High stimulation rate ABR reveals auditory brainstem conduction abnormalities in vestibular migraine

To explore the application value of high-stimulation-rate auditory brainstem response (ABR) in evaluating auditory pathway conduction in vestibular migraine (VM) patients and to analyze its correlation with clinical symptoms. A prospective case-control study was conducted, including 56 VM patients (56ears) and 56 healthy controls (56 ears). All subjects underwent acoustic immittance testing, pure-tone audiometry, and ABR testing at low (11.1/s) and high (51.1/s) stimulation rates. The interpeak latency variance of wave I–V (ΔI-VIPL) between high and low stimulation rates was calculated, and ≥ 0.28 ms was defined as the abnormal threshold. The Visual Analog Scale (VAS) and Dizziness Handicap Inventory (DHI) were used to evaluate headache intensity and dizziness-related handicap, respectively. The correlations between these scores and ΔI-VIPL were also analyzed. At the low stimulation rate, no significant differences in ABR parameters were observed between the control and VM groups ( P > 0.05). At the high stimulation rate, the latencies of waves III and V, as well as the I–III, I–V and ΔI-VIPLs, were significantly prolonged in the VM group ( P < 0.05). The prevalence of abnormal ΔI-VIPL was 69.64% (39/56), which was significantly higher than that in the control group 12.50%(7/56), P < 0.05. ROC curve analysis for discriminating VM patients from healthy controls showed that the optimal cutoff value of ΔI-VIPL was 0.265 ms (AUC = 0.791, sensitivity 73.2%, specificity 87.5%, P < 0.05). Internal validation with 1,000 bootstrap resamples supported its stability (bootstrap median 0.265 ms, 95% PI 0.215–0.285 ms). Spearman correlation analysis demonstrated that ΔI-VIPL was significantly positively correlated with the total DHI score ( r s =0.623, P < 0.05) and VAS score ( r s =0.534, P < 0.05). High-stimulation rate auditory evoked potential (ABR) can effectively identify abnormal auditory brainstem pathways in VM patients. The ΔI-VIPL parameters show differences among different clinical subtypes, and are closely related to dizziness-related handicap and headache intensity; however, these associations are cross-sectional and should not be interpreted as causal or independently predictive.Therefore, ΔI-VIPL may serve as an auxiliary electrophysiological metric reflecting brainstem auditory conduction stress in VM patients, although further studies with disease controls are required to confirm its clinical utility.