The Auxiliary Diagnostic Value of Microsaccades in Vestibular Migraine.

Abstract

This study aims to quantitatively analyze vestibulo-ocular reflex (VOR) gain and saccade characteristics during video head impulse testing (vHIT) in patients with vestibular migraine (VM), providing evidence for clinical diagnosis. This study included 30 definite VM patients (60 ears) and 30 healthy controls (60 ears). The function of six semicircular canals (SCCs) was evaluated by vHIT. Quantitative parameters of VOR gain and saccades were compared between groups. Benjamini-Hochberg correction was applied (q < 0.05 considered significant). No significant differences in VOR gains for all SCCs were found between groups (q > 0.05). However, in the analysis of saccade parameters, the VM group showed higher peak velocity (q = 0.03) and shorter latency (q = 0.03). No group differences were observed in saccade duration or frequency for lateral SCCs, nor in any saccade parameters for vertical SCCs. ROC analysis identified optimal cutoffs for the first lateral SCC saccade: peak velocity of 83.69°/s (AUC: 0.668, sensitivity: 0.586, specificity: 0.8) and latency of 295.45 ms (AUC: 0.666, sensitivity: 0.69, specificity: 0.582). Although VOR gains in VM patients fall within the normal range, they exhibit pathological microsaccades that differ from those of healthy individuals, characterized by lateral SCC saccades with "high velocity and short latency." These quantitative saccade parameters hold promise as supplementary objective indicators to complement traditional VOR gain, offering auxiliary evidence for the clinical diagnosis of VM.