Cluster headache: combined assessment with pupillometry and evaporimetry.

Twenty-nine patients with cluster headache have been examined with the pupillometer and the evaporimeter. Pupils were dilated by sympathicomimetic drugs instilled into the conjunctival sacs, and responses of the two sides were compared. Forehead sweating was stimulated by body heating and by pilocarpine injection, and sweat evaporation on the two sides was compared. Most patients demonstrated the known patterns of hyposecretion on heating, of pilocarpine supersensitivity, and of deficient pupillary dilatation on OH-amphetamine stimulation on the symptomatic side and a supersensitivity of this pupil to phenylephrine. There were deviations from the rule for all methods of testing. Sixteen patients demonstrated a typical supersensitivity response of the pupil and of the sweat glands on the symptomatic side. Six patients had no such response, and seven patients had a discrepancy between the pupillary and the sweat gland response to stimulation, supersensitivity being present in one system only. There was a high degree of concordance between the results of the various methods of examination.