The Cluster Headache

Within the group of vascular headaches there stands out a particular variety of headache 1 characterized by a severe throbbing periorbital pain frequently accompanied by lacrimation, conjunctival injection, and nasal congestion. The symptoms are unilateral, abrupt in onset, brief in duration, and appear consistently on the same side. Attacks recur often, usually daily, for a period of one or two months and then subside to return only after an interval of months or years, thus pursuing a time pattern which has suggested the descriptive term cluster headache. 2,3 The literature contains numerous accounts of this type of cephalgia, under a variety of terms including Sluder's headache, sphenopalatine neuralgia, 4 periodic migrainous neuralgia, 5 Harris's neuralgia, 6 ciliary neuralgia, 7 erythromelalgia of the head, 8 histamine cephalgia, 9 Horton's headache, autonomic facial cephalgia, 10 greater superficial petrosal neuralgia, 11 and red migraine. 12 Corresponding and divergent concepts of the nature, etiology,