Vestibular evoked myogenic potentials.

Vestibular Evoked Myogenic Potentials (VEMP) are commonly recorded in patients experiencing vertigo or chronic instability. This test evaluates the patient's otolith function and is often combined with both Videonystagmography and Video Head Impulse Test. VEMP is a simple, reproducible test, in the absence of any pre-existing conductive hearing loss. Cervical VEMP explore both saccular function and the inferior vestibular nerve, whereas ocular VEMP assess utricular function and the superior vestibular nerve. In combination with previously described tests, VEMP allows characterization of vertigo and provides support for the diagnosis of superior semicircular canal dehiscence syndrome, Menière's disease, vestibular neuritis, vestibular schwannoma or idiopathic bilateral vestibulopathy. A good knowledge of these electrophysiological tests is essential in order to precisely assess the presence or absence of vestibular function impairment. We describe the test recording technique and the most common pitfalls in interpretation of the results. We then outline the results observed in various diseases impacting vestibular function.