Neurovascular headache and a midbrain vascular malformation: evidence for a role of the brainstem in chronic migraine.

Migraine is a common, disabling form of primary headache that has been linked by functional imaging studies to activation in the rostral brainstem. In specialty clinics migraine is most commonly seen in association with frequent less feature full headache that has been called transformed migraine or more recently termed chronic migraine. A patient is described with frequent migraine, 3 days per week, and less feature full headaches on other days. The patient has a cavernoma in the midbrain that has bled. She was previously headache free and now has contralateral daily headache. The patient supports the functional imaging observations from positron emission tomography (PET) that the rostral brainstem is pivotal in migraine pathophysiology, particularly the contralateral midbrain periaqueductal grey matter. Moreover, the patient's lesion provides biologically plausible support that a single entity causes her clinical presentation: chronic migraine, not two-disorders, migraine and tension-type headache.