Frequency Amplitude Ratio of Ocular Vestibular Evoked Myogenic Potential in Different Age Groups

Abstract

BACKGROUND: High levels of sound intensity can be detected by the vestibular system. It is a clinical method used to assess the vestibular
system’s response to sound stimulation. In healthy individuals, research has indicated that the use of low-frequency stimuli results in decreased
vestibular evoked myogenic potential (VEMP) thresholds, especially a 500 Hz tone-burst. As people age, their frequency tuning changes, moving
towards higher frequencies.

METHODS: Eighty healthy participants participated in this cross-sectional investigation. Both air conduction (AC) and bone conduction (BC) were
used as stimulation methods in the ocular VEMP (oVEMP) test. The following oVEMP parameters were assessed in the study: the inter-frequency
peak amplitude ratio (FAR). Furthermore, a rectified FAR (Frequency Amplitude Ratio)—a technique that normalizes the VEMP response amplitude according to the strength of muscle contraction as determined by EMG (Electromyogram) —was examined.

RESULTS: Statistically significant differences in FAR and rFAR (rectified Frequency Amplitude Ratio) of oVEMP were observed among the 5 age
groups when using both AC and BC stimuli.

CONCLUSION: This study used both AC and BC stimuli to determine age norms for the FAR (1000/500 Hz) of oVEMP. When compared to younger
age groups, participants over 50 had much greater FAR and corrected FAR values. Comparable FAR results were obtained from both AC and BC
stimuli, suggesting that either approach can be utilized for testing.