title: A multicenter comparison of the safety and effectiveness of ureteroscopic laser lithotripsy in obese and normal weight patients.
abstract: OBJECTIVE
  Surgical treatment of kidney stones in an obese patient (body mass index [BMI] >30 kg/m(2)) remains challenging as shockwave lithotripsy may not be an option due to weight limitations. We sought to determine the effectiveness of ureteroscopic laser lithotripsy in obese patients compared to nonobese controls.
  
  
  METHODS
  Patients from 2004 to 2007 were retrospectively analyzed providing a group of 292 patients (163 obese, 76 overweight, 53 normal) who underwent ureteroscopic procedures for urolithiasis at four centers in the United States and Canada.
  
  
  RESULTS
  The percentage of obese patients requiring flexible ureteroscopy (URS) (79%) was higher than in the other groups (P<0.0001). Flexible URS was associated with a lower stone-free rate (SFR) on multivariate analysis (P=0.034). There was no difference in SFRs of patients who required a ureteral access sheath, basket extraction, or received a postoperative stent. Complication rates did not differ between groups.
  
  
  CONCLUSIONS
  SFRs using ureteroscopic lithotripsy in obese and overweight populations are the same as in the normal weight patients. A flexible ureteroscope was associated with a decreased SFR, but this likely due to a more proximal stone location in these patients. Ureteroscopic laser lithotripsy is an effective and safe technique to treat urolithiasis in the overweight/obese patient.
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, Canada. ben.chew@ubc.ca
authors.forename: Ben H
authors.initials: BH
authors.lastname: Chew
authors.forename: Bogard
authors.initials: B
authors.lastname: Zavaglia
authors.forename: Ryan F
authors.initials: RF
authors.lastname: Paterson
authors.forename: Joel M H
authors.initials: JM
authors.lastname: Teichman
authors.forename: Dirk
authors.initials: D
authors.lastname: Lange
authors.forename: Christopher
authors.initials: C
authors.lastname: Zappavigna
authors.forename: Brian R
authors.initials: BR
authors.lastname: Matlaga
authors.forename: Rafael
authors.initials: R
authors.lastname: Nunez-Nateras
authors.forename: Aron
authors.initials: A
authors.lastname: Bruhn
authors.forename: Hernan O
authors.initials: HO
authors.lastname: Altamar
authors.forename: Mitchell R
authors.initials: MR
authors.lastname: Humphreys
authors.forename: Ojas
authors.initials: O
authors.lastname: Shah
authors.forename: Nicole L
authors.initials: NL
authors.lastname: Miller
mesh_terms: D001835:Body Weight; D006801:Humans; D007669:Kidney Calculi / Q000150:complications* / Q000601:surgery*; D017602:Lithotripsy, Laser / Q000009:adverse effects* / Q000379:methods*; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D050177:Overweight / Q000150:complications; D012189:Retrospective Studies; D014514:Ureteral Calculi / Q000150:complications* / Q000601:surgery*; D018666:Ureteroscopy