Evaluation of the otolith function using c/oVEMPs in patients with Ménière's disease.

BACKGROUND: Cervical and ocular vestibular evoked myogenic potentials (c/oVEMPs) reflect otolith function. Up-to-date, there are no published reports on the systemic evaluation of otolith function in Ménière's Disease (MD) nor are there any reports on the differences in VEMPs between patients with early and late stage MD. The aim of this study was to evaluate the difference in c/oVEMPs between patients with MD and normal controls, as well as between patients with early and late stage MD.

METHODS: Thirty patients with unilateral MD and thirty healthy subjects (as normal controls) were prospectively enrolled. c/oVEMPs using 500 Hz tone-burst stimuli were performed. VEMP tests were repeated 3 times on each subject to ensure reliability and reproducibility of responses. VEMPs were defined as present or absent. Abnormal VEMP was defined by lack of VEMP response.

RESULTS: In the control group, abnormal cVEMPs and oVEMPs responses were detected in 6.67 and 3.34 % respectively. In MD patients (20 with early stage MD [ES-MD], 10 with late stage MD [LS-MD]), abnormal cVEMPs and oVEMPs responses were detected in 40 and 16.7 % respectively. More patients with MD showed abnormal responses in c/oVEMPs as compared to the control group (p < 0.05). cVEMPs was more often abnormal as compared to oVEMPs in MD patients (p < 0.05). There was a significant difference in abnormal cVEMP responses between ES-MD patients (25 %) and LS-MD patients (70 %) (p < 0.05). Difference in abnormal oVEMP responses (ES-MD, 5 %; LS-MD, 40 %) was significant (p < 0.05).

CONCLUSION: An increased occurrence of abnormal c/oVEMP recordings appeared in MD patients, possibly as a result of hydrops of the otolith. cVEMPs were more often abnormal in MD patients as compared to oVEMPs, suggesting that saccular dysfunction may be more common than utricular dysfunction. Furthermore, o/cVEMP abnormalities in the LS-MD group were significantly higher than those in the ES-MD group, suggesting the trend that otolith damage is gradually increasing with the aggravation of cochlear injury in MD.