Evaluation of ocular and cervical vestibular evoked myogenic potentials in a conductive hearing loss model

OBJECTIVE: To investigate the effects of conductive hearing loss (CHL) on vestibular evoked myogenic potentials (VEMPs) using a simulated CHL model, and to provide the basis for future studies. METHODS: Twenty-one healthy subjects were recruited in this study. We measured ocular VEMPs (oVEMPs) and cervical VEMPs (cVEMPs) in these subjects by air-conduction sound (ACS) stimulation. CHL was simulated later by blocking the right external auditory canal with a soundproof earplug to evaluate its impacts on VEMPs. Subjects' responses before simulated CHL served as the control, and were compared to their responses following simulated CHL. RESULTS: oVEMPs following simulated CHL showed decreased response rate, elevated thresholds, attenuated amplitudes and prolonged N1 latencies compared with those before simulated CHL, and the differences were statistically significant. Similarly, cVEMPs following simulated CHL also showed decreased response rate, elevated thresholds and attenuated amplitudes, with prolonged P1 latencies compared with those before simulated CHL, although only differences in response rate, threshold and amplitude were significant. CONCLUSIONS: Conductive hearing loss affects the response rate and other response parameters in oVEMPs and cVEMPs.