Use of transcranial magnetic stimulation with measurement of motor evoked potentials in the acute period of hemispheric ischemic stroke.

Abstract

Functional derangements in the brain during the acute period of ischemic hemispheric stroke (IS) were assessed in terms of the severity of the motor neurological deficit in the acute period of IS and neurophysiological measures of motor evoked potentials (MEP) using transcranial magnetic stimulation (TCMS). A total of 52 patients (23 women, 29 men, mean age 58.5 +/- 8.7 years) were studied. Patients were divided into two subgroups: group 1 consisted of 29 patients with good functional outcomes from the acute period; group 2 consisted of 23 patients with poor functional outcomes. The use of TCMS for recording MEP demonstrated increases in the latency of the M response both after stimulation of the projection of the motor area of the cortex of the lesioned hemisphere and after stimulation of the spinal cord. There were increases in the central motor conduction time (CMCT) in the lesioned hemisphere of the brain and a negative correlation was seen between the severity of the neurological defect and CMCT on the one hand (r = -0.65 to -0.78; p < 0.001) and, on the other, the latency of the M response in TCMS of the motor zone of the cortex on the side of the hemispheric stroke (r = -0.65 to -0.79; p < 0.001). The increases in the latency of the M response and CMCT have prognostic significance for early assessment of the outcome of IS.