Vestibular evoked myogenic potential findings in multiple sclerosis.

INTRODUCTION Multiple sclerosis is an inflammatory disease involving the occurrence of demyelinating, chronic neurodegenerative lesions in the central nervous system. We studied vestibular evoked myogenic potentials (VEMPs) in this pathology, to allow us to evaluate the saccule, inferior vestibular nerve and vestibular-spinal pathway non-invasively. METHODS There were 23 patients diagnosed with multiple sclerosis who underwent VEMP recordings, comparing our results with a control group consisting of 35 healthy subjects. We registered p13 and n23 wave latencies, interaural amplitude difference and asymmetry ratio between both ears. Subjects also underwent an otoscopy and audiometric examination. RESULTS The prolongation of p13 and n23 wave latencies was the most notable characteristic, with a mean p13 wave latency of 19.53 milliseconds and a mean latency of 30.06 milliseconds for n23. In contrast, the asymmetry index showed no significant differences with our control group. CONCLUSIONS In case of multiple sclerosis, the prolongation of the p13 and n23 VEMP wave latencies is a feature that has been attributed to slowing of conduction by demyelination of the vestibular-spinal pathway. In this regard, alteration of the response or lack thereof in these potentials has a locator value of injury to the lower brainstem.