典型偏头痛发作前经常有视野缺损或暗点出现,少数人可有感觉异常和麻痹,且多发生于单侧。这些现象通常是由于颅内血管收缩所致。已经证明偏头痛患者的脑动脉反应特别敏感,任何一种刺激都可使偏头痛发作,特别年轻妇女,其先驱症状可能异常剧烈和多样。有人认为,与偏头痛有关的一系列症状,如两侧视力缺失、暗点出现、眩晕、语言障碍、意识丧失和末梢症状与体征等,都是由于椎一基底动脉系统受累所致。此外,也曾有紧随偏头痛后而死亡的个案报道。最近研究证明了偏头痛的传统理论,即在疼痛的先兆阶段颅内血流量减少,脑局部缺氧。头痛发作时血流量增加。但是,血管的变化并不总和临床症状完 Prior to the onset of a typical migraine have visual field defects or dark spots appear, a few people may have abnormal sensory and paralysis, and occur more often in one side. These phenomena are usually due to intracranial vasoconstriction. It has been shown that migraine patients are particularly sensitive to cerebral arterial reactions and that any type of irritation can cause migraine attacks. In particular, young women may have unusually vigorous and diverse precursors. Some people think that a series of symptoms related to migraine, such as visual impairment on both sides, dark spots, dizziness, speech disorders, loss of consciousness and peripheral symptoms and signs, are due to the involvement of the vertebrobasilar artery system. In addition, there were also reports of deaths following migraine headaches. Recent studies have demonstrated the traditional theory of migraine, which is a reduction of intracranial blood flow and hypoxic brain in the aura of pain. Blood flow increases during a headache attack. However, the changes in the blood vessels do not total the clinical symptoms