Vestibular Evoked Myogenic Potentials Show Altered Tuning in Patients with Ménière’s Disease

TLDR

The vestibular evoked myogenic potential (VEMP) reflects a saccule‑driven vestibulocollic reflex that can be measured as inhibition of the ipsilateral sternocleidomastoid muscle and is used to assess saccular integrity. The study tests whether cochleosaccular hydrops in Ménière’s disease alters saccular motion and thereby changes VEMP dynamics. VEMP thresholds, amplitudes, and latencies were recorded in 14 normal volunteers and 34 unilateral Ménière’s patients using ipsilateral broadband click and tone‑burst stimuli from 250 to 4000 Hz, and the data were analyzed for age, hearing loss, and audiometric configuration effects. Affected Ménière’s ears showed significantly higher VEMP thresholds and reduced 500 Hz tuning compared to normals and unaffected ears, while unaffected ears also exhibited elevated thresholds, supporting the hypothesis of altered saccular mechanics due to hydropic distention and suggesting occult hydrops or binaural interactions.

Abstract

Acoustic stimulation of the saccule gives rise to a vestibulocollic reflex, the output of which can be measured in the neck as inhibition of activity in the ipsilateral sternocleidomastoid muscle. This vestibular evoked myogenic potential has been promoted as a means of assessing integrity of saccular function. In this study, we test the hypothesis that the cochleosaccular hydrops of Ménière's syndrome leads to alterations in saccular motion that change the dynamics of the vestibular evoked myogenic potential.Prospective cohort study.Large specialty hospital, department of otolaryngology.Fourteen normal adult volunteers and 34 consecutive consenting adult patients with unilateral Ménière's disease by American Academy of Otolaryngology-Head and Neck Surgery diagnostic criteria.All subjects underwent vestibular evoked myogenic potential testing using ipsilateral broadband click and short tone-burst stimuli at 250, 500, 1,000, 2,000, and 4,000 Hz.Threshold, amplitude, and latency of vestibular evoked myogenic potential responses in normal and Ménière's affected and unaffected ears.Vestibular evoked myogenic potential was present in all ears tested. Normal subjects show a frequency-dependent vestibular evoked myogenic potential threshold, with best response ("frequency tuning") at 500 Hz. Compared with normal subjects and unaffected ears of Ménière's subjects, affected Ménière's ears had significantly increased vestibular evoked myogenic potential thresholds. Affected Ménière's ears showed threshold shifts at all frequencies and there was less tuning apparent at 500 Hz. Unaffected ears of Ménière's subjects also showed significantly elevated vestibular evoked myogenic potential thresholds compared with normal subjects. Analyses of vestibular evoked myogenic potential thresholds for effects of age, hearing loss, and audiometric configuration showed no significant differences.Ménière's ears display alterations in vestibular evoked myogenic potential threshold and tuning, supporting our hypothesis of altered saccular motion mechanics arising from hydropic distention. Unaffected ears of unilateral Ménière's subjects show similar changes, though to a lesser degree. This finding may be because of occult saccular hydrops in the asymptomatic ear or binaural interactions in the vestibular evoked myogenic potential otolith-cervical reflex arc.