Resting-state Functional Magnetic Resonance Imaging In The Treatment Of Transcranial Magnetic Stimulation For Tremor In Parkinson’s Disease

BackgroudParkinson’s disease（PD）is the second neurodegenerative disease which commonly found in middle-aged and elderly people and the incidence rate is about1% in people over 60 years of age.Tremor,as the most typical motor symptom,is commonly treated with dopaminergic drugs.But,with the disease progresses,it’s difficult to control tremor only by drug therapy,which seriously affects the quality of life of patients and brings a huge physical and psychological burden to patients.Transcranial magnetic stimulation（TMS）is a neuromodulation tool that has been widely used in the research and treatment of neurological and psychiatric disorders.However,it’s still unclear that which are the best TMS treatment parameters for PD and their effects on functional brain activity.Resting state functional magnetic resonance imaging,（rf-MRI）can assess the changes of brain spontaneous activity and provide target information and efficacy assessment for TMS therapy.In this study,PD patients with tremor were treated with transcranial magnetic stimulation,and we investigate the tremor-related brain network mechanisms and the effect of TMS on PD patients by functional magnetic resonance imaging.ObjectiveThe aim of this study was to compare f-MRI changes in PD patients with tremor and normal people,we also investigate the effect of TMS on PD patients with tremor and its potential neuromechanism to provide imaging technology support for transcranial magnetic stimulation in Parkinson’s disease.Materials and methods15 tremor-dominant Parkinson’s disease（TD）,30 normal controls（NC）subjects were enrolled.Tremor severity was assessed by the UPDRS.TD patients received TMS for 2 weeks.Patients were scanned using resting state f MRI both preoperatively（PDpre）and 14-day postoperatively（PDpost）,whereas healthy subjects were scanned once.While the regional homogeneity and amplitude low-frequency fluctuation were determined by REST.Then we investigate the tremor-related brain network mechanisms and the effect of TMS on PD patients by functional magnetic resonance imaging.Two independent samples t-test and two paired samples t-test were respectively used to analyze brain area differences and clinical scales between TD and NC groups and before and after treatment in the TD group.Spearman correlation was used to analyze the correlation between changes in functional activity in brain areas and scale scores.ResultsTMS improved the UPDRS III scores in PD patients.In comparison with the NC,TD patient displayed higher Re Ho values in the right precentral gyrus,dorsolateral superior frontal gyrus and precuneus,decreased values in the right triangular inferior frontal gyrus,higher ALLF values in the right inferior cerebellar lobe,left orbital superior frontal gyrus and precuneus,decreased values in the right postcentral gyrus,left nucleus accumbens,superior limbic gyrus and left supplementary motor area.After received 2 weeks therapy,TD patients displayed higher Re Ho values in the left postcentral gyrus and decreased values in the right inferior occipital gyrus,higher ALFF values in the right inferior temporal gyrus and decreased values in the cerebellar vims and and left thalamus.Correlation analysis showed that an increase in ALFF values in the right inferior cerebellar lobe was positively correlated with the total UPDRS III score,and an increase in Re Ho values in the left postcentral gyrus after treatment was positively correlated with a decrease in tremor scores.ConclusionsThis study suggests that the TD tremor network may involve multiple brain regions in the basal ganglia-thalamo-cortical（CTC）and thalamus-cerebellaramo-cortical（STC）.And we we found changes in the default network.After TMS treatment,TD tremor symptoms alleviated and the activity of cerebellar,thalamic,postcentral gyrus and visual cortical areas was altered.