VEMP Stimuli: A Guide to Ensuring Patient Safety

By Samantha Kleindienst Robler, Cory Portnuff, and Jamie M. Bogle

This article is a part of the May/June 2018, Volume 30, Number 3, Audiology Today issue.

Vestibular-evoked myogenic potentials (VEMPs) are electrophysiological measures of saccular and utricular reflex pathways. These potentials are currently the only method available to gain information on these important balance organs in the clinic. VEMPs are recorded easily and have been accepted widely due to the novel information they provide to the vestibular diagnostic evaluation. In most clinics in the United States, VEMPs are recorded using air-conducted short-duration tone bursts or clicks (Rosengren et al, 2009). To record these responses, however, high-intensity stimuli between 120 and 140 dB pSPL are required, reaching the upper limit of what is considered safe exposure.

During VEMP testing, the cochlea is exposed to high sound pressure levels (Krause et al, 2013; Mattingly et al, 2015; Stromberg et al, 2015), but unfortunately, there is limited reported information about the possible effects of VEMP stimuli on the cochlea. Several studies have evaluated the effects of this stimulus on cochlear function with results showing decreased distortion product otoacoustic emissions (DPOAEs) after VEMP testing, but with no significant changes in hearing thresholds (Krause et al, 2013; Stromberg et al, 2015).

One report identified a case study of sudden permanent bilateral sensorineural hearing loss after VEMP testing with stimulation intensities ranging between 128-135 dB pSPL (Mattingly et al, 2015). Despite the limited information, these reports demonstrate a concern for those completing VEMP testing, indicating that we must take care to safely measure VEMP responses without possible damage to the cochlea.