Background: The vestibular evoked myogenic potential (VEMP) test is a relatively new diagnostic
tool that is in the process of being investigated in patients with specific vestibular disorders. Briefly,
the VEMP is a biphasic response elicited by loud clicks or tone bursts recorded from the tonically
contracted sternocleidomastoid muscle, being the only resource available to assess the function of
the saccule and the lower portion of the vestibular nerve. Vestibular evoked myogenic potentials
(VEMPs) are a useful and increasingly popular component of the neuro-otology test battery. These
otolith-dependent reflexes are produced by stimulating the ears with air-conducted sound or skull
vibration and recorded from surface electrodes placed over the neck (cervical VEMPs) and eye
muscles (ocular VEMPs). VEMP abnormalities have been reported in various diseases of the ear and
vestibular system, and VEMPs have a clear role in the diagnosis of superior semicircular canal
dehiscence. However there is significant variability in the methods used to stimulate the otoliths
and record the reflexes. This review discusses VEMP methodology and provides a detailed
theoretical background for the techniques that are typically used. The review also outlines the
common pitfalls in VEMP recording and the clinical applications of VEMPs in children.
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