Effect of Electrode Montage and Head Position on Air-Conducted Ocular Vestibular Evoked Myogenic Potential.

Purpose: The purpose of this investigation was to identify the optimal recording parameters for evoking the ocular vestibular evoked myogenic potential (oVEMP) using air-conduction stimuli.

Method: Subjects were 17 otologically and neurologically intact adults (age: M = 24.18 years, SD = 1.91 years). The oVEMP responses were elicited using a 500-Hz tone burst air-conduction stimulus presented at an intensity of 95 dB nHL. The setting was a balance function laboratory that was part of a large tertiary care otology clinic.

Results: The oVEMP electrode montage and body position that yielded the largest oVEMP amplitude was the belly-tendon montage (Sandhu, George, & Rea, 2013), recorded with the subject in the sitting position. The N1 latency recorded with the belly-tendon montage was significantly shorter than that recorded for the infraorbital montage in both the sitting and supine positions.

Conclusion: The belly-tendon recording montage with the subject sitting yields significantly larger oVEMP amplitudes and shorter N1 latencies than do traditional bipolar infraorbital recordings.