The analysis of many different studies on the characteristics of headaches provides data to help predict the type of cerebrovascular disease according to headache patterns. Lack of headache at onset, sentinel headache, or associated vomiting is predictive of ischemic stroke. A history of throbbing headache is predictive of developing headache during a stroke. A headache preceding the cerebrovascular event (sentinel headache) has been a common occurrence in most studies, reported in up to 60% of patients. The coexistence of headache and stroke encompasses a large spectrum of possibilities, including stroke caused by migraine headache, migraine developing after a stroke, and non-migraine headache occurring in relation to stroke. A higher incidence of patent foramen ovale (PFO) in migraine with aura patients suggests that cardiac microemboli affecting the vertebrobasilar circulation may participate in the migrainous mechanisms of these patients.