Single-sided deafness and cochlear implantation in congenital and acquired hearing loss in children

Abstract

Objective: To determine the audiological and clinical results of cochlear implantation in children below the age of 12 years old with congenital and acquired single-sided deafness.

Design: Observational, descriptive, transversal study.

Main outcome measures: Speech reception thresholds, Cortical responses, Auditory Lateralization Test and SSQ questionnaire.

Participants: Children < 12 implanted for congenital or acquired SSD.

Results: All the children with congenital SSD showed positive cortical responses. Positive results were obtained in the Auditory Lateralization Test for the following modalities: 0º, 45º and 90º. With respect to the Speech Test, the children with acquired SSD showed the following results: 92% and 100% in recognition and 48% and 68% (Azimuth modalities), Signal CI side 52% and 68% and Signal normal hearing side 44% - 60% (p < 0.05). In both group the processor was used for 6-12 hours. With respect to the SSQ questionnaire results, the parents were more satisfied within the post-operative period than within the pre-operative period (P<0.001).

Conclusions: Cochlear implant provides children with congenital SSD with significant audiological and subjective benefits. Children with congenital SSD and implanted after a longer period may not have an important benefit (binaural) although other bilateral effects can be achieved. Children with post-lingual unilateral deafness and after a short period of hearing deprivation probably integrated the normal acoustic hearing with the cochlear implant electrical signal and showed binaural benefits.