Variability of the blink reflex in patients with migraine

Abstract Background and purpose Sensitization of brainstem trigeminal nuclei and activation of the trigeminovascular system are thought to play an important role in migraine. The blink reflex has become a valuable tool for investigating trigeminal nerve function. The aim of the study was to assess the differences in electrophysiological examinations of the trigeminal nerve (blink reflex) in a group of patients with migraine in comparison with a healthy control group. Material and methods The examination was conducted among 58 patients. Patients were diagnosed in the Polyclinic or hospitalized in the Department of Neurology of Warsaw Medical University in Bielanski Hospital. The study group included 29 patients suffering from migraine (diagnosed according to the International Classification of Headache Disorders, 2 nd edition) and 29 patients without headaches served as controls. All patients underwent neurological examination and magnetic resonance imaging to identify organic disorders. The blink reflex was tested among all patients in accordance with electrophysiological laboratory standards. Results The latency of the R1 response was significantly shorter among patients with migraine. The latency of R2 and R2’ responses was similar in patients and controls. A significant inverse correlation was observed between latency of R2 and R2’ responses and frequency of migraine attacks. Conclusions The inverse correlation between the frequency of attacks and the latency of R2 and R2’ responses of the blink reflex confirms the abnormal eaxcitability induced by the high frequency of migraine attacks.