[Unilateral auditory neuropathy. A rare differential diagnosis of unilateral deafness].

Auditory neuropathy presents with normal otoacoustic emissions combined with pathological findings in brainstem evoked response audiometry. Normally, the auditory neuropathy is bilateral. We report about a 9 year old child where we could diagnose a unilateral deafness in spite of regular TEOAE and DPOAE. No reproducible biosignals were seen when the right ear was stimulated with alternating click stimuli at a level of 80 dB. On the left side, the latency of the potentials was normal. A cranial MRI showed normal anatomy. In order to determine a unilateral deafness, objective tests (e.g., OAE, BERA) and subjective tests should be used.