The pathophysiology of migraine includes the vascular theory, the trigeminovascular theory, and cortical spreading depression; however, the pathophysiology of a spontaneous migraine attack has not yet been clarified. The vascular theory became negative, and it was considered that the pain of migraine was not associated with vascular expansion. However, recent studies have again attracted attention toward the vascular theory of migraine. The aim of the present study was to provide effective tools for monitoring hemodynamic changes in the cortical and scalp surface during migraine attack and treatment. Using a near-infrared spectroscopy system and laser doppler skin blood flow (SkBF) monitoring device in combination, we monitored changes in extra- and intracranial vasculature upon sumatriptan injection during spontaneous migraine attack. There was a marked reduction of oxy-Hb/SkBF in all patients after sumatriptan injection, and this was consistent with pain relief. Moreover, the changes in oxy-Hb and SkBF were significantly correlated. In contrast, saline injection did not cause any significant changes.
These data suggest that sumatriptan induces the vasoconstriction of the vascular bed region, including the arteriovenous anastomosis in the scalp and cortex. On the basis of these data, we suggest that it is now justifiable to reconsider the vascular theory of migraine.
