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PubMed · 8841698

Localizing retrocochlear hearing loss.

B E Hirsch·J D Durrant·S Yetiser·D B Kamerer·W H Martin
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Abstract

PURPOSE: The origin of acute/sudden hearing loss is multifactorial. The association of vestibular symptoms does not necessarily isolate the pathologic condition to the inner ear. The audiogram provides a screen for differentiating conductive from sensorineural loss but often fails to provide more localizing information. METHODS: Three unusual patients with a variety of retrocochlear presentations of hearing loss are presented. Along with conventional auditory brainstem response (ABR) testing, newer auditory tests, including otoacoustic emissions and three-dimensional ABR analysis, can facilitate site-of-lesion testing. Magnetic resonance imaging (MRI) also provides graphic documentation for sources of retrocochlear hearing loss. RESULTS: One patient had gamma-knife treatment of an arteriovenous malformation, incurring a localised lesion to the inferior colliculus contralateral to the side of hearing loss. This effectively eliminated wave V, as confirmed by three-dimensional ABR analysis. A second patient with human immunodeficiency virus developed sudden complete hearing loss with retained otoacoustic emissions, confirming a retrocochlear lesion. A third patient with acute otitis media with sudden hearing loss and vertigo had an abnormal ABR and "mass lesion" on MRI. Hearing subsequently returned to normal, as did a repeated scan. CONCLUSIONS: The unique aspects of each case of retrocochlear hearing loss and the applied auditory electrophysiologic tests are reviewed.

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AdultAudiometry, Evoked ResponseCochleaEvoked Potentials, Auditory, Brain StemFemaleHearing Loss, SensorineuralHumansInferior ColliculiMagnetic Resonance ImagingMaleMiddle AgedSpeech Discrimination TestsCase ReportsJournal Article

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BibTeXRIS

B E Hirsch, J D Durrant, S Yetiser, D B Kamerer, W H Martin. 1996. Localizing retrocochlear hearing loss.. https://pubmed.ncbi.nlm.nih.gov/8841698/

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