title: Comparison of the Nanopulse Lithotripter to the Holmium Laser: Stone Fragmentation Efficiency and Impact on Flexible Ureteroscope Deflection and Flow.
abstract: The Nanopulse Lithotripter (NPL; Lithotech Medical, Israel) is a novel intracorporeal device that uses a nanosecond duration electrical discharge through a reusable flexible coaxial probe to endoscopically fragment urinary stones. This device was compared with a holmium laser lithotripsy (HoL) with regard to stone fragmentation efficiency (SFE) and its impact on flexible ureteroscope (URS) deflection and flow of irrigation.
  
  
  
  Using a custom bench model, a 6 mm BegoStone cylindrical phantom (mixture 5:2) was confined under 0.9% saline atop sequential mesh sieves. The SFE of two NPL probe sizes (2.0F, 3.6F) and two HoL fibers (200, 365 μm) was evaluated using concordant settings of 1 J and 5 Hz. URS deflection and irrigation flow with NPL probes in the working channel were tested in five new fourth generation flexible URS and compared with other adjunct endourologic instruments.
  
  
  
  The 2.0F NPL showed improved SFE compared with the 200 μm laser (86 mg/min vs 52 mg/min, p = 0.014) as did the 3.6F NPL vs the 365 μm laser (173 mg/min vs 80 mg/min, p = 0.05). The NPL created more 1 to 2 mm fragments; the laser created more dust. URS deflection reduced by 3.75° with the 2.0 NPL probe. URS irrigation flow reduced from 36.5 to 6.3 mL/min with the 2.0F NPL probe.
  
  
  
  NPL shows improved SFE compared with HoL. Flow with the 2.0F probe is akin to a stone basket. NPL offers an effective alternative to HoL.
authors.affiliation: 1 Division of Urologic Surgery, Duke University Medical Center , Durham, North Carolina.
authors.forename: Adam G
authors.initials: AG
authors.lastname: Kaplan
authors.affiliation: 1 Division of Urologic Surgery, Duke University Medical Center , Durham, North Carolina.
authors.forename: Tony T
authors.initials: TT
authors.lastname: Chen
authors.affiliation: 2 Mechanical Engineering and Materials Science, Duke University , Durham, North Carolina.
authors.forename: Georgy
authors.initials: G
authors.lastname: Sankin
authors.affiliation: 2 Mechanical Engineering and Materials Science, Duke University , Durham, North Carolina.
authors.forename: Chen
authors.initials: C
authors.lastname: Yang
authors.affiliation: 1 Division of Urologic Surgery, Duke University Medical Center , Durham, North Carolina.
authors.forename: Joanne A
authors.initials: JA
authors.lastname: Dale
authors.affiliation: 2 Mechanical Engineering and Materials Science, Duke University , Durham, North Carolina.
authors.forename: W Neal
authors.initials: WN
authors.lastname: Simmons
authors.affiliation: 2 Mechanical Engineering and Materials Science, Duke University , Durham, North Carolina.
authors.forename: Pei
authors.initials: P
authors.lastname: Zhong
authors.affiliation: 1 Division of Urologic Surgery, Duke University Medical Center , Durham, North Carolina.
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Preminger
authors.affiliation: 1 Division of Urologic Surgery, Duke University Medical Center , Durham, North Carolina.
authors.forename: Michael Eric
authors.initials: ME
authors.lastname: Lipkin
mesh_terms: D004724:Endoscopy / Q000379:methods; D004867:Equipment Design; D006695:Holmium; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D017602:Lithotripsy, Laser / Q000295:instrumentation* / Q000379:methods; D019047:Phantoms, Imaging; D020709:Ureteroscopes; D018666:Ureteroscopy / Q000379:methods; D014545:Urinary Calculi / Q000628:therapy*; D052878:Urolithiasis / Q000628:therapy
chemical_list: D006695:Holmium
keywords: holmium laser; instrumentation; lithotripsy; nanoelectric pulse; nanopulse; ureteroscopy