Assessing otolith dysfunction in Meniere's disease: insights from multi-frequency vestibular evoked myogenic potential testing.

Objective: To investigate the impact of Meniere's Disease (MD) on balance and proprioception by utilising multi-frequency Vestibular Evoked Myogenic Potentials (VEMP) to evaluate otolith function.

Design: Observational study employing the Otolith Tuning Index (OTI) to quantify vestibular function through analysis of VEMP response rates and tuning ratios.

Study sample: A total of 123 participants were included, comprising 94 patients diagnosed with MD and 29 healthy controls. VEMP testing was conducted at frequencies of 500 Hz, 750 Hz, and 1 kHz.

Results: Among MD patients, 69% reported imbalance, with severe cases predominating in advanced stages. The non-response rate for oVEMP at 500 Hz was 73.3% on the affected side, associated with unpredictable falls. Significant correlations were observed between cVEMP non-responses and both disease severity (p = 0.012) and walking imbalance (p = 0.037). oVEMP responses were lowest at 500 Hz, improving at 1 kHz, whereas cVEMP amplitudes peaked at 500 Hz bilaterally. OTI values indicated significant otolith dysfunction on affected sides compared to contralateral sides and controls (p = 0.026, p = 0.032, p < 0.001), with dysfunction worsening with disease progression and age.

Conclusions: The Otolith Tuning Index (OTI) effectively measures otolith dysfunction in MD patients, offering valuable insights to enhance diagnostics, patient management, and treatment planning.