The effect of open and closed eyes on vestibular evoked myogenic potential

Introduction: Vestibular evoked myogenic potential is a novel and reliable test which provides diagnostic information about the saccule function and/or inferior vestibular nerve; it also completes the present vestibular tests, and evaluates the sacculocollic reflex. Vestibular evoked myogenic potential amplitude is proportional to the level of background EMG that it shows the necessitate of maintaining constant tonicity of muscles during test recording. Change in eye position results in change in sternocleidomastoid muscle activity and consequently change in vestibular evoked myogenic potential amplitude. Therefore, this study aimed to assess if eye open and closed has effect on vestibular evoked myogenic potential parameters. Materials and Methods: In this cross-sectional study, vestibular evoked myogenic potential was recorded for forty normal subjects, aged 18 to 30 years old, using 500 Hz-tone bursts (95 dBnHL). Results: Considering the results of both ears, there was no significant difference between mean amplitude, p13 and n23 latencies of the two situations (P > 0.05). Conclusion: Eye open and closed has no significant effect on vestibular evoked myogenic potential. Therefore as necessary and for artifact rejection one can be recorded vestibular evoked myogenic potential with close eyes. Keywords: Vestibular evoked myogenic potential, sternocleidomastoid muscle, Eye open/closed