EVALUATION OF CORTICOBULBAR TRACTS AND CR ANIAL NERVES IN CONTROLS AND PATIENTS WITH MULTIPLE-SCLEROSIS BY ELECTROMAGNETIC STIMULATION

The central ans peripheral pathways to muscles innervated by the trige minal, facial and accessory nerve were non-invasively investigated by electromagnetic cortex stimulation. Latencies for facial nerve muscles in controls were similar to those reported in the literature. For the masseter muscle, the total and peripheral latency was 6.9 (SD = 0.6) ms and 2.2 (0.3) ms, respectively. Latencies for evoked responses reco rded from the sternomastoid muscle were 11.0 (SD = 1.0) ms and 4.5 (0. 5) ms. Bilateral muscle responses after cortical stimulation were seen in each of the investigated muscles. In 6 of 10 patients with multipl e sclerosis subclinical deficits could be detected with a prolongation of the total latency up to 20 ms.