title: Hearing preservation via a cochleostomy approach and deep insertion of a standard length cochlear implant electrode.
abstract: OBJECTIVE
  The suggestion that the depth of insertion of the electrode into the cochlea is critical to hearing preservation has led to the development of a generation of short electrodes designed to minimize intracochlear trauma and avoid contact with the apical region of the cochlea. This study aims to describe our experience of hearing preservation surgery using a deeply inserted standard length electrode array covering the region of residual hearing.
  
  
  METHODS
  A retrospective case note review was performed identifying cases of attempted hearing preservation using standard length electrodes.
  
  
  METHODS
  Study based at Manchester Royal Infirmary, a tertiary referral center.
  
  
  METHODS
  Fourteen cochlear implants in 13 patients were identified for further analysis from the Manchester Cochlear Implant Programme database.
  
  
  METHODS
  Each patient received the same design of implant using a "soft" surgical technique.
  
  
  METHODS
  Preoperative and postoperative air conduction thresholds were compared to assess the degree of hearing preservation.
  
  
  RESULTS
  Successful hearing preservation was demonstrated in 12 of 14 cases, and the postoperative residual hearing thresholds in 3 adolescents receiving a standard length electrode array were found to have improved. Preservation of speech recognition was not measured in this study, rather hearing was tested by pure tone audiogram. Follow-up at the time of this study ranged from 1 week to 23 months.
  
  
  CONCLUSIONS
  This study demonstrates that deep insertion of the electrode into the cochlea does not preclude successful hearing preservation. It also highlights that residual hearing can be consistently preserved using a "cochleostomy" approach.
authors.affiliation: Manchester Auditory Implant Centre, Manchester, UK.
authors.forename: Iain Alexander
authors.initials: IA
authors.lastname: Bruce
authors.forename: James Edward Homewood Mills
authors.initials: JE
authors.lastname: Bates
authors.forename: Christine
authors.initials: C
authors.lastname: Melling
authors.forename: Deborah
authors.initials: D
authors.lastname: Mawman
authors.forename: Kevin Michael John
authors.initials: KM
authors.lastname: Green
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology*; D002648:Child; D019929:Cochlear Implantation; D003054:Cochlear Implants; D005260:Female; D006309:Hearing / Q000502:physiology*; D006319:Hearing Loss, Sensorineural / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013067:Speech Perception / Q000502:physiology*