Pre-symptomatic neurological involvement in Behcet's disease: the diagnostic role of magnetic transcranial stimulation.

Twenty Behcet's disease (BD) patients with or without neurologic signs and symptoms were studied by means of magnetic transcranial stimulation. The most frequent abnormalities were an increase of motor evoked potential latency and a delay of central motor conduction time (CMCT). In 5 out of 9 BD patients with pyramidal signs central motor conduction changes were present. Furthermore, 2 out of 7 patients without neurologic signs and symptoms showed an increased threshold and a prolonged CMCT. The data obtained suggest that this technique is useful not only to confirm the neurologic impairment but also to reveal subclinical or pre-symptomatic central motor involvement in BD subjects.