Bilateral Sympathetic Dysfunction in Post‐Traumatic Headaches

SYNOPSIS Two patients developed generalized throbbing headaches, tenderness of the anterior neck and unilateral ptosis following whiplash injury. They were systematically evaluated for involvement of the central nervous system, carotid arteries, vagi and cervical sympathetic nerves. Biochemical study of pupils revealed bilateral postganglionic Horner's syndrome. Thermal‐induced facial sweating showed supraorbital anhidrosis. Follow‐up 18 to 54 months after injury demonstrated partial improvement in pupillary functions and headaches but persistent supraorbital anhidrosis. Pertinent literature on sympathetic dysfunction and post‐traumatic headaches is reviewed, and the reasons and implications for sympathetic involvement in hyperextension‐hyperflexion injury are discussed.