title: Comparing the efficacy and safety of 365- and 550-μm laser fibers in semirigid ureteroscopic Ho:YAG lithotripsy.
abstract: OBJECTIVE
  To compare the efficacy and safety of 365- and 550-μm Ho:YAG laser fiber in semirigid ureteroscopic lithotripsy and to identify parameters that may affect laser energy and time during the procedure.
  
  
  METHODS
  A database of 111 patients who undergone a semirigid ureteroscopy (SRURS) for ureteral stone lithotripsy was analyzed. A 365-μm core fiber was used in 56 cases, and a multiple-uses 550-μm laser fiber was used in 55 cases. A standard 6.4 W protocol (8 Hz, 0.8 J/pulse) was used in all cases. The association between laser fiber diameter and several preoperative, intraoperative and postoperative parameters was evaluated.
  
  
  RESULTS
  Mean stone burden was 54.1 ± 39.1 mm(2), and postoperative stone-free and complication rate was 100.0 and 16.2 %, respectively. The 550-μm laser fiber diameter was significantly associated with lower laser energy (p = 0.01), energy/mm(3) (p = 0.031), number of pulses (p = 0.012), laser time (p = 0.012) and laser time/mm(3) (p = 0.043), while it did not affect postoperative outcomes. The multivariate analysis showed that shorter procedure duration, smaller stone burden and the 550-μm laser fiber were all significant independent predictors for decreased laser energy consumption.
  
  
  CONCLUSIONS
  The 550-μm laser fiber may decrease laser energy and time during SRURS lithotripsy with Ho:YAG laser compared to the 365 μm. Given its lower cost, it may represent the optimal choice for semirigid procedures.
authors.affiliation: Department of Urology, Hadassah Hebrew University Medical Center, 5th Floor, Ein-Kerem, 91120, Jerusalem, Israel. sfoungaristosst@gmail.com.
authors.forename: Stavros
authors.initials: S
authors.lastname: Sfoungaristos
authors.affiliation: Department of Urology, Hadassah Hebrew University Medical Center, 5th Floor, Ein-Kerem, 91120, Jerusalem, Israel.
authors.forename: Ofer N
authors.initials: ON
authors.lastname: Gofrit
authors.affiliation: 1st Urology Department, Laiko Hospital, University of Athens, Athens, Greece.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Katafigiotis
authors.affiliation: Department of Urology, Hadassah Hebrew University Medical Center, 5th Floor, Ein-Kerem, 91120, Jerusalem, Israel.
authors.forename: Dov
authors.initials: D
authors.lastname: Pode
authors.affiliation: Department of Urology, Hadassah Hebrew University Medical Center, 5th Floor, Ein-Kerem, 91120, Jerusalem, Israel.
authors.forename: Ezekiel H
authors.initials: EH
authors.lastname: Landau
authors.affiliation: Department of Urology, Hadassah Hebrew University Medical Center, 5th Floor, Ein-Kerem, 91120, Jerusalem, Israel.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Yutkin
authors.affiliation: 1st Urology Department, Laiko Hospital, University of Athens, Athens, Greece.
authors.forename: Constantinos A
authors.initials: CA
authors.lastname: Constantinides
authors.affiliation: Department of Urology, Hadassah Hebrew University Medical Center, 5th Floor, Ein-Kerem, 91120, Jerusalem, Israel.
authors.forename: Mordechai
authors.initials: M
authors.lastname: Duvdevani
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D017602:Lithotripsy, Laser / Q000009:adverse effects / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D055100:Optical Fibers / Q000009:adverse effects; D012189:Retrospective Studies; D014514:Ureteral Calculi / Q000473:pathology / Q000628:therapy*; D020709:Ureteroscopes
keywords: Holmium; Laser; Lithotripsy; Ureteroscopy