[Auditory neuropathy].
OBJECTIVE
To study the clinical feature and audiological and electrophysiological characteristics of auditory neuropathy.


METHODS
The history, audiometry, stapedial reflex, electrocochleogram, auditory brainstem response, promontory stimulation tests, otoacoustic emissions (OAE) and its contralateral supression tests were studied in 17 cases of auditory neuropathy.


RESULTS
The patients were predominently female teenagers with a history of gradual onset of bilateral hearing loss, pure tone auditometry revealed symmetric ascending audiograms with moderate hearing loss at frequencies below 1 kHz, but relatively normal hearing at 2 kHz and above. Speech reception thresholds were between 40 to 85 dB HL, discrimination score was from 29% to 68%. Stapedial reflex, auditory brainstem response and compound action potentials were absent or threshold elevated disproportionately to the pure tone threshold. All of the patients had normal cochlear microphonics and robust spontaneously and transiently evoked otoacoustic emissions (SOAE and TEOAE), the TEOAE showed no contralateral suppression effects as seen in normal subjects.


CONCLUSIONS
The diagnosis of the disease depends on the discrepancies between subjective and objective hearing and pre-neural and neural responses. The crossed olivocochlear bundle function testing in terms of contralateral acoustic stimulation induced otoacoustic emission reduction is specific for differential diagnosis. There is a need for more awareness of the disease among otolaryngologists and neurologists.
Liang
F
F
Capital University of Medical Sciences, Beijing Tongren Hospital, Beijing Institute of Otolaryngology, Beijing 100730.
Liu
C
C
Liu
B
B
D000158:Acoustic Impedance Tests; D000293:Adolescent; D000328:Adult; D001301:Audiometry, Pure-Tone; D002648:Child; D003051:Cochlea / Q000502:physiology*; D005072:Evoked Potentials, Auditory; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000503:physiopathology; D006801:Humans; D008297:Male; D017084:Otoacoustic Emissions, Spontaneous; D013063:Speech Discrimination Tests; D013069:Speech Reception Threshold Test; D000160:Vestibulocochlear Nerve Diseases / Q000175:diagnosis / Q000503:physiopathology*