, 168 patients with an average stone burden of 9.1 mm were treated using an EDAP LT-01 piezoelectric lithotripter. The other patients, with an average stone burden of 9.6 mm, were treated using a Dornier Compact S electromagnetic lithotripter.
  
  
  RESULTS
  The average duration of treatment using the EDAP LT-01 device was 52.1 minutes with a pulse frequency of 1.25-2.5 shocks per second at 100% power. The average treatment parameters on the Dornier Compact S device were 3,196 shocks at 14.8 kV. For the EDAP LT-01, the 3-month stone-free rate was 86.4%, with a retreatment rate of 24.2%. For the Dornier Compact S, the 3-month stone-free rate was 90.3%, with a retreatment rate of 29.0%. Auxiliary therapy with the push-back technique was needed in 0.45% of patients with upper ureteral stones that could not be localized using ultrasound. The treatment results were best for stones smaller than 20 mm. No anaesthesia was required for any patient.
  
  
  CONCLUSIONS
  SWL with ultrasound localization for uric acid stones is safe and effective. The combination of SWL with urine alkalization may further improve the stone-free rate.
authors.affiliation: Department of Urology, Affiliated Drum Tower Hospital, Nanjing University, Zhongshan Road 321, Nanjing, Jiangsu Province, China. sunxizhao@sohu.com
authors.forename: Xi-Zhao
authors.initials: XZ
authors.lastname: Sun
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000628:therapy*; D008096:Lithotripsy; D008297:Male; D008875:Middle Aged; D014514:Ureteral Calculi / Q000628:therapy*; D014527:Uric Acid
chemical_list: D014527:Uric Acid