RT Journal Article
SR Electronic
T1 Conduction deficits of callosal fibres in early multiple sclerosis
JF Journal of Neurology, Neurosurgery & Psychiatry
JO J Neurol Neurosurg Psychiatry
FD BMJ Publishing Group Ltd
SP 633
OP 638
DO 10.1136/jnnp.68.5.633
VO 68
IS 5
A1 Klaus Schmierer
A1 Ludwig Niehaus
A1 Simone Röricht
A1 Bernd-Ulrich Meyer
YR 2000
UL http://jnnp.bmj.com/content/68/5/633.abstract
AB OBJECTIVE To study the diagnostic usefulness of transcallosal inhibition (TI) elicited by transcranial magnetic stimulation (TMS) in detecting central conduction deficits in early multiple sclerosis. Corticospinally mediated excitatory responses evoked by TMS are accepted as a sensitive diagnostic tool in multiple sclerosis. Recently, TI evoked by TMS has been introduced as a new paradigm to test the function of callosal fibres interconnecting both hand associated motor cortices. METHODS Focal TMS of the motor cortex was performed in 50 patients with early relapsing-remitting multiple sclerosis. Corticospinally mediated (central motor latencies, amplitudes) and transcallosally mediated (onset latency and duration of TI) stimulation effects were investigated. RESULTS TMS disclosed abnormalities of corticospinally mediated responses in 62% and of TI in 80% of the patients. CONCLUSION The assessment of TI allows the discovery of lesions within the periventricular white matter that were not accessible by neurophysiological techniques before. This new paradigm increases the sensitivity of TMS with which to detect central conduction deficits in early multiple sclerosis.