133. Traumatic Bernard–Horner syndrome. Uncoupling of sudomotor and vasoconstrictor activity

Here we describe a patient with Bernard Horner syndrome who underwent a detailed neurophysiological study with Sympathetic Skin Response and infrared Thermography. One 32-year-old male patient with traumatic complete Bernard Horner syndrome, following neck injury during a motorcycle accident. The patient presented with miosis, ptosis, enophthalmos and anhidrosis of the left hemiface following a trauma of left neck. SSR to electric and acoustic stimuli was absent on the left forehead, but was unremarkable over the right face and the palms. Infrared Thermography revealed hypothermia over the left head and neck. These findings were unchanged 5 months after the trauma. In our patient, traumatic paralysis of sympathetic fibers supplying the head and the neck, led to long-lasting abolition of hemiface sweating associated with increased skin vasoconstriction in the anhidrotic area. The present report points out that sympathetic denervation affects sudomotor cholinergic fibers differently from vasoconstrictor adrenergic fibers. At 5 months post-trauma, sudomotor function was severely reduced, whereas vasoconstriction was re-established.