OCULOCEPHALIC SYMPATHETIC DYSFUNCTION IN POSTTRAUMATIC HEADACHES

Oculocephalic sympathetic functions were assessed in five patients wit h posttraumatic headaches using the thermoregulatory sweat test and bi ochemical pupillary responses. Four patients demonstrated bilateral sy mpathetic dysfunction following whiplash injury, and one patient demon strated unilateral sympathetic dysfunction following forehead injury. Biochemical pupillary responses were diagnostic in the early posttraum atic period, while the thermoregulatory sweat test was abnormal up to 56 months following the injury. This study documents serious injury to the cervical sympathetic nerves in patients with posttraumatic headac hes following whiplash injury, and shows the reliability of the thermo regulatory sweat test in identifying patients with long-term oculoceph alic sympathetic dysfunction. It also shows dissociated postganglionic cranial sympathetic dysfunction. Our experience and a review of the p ertinent literature shows no convincing clinical or experimental evide nce to establish oculocephalic sympathetic dysfunction as a direct cau se of head pain, but it may exert an effect on cephalic pain through t he trigeminovascular system.