title: Comparison of percutaneous nephrolithotomy and retrograde flexible nephrolithotripsy for the management of 2-4 cm stones: a matched-pair analysis.
abstract: Study Type--Therapy (case control). Level of Evidence 3b. What's known on the subject? and What does the study add? Recently European Association of Urology 2011 guidelines on urolithiasis recommended retrograde intrarenal surgery as the second-line therapy for the treatment of kidney stones <10 mm in diameter. This study shows that retrograde intrarenal surgery may be an alternative therapy to percutaneous nephrolithotomy, with acceptable efficacy and low morbidity for 2-4 cm stones.
  
  
  OBJECTIVE
  • Currently, the indications for retrograde intrarenal surgery (RIRS) have been extended due to recent improvements in endoscopic technology. In this study, we compare the outcomes of percutaneous nephrolithotomy (PCNL) and RIRS in the treatment of 2-4 cm kidney stones.
  
  
  METHODS
  • Between September 2008 and January 2011, 34 patients who had renal stones ranging from 2 to 4 cm in diameter were treated with RIRS. The outcomes of these patients were compared with patients who underwent PCNL using matched-pair analysis (1:1 scenario). • The matching parameters were the size, number and location of the stones as well as age, gender, body mass index, solitary kidney, degree of hydronephrosis, presence of previous shock wave lithotripsy and open surgery. • Data were analysed using Fisher's exact test, Student's t test and the Mann-Whitney U test.
  
  
  RESULTS
  • Stone-free rates after one session were 73.5% and 91.2% for RIRS and PCNL respectively (P= 0.05). Stone-free rate in the RIRS group improved to 88.2% after the second procedure. • Mean operation duration was 58.2 (±) 13.4 min in the RIRS group but 38.7 (±) 11.6 min in the PCNL group (P < 0.0001). Blood transfusions were required in two patients in the PCNL group. • Overall complication rates in the PCNL group were higher, but the differences were not statistically significant. Hospitalization time was significantly shorter in the RIRS group (30.0 + 37.4 vs 61.4 + 34.0 h, respectively; P < 0.001).
  
  
  CONCLUSIONS
  • Satisfactory outcomes can be achieved with multi-session RIRS in the treatment of 2-4 cm renal stones. RIRS can be used as an alternative treatment to PCNL in selected cases with larger renal stones.
authors.affiliation: Department of Urology, Haseki Training and Research Hospital, Istanbul, Turkey. takman36@gmail.com
authors.forename: Tolga
authors.initials: T
authors.lastname: Akman
authors.forename: Murat
authors.initials: M
authors.lastname: Binbay
authors.forename: Faruk
authors.initials: F
authors.lastname: Ozgor
authors.forename: Mesut
authors.initials: M
authors.lastname: Ugurlu
authors.forename: Erdem
authors.initials: E
authors.lastname: Tekinarslan
authors.forename: Cem
authors.initials: C
authors.lastname: Kezer
authors.forename: Rahmi
authors.initials: R
authors.lastname: Aslan
authors.forename: Ahmet Yaser
authors.initials: AY
authors.lastname: Muslumanoglu
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000601:surgery*; D008096:Lithotripsy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome; D018666:Ureteroscopy