To measure speech detection in noise performance for children with bilateral cochlear implants (BiCI), to compare performance in children with simultaneous implant versus those with sequential implant, and to compare performance to normal-hearing children.
Prospective cohort study.
Tertiary academic pediatric center.
Children with early-onset bilateral deafness and 2-year BiCI experience, comprising the "sequential" group (>2 yr interimplantation delay, n = 12) and "simultaneous group" (no interimplantation delay, n = 10) and normal-hearing controls (n = 8).
Thresholds to speech detection (at 0-degree azimuth) were measured with noise at 0-degree azimuth or ±90-degree azimuth.
Spatial unmasking (SU) as the noise condition changed from 0-degree azimuth to ±90-degree azimuth and binaural summation advantage (BSA) of 2 over 1 CI.
Speech detection in noise was significantly poorer than controls for both BiCI groups (p < 0.0001). However, the SU in the simultaneous group approached levels found in normal controls (7.2 ± 0.6 versus 8.6 ± 0.6 dB, p > 0.05) and was significantly better than that in the sequential group (3.9 ± 0.4 dB, p < 0.05). Spatial unmasking was unaffected by the side of noise presentation in the simultaneous group but, in the sequential group, was significantly better when noise was moved to the second rather than the first implanted ear (4.8 ± 0.5 versus 3.0 ± 0.4 dB, p < 0.05). This was consistent with a larger BSA from the sequential group's second rather than first CI.
Children with simultaneously implanted BiCI demonstrated an advantage over children with sequential implant by using spatial cues to improve speech detection in noise.
*Division of Pediatric Otolaryngology - Head and Neck Surgery, BC Children's Hospital, University of British Columbia, Vancouver; and †Cochlear Implant Research Laboratory and ‡Department of Otolaryngology - Head and Neck Surgery, The Hospital for Sick Children, University of Toronto, Toronto, Canada
Address correspondence and reprint requests to Neil K. Chadha, M.B.Ch.B.(Hons), F.R.C.S. (ORL-HNS), M.P.H., Division of Pediatric Otolaryngology - Head and Neck Surgery, BC Children's Hospital, 4480 Oak Street, Vancouver, Canada V6H 3V4; E-mail: firstname.lastname@example.org
This work was presented at the 12th International Symposium on Cochlear Implants in Children, held in Seattle, WA, June 17-20, 2009.
Dr. Papsin has acted as a consultant for Cochlear Corporation, a manufacturer of cochlear implants.