Facial temperature in migraine, tension-vascular and tension headache.

The relationship between clinical features and changes in the extracranial circulation was studied during 209 separate attacks of headache affecting the anterior part of the head. Extracranial vascular changes were assessed thermographically and by the change in headache intensity when pressure was applied over the superficial temporal and common carotid arteries. In unilateral headaches, increased heat loss from the affected frontotemporal region was observed most frequently in attacks which were temporarily relieved by compression of the superficial temporal artery; thermographic asymmetry disappeared as the headache abated. Although such headaches were associated more frequently with migrainous features than attacks which did not respond to arterial compression, many headaches with clinical features of migraine had no vascular component detectable by thermography or vascular compression. Furthermore, the response to arterial compression was not consistent from one headache to another in the same patient. It was concluded that extracranial vascular changes recur intermittently in headache-prone patients, depending on the severity of pain and association with other features commonly regarded as migrainous. However, there was no clear demarcation point between entities diagnosed clinically as "migraine" and "tension headache".