Hemicrania continua and chronic paroxysmal hemicrania: a comparison of pupillometric findings.

Pupillometric studies were carried out in 9 patients with chronic paroxysmal hemicrania (CPH), in 10 patients with hemicrania continua (HC) and in age- and sex-matched controls (n = 12-17). Studies were carried out in the basal condition and after instillation of 2% tyramine, 1% OH-amphetamine, or 1% phenylephrine. The pupillary response to tyramine in HC was more marked than in controls on a percentage increase basis, but not so much when the increment is calculated in absolute values. In this series, there was no asymmetrical response (relative miosis on the symptomatic side) like in previous case reports. The pupil reaction was less in HC than in CPH after hydroxyamphetamine instillation and without any marked asymmetry. There was no definite evidence of supersensitivity to a directly acting sympathicomimetic agent, phenylephrine. No gross abnormalities as regard the sympathetic function in HC was thus observed. The asymmetry on tyramine testing differed in CPH and HC (most marked in HC). No major emphasis should probably be attached to this finding, since on testing with OH-amphetamine, a similar substance, this finding was not reproduced.