Effect Of High Frequency Repetitive Transcranial Magnetic Stimulation On Motor Dysfunction After Ischemic Stroke:an FMRI Study

Objective: To investigate the efficacy of repetitive transcranial magnetic stimulation(rTMS)on motor recovery related functional network in patients with ischemic stroke by using the resting state functional magnetic resonance imaging(rs-fMRI)and clinical motor functional scales.Methods: 22 identified patients with middle cerebral artery(MCA)ischemic stroke were randomized into two groups: 11 patients in the real stimulation group(rTMS group)and the other 11 patients in the sham stimulation group(Sham group).The rTMS group received a 10-day-session high-frequency rTMS(10Hz,90% of resting motor threshold)treatment over primary motor cortex(M1)of the affected hemisphere,the Sham group received the sham rTMS with the same noise and duration.The treatment sessions and the other conventional therapies of the two groups are uniform.The rs-fMRI data and clinic scale scores of the two groups were collected respectively at the baseline and after the treatment.The motor related resting state functional brain network and their relevance were analyzed by using the independent component analysis(ICA)and delay relevant methods.The statistical differences inter-and intra-the two groups were calculated.Results:(1)Compared with baseline,the scores of FAM,NIHSS and BI of both groups improved significantly after the treatment.Compared with the Sham group,the patients of rTMS group gained a more significant improvement in FMA and BI test,however,there were no significantdifferences between two groups in the NIHSS.(2)motor network,cerebellum network,control-execution network,the right side of the frontal-partial network and salience network were elected in this study.Compared to the baseline,the functional connectivity of the rTMS group,which between supplementary motor area(SMA)on both sides and precentral gyrus of affected side were improved after rTMS treatment.In addition,the rTMS group and Sham group gained significant differences in the functional connectivity of ipsilesional posterior central gyrus,the contralesional cerebellar and right side of the parietal lobe.(3)the correlation of motor network with several other motor-related network were increased after rTMS treatment.Conclusion : High frequency rTMS stimulate over contralesional M1 could improve the motor function of ischemic stroke patients,and the improvement of the clinical effect may be associated with rTMS which can improve motor functional related network connectivity and promote the capacity of information integration of motor related network.