Cochlear Implantation in Craniometaphyseal Dysplasia

Objective Describe the first case of cochlear implantation (CI) for auditory rehabilitation of a patient with craniometaphyseal dysplasia (CMD) and progressive mixed hearing loss. Patients A 65-year-old woman with known autosomal dominant CMD presented with progressive mixed hearing loss and declining benefit from conventional hearing aids. Computed tomography and magnetic resonance imaging revealed hyperostosis of the entire craniofacial skeleton. Hearing evaluation demonstrated pure-tone thresholds in the profound range bilaterally by air conduction, and bone conduction thresholds that matched aided thresholds for her left ear, though testing was somewhat limited by inability to mask at high air-conduction thresholds. CI candidacy testing confirmed poor word and sentence scores in the right ear. Intervention Due to the inability to access the cochlea via a conventional mastoidectomy and facial recess approach, cochlear implantation via a postauricular subtotal petrosectomy approach with ear canal overclosure was performed. Main outcome measures Post-implantation word and sentence testing. Results Despite extensive internal auditory canal stenosis, the patient demonstrated excellent early speech understanding results 5 weeks after device activation. Postimplantation audiologic evaluation showed thresholds between 20 and 30 dB HL from 250 to 6000 Hz. Word and sentence testing scores were 76% Consonant-nucleus-consonant in quiet (up from 2% preoperatively) and 77% AzBio sentences in quiet (up from 10% preoperatively). Conclusion This report describes the first description of CI for CMD. Despite the extensive radiologic abnormalities, the patient has demonstrated excellent benefit from implantation. Further study of rare temporal bone dysplasias, such as CMD, is critical to better characterize the progression of otologic disease and determine optimal treatment.