Functional and imaging anomalies of the vestibular system in motion sickness: a clinical observation study.

Objective: The aim of this study is to investigate the differences in vestibular organ function tests and the temporal bone computed tomography (CT) findings between healthy individuals and patients with motion sickness (MS), providing a basis for establishing functional and imaging diagnostic criteria for MS.

Method: Vestibular organ function tests and temporal bone CT imaging were performed on patients in the MS group (n = 50) and healthy individuals in the control group (n = 50). Functional and imaging anomalies of the vestibular organ were identified and their features and patterns were analyzed. Patients with MS were further stratified based on severity to examine whether temporal bone CT findings varied across severity grade, and indexes of diagnostic significance were identified.

Results: Comparisons of vestibular function tests revealed significantly lower bilateral vestibular evoked myogenic potential (VEMP) amplitudes in the MS group compared to the control group, with statistical significance (P < 0.05). The severity of MS demonstrated a positive correlation with reductions in bilateral cervical VEMP (cVEMP) amplitudes (P < 0.05). Video head impulse test (v-HIT) results indicated statistically significant differences in the gains of the left anterior, right horizontal, and left posterior semicircular canals (P < 0.05). There were significant differences in the bilateral vestibular caloric test (CT) values (P < 0.05). In terms of the temporal bone CT findings in the two groups, the detection rate of high jugular bulb combined with sinusitis, poor mastoid pneumatization, diploetic mastoid, or sclerotic mastoid was higher in patients with MS than in the healthy control group. Additionally, the detection rate of temporal bone anomalies in CT scans was significantly higher in the very severe and severe MS groups compared to the mild and moderate MS groups.

Conclusion: In this study, we found that patients with MS exhibited functional and structural anomalies in vestibular function and temporal bone CT findings, which were correlated with the severity of MS. These findings suggest that vestibular function tests and temporal bone CT imaging can be used as objective reference indexes for the diagnosis of MS and assessment of its severity.