Comparison of linear motion perception thresholds in vestibular migraine and Menière's disease.

Linear motion perceptual thresholds (PTs) were compared between patients with Menière's disease (MD) and vestibular migraine (VM). Twenty patients with VM, 27 patients with MD and 34 healthy controls (HC) were examined. PTs for linear motion along the inter-aural (IA), naso-occipital axes (NO), and head-vertical (HV) axis were measured using a multi-axis motion platform. Ocular and cervical vestibular evoked myogenic potentials (o/c VEMP) were performed and the dizziness handicap inventory (DHI) administered. In order to discriminate between VM and MD, we also evaluated the diagnostic accuracy of applied methods. PTs depended significantly on the group tested (VM, MD and HC), as revealed by ANCOVA with group as the factor and age as the covariate. This was true for all motion axes (IA, HV and NO). Thresholds were highest for MD patients, significantly higher than for all other groups for all motion axes, except for the IA axis when compared with HC group suggesting decreased otolith sensitivity in MD patients. VM patients had thresholds that were not different from those of HC, but were significantly lower than those of the MD group for all motion axes. The cVEMP p13 latencies differed significantly across groups being lowest in VM. There was a statistically significant association between HV and NO thresholds and cVEMP PP amplitudes. Diagnostic accuracy was highest for the IA axis, followed by cVEMP PP amplitudes, NO and HV axes. To conclude, patients with MD had significantly higher linear motion perception thresholds compared to patients with VM and controls. Except for reduced cVEMP latency, there were no differences in c/oVEMP between MD, VM and controls.