Cochlear implantation in a patient with neurofibromatosis type 1 and profound hearing loss: evidence to support a cochlear site of lesion.

Abstract

To determine the efficacy of cochlear implantation in an individual with neurofibromatosis type 1 and profound hearing loss and to determine, to the extent possible in a living subject, the site of lesion of the hearing loss in an individual with neurofibromatosis type 1. Postoperative assessment of an adult male with neurofibromatosis type 1. The study was completed in the Departments of Otolaryngology and Audiology, University of Massachusetts Medical Center, Massachusetts. One adult male with neurofibromatosis type 1 and bilateral, chiefly profound, sensorineural hearing loss. The subject underwent cochlear implantation as treatment of bilateral, chiefly profound sensorineural hearing loss. Outcome measures include results of electrical auditory brainstem response testing, electrical compound action potential measures, and speech recognition scores. Results of testing revealed expected latencies of waves II, III, and V of the electrical auditory brainstem response, measurable compound action potentials across virtually the entire length of the electrode array, and high levels of open-set, auditory-only speech understanding. This is the first case report describing the outcome of cochlear implantation in a patient with neurofibromatosis type 1. Composite test results support the absence of VIIIth nerve degeneration or other anomalies, indicating a cochlear site of lesion for the hearing loss in this patient. Based on the results of this investigation, standard cochlear implantation should be considered a viable option and the first line of therapy for the treatment of bilateral, severe to profound sensorineural hearing loss in patients with neurofibromatosis type 1 and normal, VIIIth nerve radiographic findings.