title: Speech recognition in bilaterally cochlear implanted adults in Tokyo, Japan.
abstract: BACKGROUND
  The clinical effects of bilateral cochlear implantation (BCI) include binaural summation and better hearing under noise conditions. This study retrospectively examined the utility of BCI compared to unilateral cochlear implantation (CI) in adults.
  
  
  METHODS
  We investigated 34 adults who underwent BCI, comparing speech recognition between BCI and first CI under silent and noise conditions. We assessed correlations between speech recognition after first and second CIs, and between the interval from first to second CI surgery and speech recognition of second CI.
  
  
  RESULTS
  Word recognition score (WRS) and sentence recognition score (SRS) were significantly better after BCI than after first CI under conditions of silence and noise. No significant correlation was found between speech recognition after first CI and that after second CI, or between inter-implant interval and speech recognition of second CI for either WRS or SRS.
  
  
  CONCLUSIONS
  The utility of BCI in Japanese patients was shown. Patients have no need to be pessimistic about hearing after the second implantation even if speech recognition after the first implantation is poor. A long interval from first CI does not necessarily contraindicate contralateral implantation in adults.
authors.affiliation: a Department of Otorhinolaryngology-Head and Neck Surgery , Tokyo Medical University , Tokyo , Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Ohta
authors.affiliation: a Department of Otorhinolaryngology-Head and Neck Surgery , Tokyo Medical University , Tokyo , Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kawano
authors.affiliation: a Department of Otorhinolaryngology-Head and Neck Surgery , Tokyo Medical University , Tokyo , Japan.
authors.forename: Sachie
authors.initials: S
authors.lastname: Kawaguchi
authors.affiliation: a Department of Otorhinolaryngology-Head and Neck Surgery , Tokyo Medical University , Tokyo , Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Shirai
authors.affiliation: a Department of Otorhinolaryngology-Head and Neck Surgery , Tokyo Medical University , Tokyo , Japan.
authors.forename: Kiyoaki
authors.initials: K
authors.lastname: Tsukahara
mesh_terms: D000328:Adult; D000368:Aged; D019929:Cochlear Implantation; D003054:Cochlear Implants; D003638:Deafness / Q000534:rehabilitation; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013063:Speech Discrimination Tests; D013067:Speech Perception
keywords: Bilateral; adult; cochlear implant; inter-implant interval; speech recognition