Comparison Of The Therapeutic Effects And Functional Network Between High And Low Frequency RTMS On Motor Recovery In Stroke Patients

Objective: To compare the therapeutic effects and motor functional network of high frequency and low frequency repetitive transcranial magnetic stimulation(r TMS)on motor functional improvement in ischemic stroke patients by using the resting state functional magnetic resonance imaging(rs-f MRI)and clinical motor functional scales.Methods: Twenty-one patients with subacute ischemic stroke were enrolled in this study and were randomized into two groups: 11 patients in the high-frequency r TMS(HF-r TMS)group and 10 patients in the lowfrequency r TMS(LF-r TMS)group.The HF-r TMS group patients received 10 sessions of 10 Hz r TMS over the ipsilesional primary motor cortex(M1)area and the LF-r TMS group patients received 10 sessions of 1Hz r TMS over the contralesional M1 area.All the patients received the uniform conventional therapy.The rs-f MRI data and Fugel-Meyer assessment scale(FMA),Barthel index(BI)and National Institutes of Health Stroke Scale(NIHSS)were used to assess motor function before and at the end of the last session of r TMS.The independent component analysis(ICA)and seed-based connectivity analysis were used to analyze the resting state motor functional network and the functional connectivities between the network nodes.The differences in motor network,functional connectivity between the network nodes,and the clinical behavioral scales between pre-treatment and post-treatment and between the two groups were calculated.Results: 1.No significant differences in general characteristics and clinical behavioral scales were observed between the two groups before r TMS(P>0.05).Comparing with the baseline,significant improvements in FMA,NIHSS and BI were observed in both groups after 10 days of r TMS treatment(P<0.05).Whereas,no significant differences in the scores of FAM,NIHSS and BI were observed between the two groups after treatment(P>0.05).2:(1)Compared with the baseline,the HF-r TMS group achieved increased functional connectivity(FC)between ipsilesional precentral area,postcentral gyrus,supplementary motor area(SMA)and contralesional postcentral gyrus;the LF-r TMS group achieved increased FC between contralesional precentral area,SMA,middle frontal cortex and ipsilesional SMA.(2)Between the two groups,HF-r TMS group achieved more significant increased FC in bilateral precentral area,SMA,ipsilesional middle frontal cortex and contralateral postcentral gyrus.However,the FC in contralateral middle frontal cortex is lower than the LF-r TMS group.3: The increased FC between the network nodes were as follows:(1)HF-r TMS group: ipsilesional M1 and SMA,contralateral SMA;ipsilesional SMA and M1,PMA,contralateral M1;ipsilesional PMA and SMA,contralateral M1,SMA;contralateral M1 and ipsilesional SMA,PMA;contralateral SMA and ipsilesional M1,PMA.Among them,increased FC of ipsilesional SMA and contralateral SMA,ipsilesional PMA and contralateral M1 were significant(P<0.05).(2)LF-r TMS group: ipsilesional M1 and contralateral SMA,PMA;ipsilesional SMA and contralateral M1,PMA;ipsilesional PMA and contralateral PMA;contralateral M1 and ipsilesional SMA;contralateral PMA and ipsilesional M1,SMA,PMA.(3)Between the two groups: increased FC were found in ipsilesional M1 and SMA of the HF-r TMS group;moreover,the HF-r TMS group achieved more significant increased FC in ipsilesional PMA and contralateral M1,ipsilesional SMA and contralateral SMA compared with the LF-r TMS group.Conclusion: 1.Both high and low frequency r TMS can promote the motor functional rehabilitation for patients with ischemic stroke,but no significant differences between them.2.The recovery of motor function may be related to the increased FC in motor networks after r TMS.3.HFr TMS may better promote the recovery of motor network of ipsilesional hemisphere and the coordination of FC between the ipsilesional and contralateral hemispheries.