Cochlear Implantation in Children With Congenital Single-Sided Deafness

Objective: To determine audiological and clinical results of cochlear implantation in children with congenital single sided deafness (SSD), with an emphasis on children implanted before and after 6 years of age. Study Design: Retrospective study. Setting: Tertiary referral center. Subjects: Twenty one children with congenital SSD who were implanted aged 10 months to 11; 3 years. Intervention: Unilateral cochlear implantation. Main Outcome Measures: Speech recognition in noise via the German Oldenburg Sentence Test for Children (OlKiSa), lateralization ability, and subjective evaluation of hearing results using self-and third-party assessment questionnaires. Results: Significant improvements of all three aspects of true binaural hearing were found. The most striking improvement was the combined head shadow effect by 2.11 dB (squelch effect: 0.95 dB, summation effect 0.98 dB). An improvement of lateralization ability was also demonstrated. Parents had a high overall level of satisfaction with their children's cochlear implantation. Subjective benefit was verified in all three subscales of the Speech, Spatial, and Qualities of Hearing Questionnaire. No significant difference was found between subjects implanted before the age of 6 with those implanted later. Three of the five subjects with a follow-up of greater than 3 years were limited users or nonusers. Conclusions: Cochlear implant (CI) provision provides children with congenital SSD with significant audiological and subjective benefits which can be seen even in children implanted after the age of 3;6. The problem of limited use and nonuser, however, should not be ignored and has to be considered for further studies.