Cluster headache. Our current concepts.

Cluster headache and chronic paroxysmal hemicrania are assumed to be so closely related that they from a classification point of view have been grouped together under the superstructure: cluster headache syndrome. If this grouping will prove to stand the test of time, the pathogenesis of the two subgroups ought to be quite similar. CPH per se has two subgroups: those with and those without mechanical precipitation of attacks. If the aforementioned grouping of CPH is correct, then the CPH subdivision with mechanical precipitation of attacks should also be closely akin to cluster headache. Cluster headache, however, seems to lack the "nuchal" factor. It is felt that "midline structures", like the cavernous sinus, are of importance in cluster headache (cluster headache syndrome?) pathogenesis. In CPH with mechanical precipitation, attacks may be precipitated via "cervical volleys" a.m. Kerr, activating "midline" cavernous sinus structures, while the activation mechanisms in cluster headache is unknown.