Assessment of the Inter-Frequency Amplitude Ratio (1000/500 Hz) in cVEMP and oVEMP for the Diagnosis of Ménière's Disease.

Objectives: to retrospectively evaluate the clinical relevance of the 1000/500 Hz inter-frequency amplitude ratio (IFAR) in cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs) in patients with unilateral definite Ménière's disease (MD) to identify the pathological ear. Method: cVEMPs and oVEMPs results obtained at 500 Hz and 1000 Hz were retrospectively analyzed in 28 patients with unilateral definite MD. 1000/500 Hz IFAR were calculated and compared for each ear. Spearman correlation tests between patient age and 1000/500 Hz IFAR were also performed. Results: No significant difference was observed between the 1000/500 Hz IFAR calculated in both pathological and healthy ears when the cVEMPs were performed (p = 0.74; Wilcoxon signed-rank test). 1000/500 Hz IFAR results obtained in healthy and pathological ears were also not different for oVEMPs (p = 0.73; Wilcoxon signed-rank test). Analysis of modified 1000/500 Hz IFARs for healthy and pathological ears showed no difference in both cVEMPs and oVEMPs (p = 0.44; p = 0.95, respectively; Wilcoxon signed-rank test). There was a significant positive correlation between IFARs, modified IFARs, and patient age for cVEMPs (p = 0.017; p = 0.012, respectively, Spearman's correlation test). A significant positive correlation was also found between modified IFARs and the subject age in oVEMPs (p = 0.019, Spearman's correlation test). Conclusions: We did not observe any significant increase of 1000/500 Hz IFARs and 1000/500 Hz modified IFARs in ears affected by definite MD compared to healthy ears. Moreover, our research suggests that the age of the participants may influence IFAR results, which may lead to misdiagnosis in the elderly. It is, therefore, essential to conduct further prospective studies in larger cohorts, stratifying results by participant age, to better understand the role of 1000/500 Hz IFAR values in the diagnosis of MD.