title: Intraoperative auditory steady state response measurements during Vibrant Soundbridge middle ear implantation in patients with mixed hearing loss: preliminary results.
abstract: OBJECTIVE
  To optimize intraoperatively the coupling of the floating mass transducer (FMT) of the Vibrant Soundbridge middle ear implant to the round or oval cochlear window in patients with mixed hearing loss.
  
  
  METHODS
  Intraoperative measurement of objective hearing thresholds using auditory steady state responses (ASSRs).
  
  
  METHODS
  Radboud University Nijmegen Medical Centre, tertiary referral hospital.
  
  
  METHODS
  Four individuals with mixed hearing loss and, at least no incus, in need for a middle ear implant.
  
  
  METHODS
  Surgical placement of the Vibrant Soundbridge. ASSR thresholds were measured intraoperatively, whereas FMT coupling to the cochlea was manipulated to find the most effective coupling of the FMT.
  
  
  METHODS
  Differences in ASSR thresholds between different FMT coupling options within patients.
  
  
  RESULTS
  With ASSR, we assessed placement of the FMT in the round window niche, loosely or tightly packed in the niche; creation of a mobile window in case of a fixed stapes footplate; and FMT position coupled to the stapes that afforded vibration in the natural vibration direction or perpendicular to it. Furthermore, test-retest variations in ASSR thresholds were studied. It was shown that differences in ASSR thresholds could be detected, while manipulating the FMT couplings, which were statistically significant.
  
  
  CONCLUSIONS
  Intraoperative ASSR measurement is a good method to study different positions of the FMT and to determine the best position of the FMT for a patient.
authors: Department of Otorhinolaryngology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. v.verhaegen@kno.umcn.nl
authors: Veronique J O
authors: VJ
authors: Verhaegen
authors: Jef J S
authors: JJ
authors: Mulder
authors: John F P
authors: JF
authors: Noten
authors: Bart M A
authors: BM
authors: Luijten
authors: Cor W R J
authors: CW
authors: Cremers
authors: Ad F M
authors: AF
authors: Snik
mesh_terms: D000368:Aged; D001309:Auditory Threshold / Q000502:physiology; D004432:Ear, Middle / Q000502:physiology*; D004569:Electroencephalography; D005240:Feasibility Studies; D005260:Female; D046089:Hearing Loss, Mixed Conductive-Sensorineural / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D009998:Ossicular Prosthesis; D019919:Prosthesis Implantation / Q000379:methods*; D015203:Reproducibility of Results; D012405:Round Window, Ear / Q000502:physiology / Q000601:surgery; D013201:Stapes Surgery