Magnetic stimulation and movement-related cortical activity for acute stroke with hemiparesis

Background and purpose: This double-blind, randomized, placebo-controlled study investigated the beneficial effects of repetitive transcranial magnetic stimulation (rTMS) to patients with motor paresis in acute subcortical stroke on functional recovery and electrophysiological measures. Methods: Twenty patients with acute stroke were randomized into real rTMS (n=10) or sham (n=10) groups. Patients received five daily sessions of rTMS with 1200 pulses at 1Hz for 20min or sham stimulation over the contralesional motor cortex. Movement-related cortical potential MRCP, consisting of the Bereitschaftpotential, negative slope (NS) and motor potential (MP), was recorded during self-paced wrist extension of the affected limb associated with assessment of the Fugl-Meyer assessment (FMA) of the upper extremity, the pegboard test and the grip strength before and after the rTMS session. Results: Real rTMS improved the FMA and pegboard test scores compared to the sham group in the affected hand. This improvement was associated with increases in the MP and NS over the front-central sites in the ipsilesional hemisphere, whereas the sham group did not show significant changes in MRCP components by rTMS. Conclusions: Our findings suggest that low-frequency rTMS to the contralesional motor cortex facilitates functional recovery of paretic limbs in acute stroke patients through enhancing the the neuronal activity of ipsilesional motor and pre-motor areas.