Auditory Neuropathy Accompanying Bilateral Vestibular Hypofunction / 대한이비인후과학회지

ABSTRACT

Auditory neuropathy is a term used to describe the auditory neural pathway abnormality in the presence of cochlear outer hair cell functions. It is reported that 9 of 14 auditory neuropathy patients had abnormal findings in the caloric test. The authors present a case of auditory neuropathy accompanying bilateral vestibular loss. The patient was a 33-year-old female who had a family history of her mother having bilateral hearing loss. Auditory brain stem response (ABR) and otoacoustic emission (OAE) were checked and the results were compatible with auditory neuropathy. To evaluate her vestibular function, bithermal caloric test, rotatory chair, fundus photograph, vestibular evoked myogenic potential (VEMP), oculomotor test were checked. Laboratory findings were compatible with bilateral vestibular loss involving both superior and inferior division of vestibular nerve territory. Though bilateral vestibular hypofunction was substantial, she did not report any subjective discomfort from bilateral vestibular loss. Considering the presence of OAE and the abnormal findings in ABR in this patient, the pathologic lesion seems to be in the vestibular neural pathway rather then in the vestibular end organs. Routine vestibular evaluation seems to be necessary for comprehensive evaluation of the auditory neuropathy patients.