title: Same-session bilateral retrograde intrarenal surgery for upper urinary system stones: safety and efficacy.
abstract: OBJECTIVE
  We present our experience with same-session retrograde intrarenal surgery (RIRS) for the management of bilateral upper urinary system stones (UUSS) in terms of clearance of stones, operative times, duration of hospital stay, and complications.
  
  
  METHODS
  Between November 2007 and January 2013, a total of 44 simultaneous bilateral RIRS were performed at our hospital. Initially, symptomatic sides of the patients were operated on, and, when asymptomatic, the greater stone burden was treated first. Having completed stone fragmentation with a holmium:YAG laser, larger fragments were extracted with a nitinol basket. All patients underwent noncontrast CT scanning or urinary ultrasonography 2 months after the removal of the stent to detect any residual fragments. The stone-free status was defined as no fragments and/or the presence of asymptomatic fragments <4 mm in the urinary system.
  
  
  RESULTS
  The total stone number was 201 with a mean stone burden per patient of 30.0±15.4 mm (range 10-85 mm). The overall stone-free rate (SFR) was 88.6% after all procedures. The patients in this study were divided into two groups according to stone burden: Although the overall SFR was 100% for a stone burden <25 mm, the SFR was 80% for a stone burden ≥25 mm (P=0.006). A Double-J stent was not placed in two patients, and they developed postoperative anuria; both cases were treated with Double-J stent placement.
  
  
  CONCLUSIONS
  Bilateral same-session RIRS is a safe and effective procedure that can be considered a first-line treatment for bilateral UUSS in select patients. The SFR is satisfactory, especially in patients with a stone burden <25 mm. At minimum a unilateral Double-J stent should be placed in patients undergoing bilateral RIRS to avoid postrenal failure.
authors.affiliation: 1 Department of Urology, Memorial Istanbul Sisli Hospital , Istanbul, Turkey .
authors.forename: Erdal
authors.initials: E
authors.lastname: Alkan
authors.forename: Egemen
authors.initials: E
authors.lastname: Avci
authors.forename: Ahmet Oguz
authors.initials: AO
authors.lastname: Ozkanli
authors.forename: Oguz
authors.initials: O
authors.lastname: Acar
authors.forename: Mevlana Derya
authors.initials: MD
authors.lastname: Balbay
mesh_terms: D000328:Adult; D001002:Anuria / Q000628:therapy; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D053844:Lasers, Solid-State / Q000627:therapeutic use; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D015607:Stents; D055815:Young Adult