Introduction

Vestibular Evoked Myogenic Potentials (VEMP) testing has become a valuable diagnostic tool in the evaluation of Meniere's disease. This non-invasive electrophysiological technique assesses the function of the otolith organs—the utricle and saccule—which are often affected in Meniere's. By recording muscle responses to sound or vibration, clinicians can detect subtle vestibular abnormalities characteristic of this condition.

How VEMP Testing Works

VEMP testing involves delivering acoustic stimuli, typically a loud click or tone burst, to the ear while recording electromyographic activity from the sternocleidomastoid muscle (cervical VEMP) or the extraocular muscles (ocular VEMP). In Meniere's disease, endolymphatic hydrops causes abnormal saccular and utricular function, resulting in altered VEMP responses. The test helps differentiate Meniere's from other vestibular disorders such as vestibular neuritis or benign paroxysmal positional vertigo.

Clinical Utility in Meniere's

Research indicates that cervical VEMP (cVEMP) amplitudes are often reduced or absent on the affected side in Meniere's patients, particularly during acute attacks. Ocular VEMP (oVEMP) may also show abnormalities, reflecting utricular dysfunction. The combination of cVEMP and oVEMP provides a comprehensive assessment of otolith function. Serial VEMP testing can monitor disease progression and response to treatment, such as intratympanic steroid injections or endolymphatic sac surgery.

Interpretation and Limitations

While VEMP is highly sensitive to otolith dysfunction, it is not specific to Meniere's disease. Abnormalities can occur in other conditions like superior canal dehiscence or vestibular migraine. Therefore, VEMP results must be interpreted alongside audiometry and MRI. The test's reliability depends on patient cooperation for adequate muscle activation, and stimulus intensity must be carefully calibrated to avoid discomfort. Despite these limitations, VEMP remains a key component of the neurotologic workup.

Conclusion

VEMP testing offers a window into the functional integrity of the otolith organs in Meniere's disease. Its ability to detect early vestibular involvement makes it a valuable adjunct to audiologic and imaging studies. As research evolves, standardized protocols and refined diagnostic criteria will enhance its role in managing this complex disorder. For patients with suspected Meniere's, VEMP can help confirm the diagnosis and guide therapeutic decisions.