Implantation of the malformed cochlea

Objective: This study assesses the results of cochlear implantation in chil dren with cochlear malformations. Study Design: Retrospective, matched-pairs analysis of prospectively collec ted data. Setting: University-based regional cochlear implant center. Patients: Seventeen children with osseous cochlear malformations who had un dergone implantation were matched and compared with a group of children wit h normal cochleae who had undergone implantation. Interventions: All subjects received a multichannel cochlear implant and ha bilitation. Main Outcome Measures: All subjects were tested with the Early Speech Perce ption test, and the Glendonald Auditory Speech Perception tests for words a nd sentences. Patients were classified in a standardized speech perception category based on performance on the Early Speech Perception test. Results: All subjects demonstrated improving performance on all measures of speech perception over time. Overall, the two groups showed no statistical ly significant differences in performance at 6 and 24 months. However, subj ects with malformed cochleae evidenced slower rates of improvement than did their matched control subjects. Subjects with more severe malformations de monstrated poorer performance, but this may have been attributable to preop erative factors rather than to implant performance. Conclusions: Children with radiographic cochlear malformations benefit from cochlear implantation with multichannel devices. They ultimately perform a s well as their matched counterparts with normal cochleae, although they ma y improve more slowly over time.