Trigeminal neuralgia, migraine and sympathetic hyperactivity in a patient with Parry-Romberg syndrome.

We investigated trigeminal and cervical sympathetic function in a woman with rightsided trigeminal neuralgia, migraine, and atrophy of subcutaneous tissues in the supraorbital region of the right-forehead (Parry-Romberg syndrome). We found loss of sensitivity to innocuous sensations (light touch, warmth, and cold), associated with heightened sensitivity to noxious pressure and heat in the atrophic region in the forehead and, to a lesser extent, in the cheek. Above the sensory detection threshold, light touch and cold evoked abnormal pain sensations that spread from the site of stimulation on the affected side. In addition, weak electrical stimulation of the supraorbital nerve evoked pain and blink reflexes more readily on the affected than unaffected side. The onset of body heating provoked substantial release of sympathetic vasoconstrictor tone on the affected side of the forehead. Similarly, prolonged body heating augmented sweating on the affected side of the forehead, consistent with heightened sympathetic sudomotor activity. These findings support the hypothesis that aberrant trigeminal and cervical sympathetic discharge, possibly resulting from an inflammatory process that attacks cranial blood vessels and nerves, is associated with the atrophic process in Parry-Romberg syndrome.