title: Bilateral cochlear implantation in children: localization and hearing in noise benefits.
abstract: OBJECTIVE
  The aim of this study was to report speech performance in quiet and in noise, sound localization with cochlear implanted children bilaterally. Their performances were compared also in unilateral conditions. In addition, speech and language evaluation was analyzed.
  
  
  METHODS
  Twenty-three children implanted with Neurelec Digisonic SP devices in 3 tertiary centres were tested on a battery of speech perception tests in quiet and in noise. Localization was assessed by lateralization tasks (90° and 30°). Progress in speech and language development and subjective assessment of benefit were assessed using several rating scales and questionnaires (categories of auditory perception, speech intelligibility rating, family participating rating scale).
  
  
  RESULTS
  Children scored better when tested in bilateral conditions rather than in unilateral conditions. In quiet, the mean scores for the poorer and better side were 52% and 73%, respectively. In the bilateral condition, the mean score increased to 83%. In noise, the mean scores were 39% and 57% respectively, which increased to a mean of 70% in the bilateral condition. Nine children (<9 years) completed the ±90° lateralization task. For both unilateral conditions performance was not significantly different from chance level. In the bilateral condition, the mean score was 86%. The ±30° lateralization score was completed by eight of the older children (>9 years). The scores in the unilateral conditions were closed to chance level, but significantly better in the bilateral condition (mean of 86%).
  
  
  CONCLUSIONS
  Performances in bilateral conditions were significantly better than in unilateral conditions on speech perception in quiet and in noise. Localization was significantly better when tested in the bilateral condition for ±90° lateralization task for the younger children and the ±30° task for the older children. All these results supported the hypothesis than bilateral cochlear implantation is more beneficial than unilateral implantation in children.
authors.affiliation: Service Otologie et Otoneurologie, Centre Hospitalier Régional Universitaire de Lille, rue E. Laine, Lille Cedex, France. christophe.vincent@chru-lille.fr
authors.forename: Christophe
authors.initials: C
authors.lastname: Vincent
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Bébéar
authors.forename: Emilien
authors.initials: E
authors.lastname: Radafy
authors.forename: François-Michel
authors.initials: FM
authors.lastname: Vaneecloo
authors.forename: Isabelle
authors.initials: I
authors.lastname: Ruzza
authors.forename: Sylvie
authors.initials: S
authors.lastname: Lautissier
authors.forename: Philippe
authors.initials: P
authors.lastname: Bordure
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D019929:Cochlear Implantation; D003054:Cochlear Implants; D003638:Deafness / Q000175:diagnosis / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D005602:France; D006312:Hearing Loss, Bilateral / Q000175:diagnosis / Q000601:surgery*; D006320:Hearing Tests / Q000379:methods; D006801:Humans; D007804:Language Development; D008297:Male; D009622:Noise; D011474:Prosthesis Design; D018570:Risk Assessment; D013017:Sound Localization; D013067:Speech Perception / Q000502:physiology*; D013068:Speech Production Measurement; D013069:Speech Reception Threshold Test; D013997:Time Factors; D016896:Treatment Outcome