Unilateral auditory neuropathy: case study

This article reports on an 11-year-old boy who was diagnosed with unilateral auditory neuropathy. After failing his annual medical and school hearing screenings, he was referred for audiologic testing, which identified a profound sensorineural hearing loss in his left ear that has remained stable for the past 3 1/2 years. Subsequently, otoacoustic emissions revealed findings that were consistent with an auditory neuropathy. Neurologic evaluation was remarkable only for a left ear hearing loss. Radiologic studies were unremarkable. Auditory neuropathy is a condition in which patients, on audiologic evaluation, are found to have normal outer hair cell function and abnormal neural function at the level of the eighth nerve. These patients, on clinical testing, are found to have normal otoacoustic emissions, whereas auditory brainstem response audiometry reveals the absence of neural synchrony. Unlike space-occupying lesions, radiologic evaluation reveals normal results. This case is noteworthy because only a handful of the cases of auditory neuropathy reported to date have been unilateral.