title: Vibro-EAS: a proposal for electroacoustic stimulation.
abstract: OBJECTIVE
  In situ evaluation of the vibration performance of a hybrid system for intracochlear fluid stimulation, constructed from a floating mass transducer (FMT) coupled to an electric acoustic stimulation (EAS) cochlea implant (CI) electrode.
  
  
  BACKGROUND
  EAS uses both CI technology to restore severe-to-profound hearing loss at high frequencies and acoustic amplification for mild-to-moderate hearing loss in the low-to-mid frequency range. More patients with residual hearing are becoming candidates for EAS surgery because of the improved techniques for hearing preservation. Most patients with partial deafness fulfill the audiological criteria at low and mid-frequencies for the active middle-ear implant with FMT (VSB). The FMT of the VSB is a potential device for acoustical stimulation in EAS.
  
  
  METHODS
  In seven fresh human temporal bones, stapes amplitude responses for fixation of a FMT to the long incus process (standard coupling) was compared with those for FMT fixation to a 20-mm inserted standard cochlea electrode array (31.5 mm) via the round window (Vibro-EAS). Vibration of the stapes footplate was measured by laser Doppler vibrometry.
  
  
  RESULTS
  For 0.316 Vrms drive voltage, stimulation of the intracochlear fluid using a FMT-driven CI electrode (Vibro-EAS) yielded stapes amplitude responses comparable to those for acoustic stimulation with 84 dB SPL. These amplitude responses are 30 to 42 dB lower at frequencies up to 4 kHz than those for VSB standard coupling.
  
  
  CONCLUSIONS
  Intracochlear combined electrical and mechanical stimulation may be a viable technique for electroacoustic stimulation. A reliable technique for attachment or integration of the FMT to the cochlea electrode array has yet to be developed.
authors.affiliation: *Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, Comprehensive Hearing Center, University of Würzburg, Würzburg, Germany, †Department of Oto-Rhino-Laryngology, Head and Neck Surgery, "Otto Koerner," Rostock University Medical Center, Rostock, Germany; ‡Department of Otolaryngology, Section of Physiological Acoustics and Communication, University of Tübingen, Tübingen, Germany; and §Department of Neuroradiology, University of Würzburg, Würzburg, Germany.
authors.forename: Sebastian P
authors.initials: SP
authors.lastname: Schraven
authors.forename: Robert
authors.initials: R
authors.lastname: Mlynski
authors.forename: Ernst
authors.initials: E
authors.lastname: Dalhoff
authors.forename: Daniela
authors.initials: D
authors.lastname: Wildenstein
authors.forename: Balint
authors.initials: B
authors.lastname: Alkonyi
authors.forename: Anthony W
authors.initials: AW
authors.lastname: Gummer
authors.forename: Rudolf
authors.initials: R
authors.lastname: Hagen
mesh_terms: D000161:Acoustic Stimulation / Q000295:instrumentation* / Q000379:methods*; D000368:Aged; D019929:Cochlear Implantation / Q000295:instrumentation / Q000379:methods; D003054:Cochlear Implants; D004599:Electric Stimulation Therapy / Q000295:instrumentation* / Q000379:methods*; D034381:Hearing Loss / Q000601:surgery; D006801:Humans; D008297:Male; D013701:Temporal Bone / Q000601:surgery