RESUMEN
Abstract Objectives: Although the cause of Meniere's disease (MD) is not fully understood, endolymphatic hydrops is widely believed to be responsible for MD. Previous studies have used Air-Conducted Sound (ACS)-induced Vestibular Evoked Myogenic Potentials (VEMPs) to evaluate otolithic function in patients with MD. However, the use of Galvanic Vestibular Stimulation-VEMPs (GVS-VEMPs) with other vestibular tests in MD has been rare. This study aimed to explore the application of galvanic VEMPs in assessing MD. Methods: Normal individuals and patients with unilateral definite MD were included in this retrospective study. All participants underwent pure tone audiometry. Ocular and cervical VEMPs induced by GVS, and ACS were recorded. The characteristic parameters of VEMPs (n1 latency, p1 latency, amplitude, and AR) were analyzed. Results: The provocation rates of GVS-VEMPs did not differ between MD patients and control individuals. Compared with ACS, GVS could evoke potentials with longer latencies. MD patients presented GVS-VEMPs with lower amplitudes and ACS-cVEMP with shorter latencies and had a higher response rate in GVS-oVEMP. However, no differences or correlations were found in the characteristic parameters of GVS-VEMPs among the different stages of MD. Conclusions: GVS is as effective as ACS for inducing VEMP, and GVS-VEMP recording can detect retrolabyrinthine degeneration in MD. Further research is needed to assess the utility of GVS-VEMP in the evaluation of MD severity. Level of evidence: Level 4.
RESUMEN
Vestibular stimulation by air-conducted sound (ACS), bone-conducted vibration (BCV), or electrical currents (galvanic stimulation) elicits vestibular evoked myogenic potentials (VEMPs) that are now widely used to assess otolith function. Conventional cervical VEMPs, which are a manifestation of the vestibulocollic reflex, measure electromyographic activity from surface electrodes placed over the tonically activated sternocleidomastoid muscles. VEMPs can also be recorded from the extraocular muscles using surface electrodes placed over the inferior oblique and inferior rectus muscles, known as ocular VEMPs (oVEMPs). oVEMPs are a manifestation of the vestibulo-ocular pathways. We describe herein the neurophysiological properties of VEMPs obtained in response to ACS and BCV stimulation, and outline the known characteristics of VEMPs in central and peripheral disorders commonly encountered in neuro-otology clinics.