Optimal Electrode Configuration for Masseter Vestibular-Evoked Myogenic Potential: A Comparison Between Zygomatic and Forehead Electrode Montages.

Background: The masseter vestibular-evoked myogenic potential (mVEMP) is a short-latency electromyographic potential that assesses the integrity of the vestibule-masseteric reflex pathway. Due to limited normative studies, there is no optimal mVEMP protocol to be implemented clinically. Apart from the conventional electrode configuration, a naïve montage referred to as the forehead reference has been used in recent studies. Purpose: This study compared latency and amplitude parameters of mVEMP between the zygomatic and forehead electrode configurations to address the optimal electrode montage to elicit mVEMP. Research Design: Cross-sectional research study. Study Sample: Thirty healthy participants (mean age: 23.3 years; 14 males and 16 females). Data Collection and Analysis: Participants underwent mVEMP testing under two-electrode montage conditions (zygomatic and forehead reference electrode montages). Results: Statistically significant increases in P1 latency, decrease in N1 latency, reduction of P1-N1 interpeak interval, enlargement of both unrectified and electromyography-rectified amplitudes, and lower interaural amplitude asymmetry ratio were observed for the forehead electrode montage compared to the conventional zygomatic montage. Conclusions: mVEMP response waveforms obtained using forehead reference electrode montage are superior to the zygomatic montage. Hence, the forehead montage is suggested for further research on mVEMP.