Multimodal Imaging Study On Motor Rehabilitation Of Acute Ischemic Stroke Patients

Part OneFast Diffusion Kurtosis Imaging in Patients of Acute Ischemic Stroke:A Longitudinal StudyPurpose:To observe the changes of DKI parameters such as MK,MD and FA with time and its correlation with clinical prognosis in patients with acute ischemic stroke using fast diffusion kurtosis imaging.Methods:In this study,21 patients with acute ischemic stroke were enrolled.These patients were followed up for 4 times(1week,2weeks,3months and 6months after the onset)with scanned by DKII magnetic resonance examination,and the clinical scores were measured.Obtain DKI parameters such as MK,MD,FA,as well as the lesion volume of the MK and MD map.Calculate the percentage change of each parameter,MD/MK mismatch and FA asymmetry,and to explore its relevance to clinical scoring.Results:We found regular time-signal curves of DKI parameters of MK,MD and FA in infarcted lesions through the longitudinal observation.There were significant differences in the parameters of the lesion at each time point compared with the normal contralateral.There was no significant difference in MD/MK area during one week of onset.The rate of change of MK,MD and FAasy in 3 months was positively correlated with the clinical score at 3 months of onset.Conclusion:The time-signal curve of fast DKI parameters change dynamically with the course of disease,and has certain regularity.DKI may be used to predict the extent of ischemic cerebral infarction in early stage.Fast DKI may help to predict the clinical outcome of stroke patients.Part TwoRepetitive Transcranial Magnetic Stimulation combined with Resting-State Functional Magnetic Resonance Imaging in the Rehabilitation of Acute Ischemic Stroke PatientsPurpose:To investigate the changes of cortex functional connectivity in stroke patients before and after high frequency rTMS treatment with resting-state magnetic resonance imaging,and to provide the evidence for brain functional reorganization and rehabilitation after rTMS treatment.Methods:Thirty-one patients with acute ischemic stroke were randomly divided into rTMS group and control group.The resting state magnetic resonance imaging and clinical function scores were performed before and after high frequency repetitive transcranial magnetic stimulation treatment and 3 months after onset.By comparing the changes of functional connectivity in bilateral M1 region of the patients and the functional connection between the primary motor cortex and the whole brain,the differences between the patients before and after treatment were found with the blank control group.Results:The clinical scores of rTMS treatment group were improved after treatment and 3months after onset,which was statistically significant.However,there was no significant difference in the functional connectivity value of bilateral M1 between the two groups at each time point;repeated measurement analysis also showed no group*time interaction effect.But the mixed model analysis showed that there was a main effect between groups before and after treatment:compared to the sham group,the treatment group showed higher functional connectivity between ipsilesional M]with ipsilesional middle frontal lobe,contralesional posterior central gyrus,brodmann40,precuneus,cingulate gyrus,paracentral lobule,brodmann 5/7 area,IPL,insula,caudate nucleus and lentiform nucleus;but lower functional connectivity with contralesional cerebellum,occipital lobe,temporal gyrus,hippocampus and parahippocampal gyrus.And the interaction with group*time different brain regions were contralesional cerebellar hemisphere,posterior central gyrus,IPL,supramarginal gyrus.And the above differences were still partly observed after 3 months of onset,while the interaction with group*time different brain regions changed to be the contralesional insula,superior temporal gyrus and lingual gyrus.Conclusion:rTMS may help promote poststroke motor recovery.Noninvasive fMRI technique can observe the motor function reorganization changes before and after rTMS treatment,which was helpful to understand the mechanism of repeated transcranial magnetic stimulation.In conclusion,rTMS may be a promising and safe method for rehabilitation of stroke patients.