title: Comparing mechanical effects and sound production of KTP, thulium, and CO2 laser in stapedotomy.
abstract: OBJECTIVE
  The mechanical and acoustic effects that occur during laser-assisted stapedotomy differ among KTP, CO2, and thulium lasers.
  
  
  BACKGROUND
  Making a fenestration in stapedotomy with a laser minimizes the risk of a floating footplate caused by mechanical forces. Theoretically, the lasers used in stapedotomy could inflict mechanical trauma because of absorption in the perilymph, causing vaporization bubbles. These bubbles can generate a shock wave, when imploding.
  
  
  METHODS
  In an inner ear model, we made a fenestration in a fresh human stapes with KTP, CO2, and thulium laser. During the fenestration, we performed high-speed imaging from different angles to capture mechanical effects. The sounds produced by the fenestration were recorded simultaneously with a hydrophone; these recordings were compared with acoustics produced by a conventional microburr fenestration.
  
  
  RESULTS
  KTP laser fenestration showed little mechanical effects, with minimal sound production. With CO2 laser, miniscule bubbles arose in the vestibule; imploding of these bubbles corresponded to the acoustics. Thulium laser fenestration showed large bubbles in the vestibule, with a larger sound production than the other two lasers. Each type of laser generated significantly less noise than the microburr. The microburr maximally reached 95 ± 7 dB(A), compared with 49 ± 8 dB(A) for KTP, 68 ± 4 dB(A) for CO2, and 83 ± 6 dB(A) for thulium.
  
  
  CONCLUSIONS
  Mechanical and acoustic effects differ among lasers used for stapedotomy. Based on their relatively small effects, KTP and CO2 lasers are preferable to thulium laser.
authors: *Department of Otorhinolaryngology and Head & Neck Surgery, †Brain Center Rudolf Magnus, University Medical Center Utrecht; ‡Department of Physics and Medical Technology, VU University Medical Center Amsterdam; §Department of Medical Technology and Clinical Physics, University Medical Center Utrecht, The Netherlands; and ∥Jean Causse Ear Clinic, Transverse de Béziers, Colombiers, France.
authors: Digna M A
authors: DM
authors: Kamalski
authors: Rudolf M
authors: RM
authors: Verdaasdonk
authors: Tjeerd
authors: T
authors: de Boorder
authors: Robert
authors: R
authors: Vincent
authors: Huib
authors: H
authors: Versnel
authors: Wilko
authors: W
authors: Grolman
mesh_terms: D005276:Fenestration, Labyrinth / Q000379:methods*; D006801:Humans; D053685:Laser Therapy / Q000379:methods; D054020:Lasers, Gas; D053844:Lasers, Solid-State; D008953:Models, Anatomic; D009622:Noise; D010498:Perilymph; D013201:Stapes Surgery / Q000379:methods*; D013932:Thulium
chemical_list: D013932:Thulium