Resting-state Functional Magnetic Resonance Imaging Of Multiple System Atrophy

Part ?:Abnormal regional homogeneity in multiple system atrophy with different subtypes:a study of resting-state functional magnetic resonance imagingObjective:To investigate the changing of regional homogeneity(ReHo)and its relationship with the severity of the symptom in multiple system atrophy patients with different subtypes using resting-state functional magnetic resonance imaging(rs-fMRI)technology.Method:A total of 48 multiple system atrophy(MSA)patients(including 25 MSA-C patients and 18 MSA-P patients)and 25 well-matched healthy controls were scanned with rs-fMRI for ReHo analysis,The Mini Mental State Examination(MMSE)?Montreal Cognitive Assessment(MoCA)?and Unified Multiple System Atrophy Rating Scale(UMSARS)were performed to assess the clinical symptom.And then,exploring the relationship between the changes of ReHo values and severity of clinical symptoms.Result:Compared with the controls,the MSA-C patients showed higher ReHo in bilateral precuneus gyrus,left hippocampal gyrus,left middle occipital gyrus,and Cerebelum Vermis ?-?,but lower in left cerebellum anterior and posterior lobe;The MS A-P patients had increased ReHo in bilateral thalamus,left caudate,brainstem,and cerebellum vermis ?-?,but decreased ReHo in left cerebellum anterior and posterior lobe;Compared with the MSA-P patients,the MSA-C patients had significantly increased ReHo in areas including left precuneus gyrus,left hippocampal gyrus,left middle temporal gyrus,as well as decreased ReHo in right middle occipital gyrus.Significant correlation between ReHo and MoCA?UMSARS-II scores was respectively found in bilateral precuneus gyrus and bilateral thalamus in MSA-C and MSA-P patients.Conclusion:Abnormal brain activity of MSA might exist by resting-state fMRI.These functional changes suggest that the abnormal synchrony of brain regional functional activity probably plays an important role in pathophysiology.Part ?:Abnormalities of interhemispheric synchrony differentiate the Parkinson variant of MSA from PDObjective:To investigate the resting-state functional connectivity of the two hemispheres between the Parkinsonian type of multiple system atrophy(MSA-P)and Parkinson's disease(PD).Methods:A total of 25 MSA-P,29 PD patients and 29 well-matched healthy controls were scanned with resting-state functional magnetic resonance imaging(rs-fMRI)for voxel mirrored homotopic correlation(VMHC)analysis.The Mini Mental State Examination(MMSE),Montreal Cognitive Assessment(MoCA),Frontal Assessment Battery(FAB)and Unified Parkinson's Disease Rating Scale-?(UPDRS-?)were performed to assess the clinical symptom.Then the relationship between the change of VMHC values and severity of clinical symptoms was investigated.Results:Compared with healthy controls,MSA-P and PD patients both showed decreased VMHC in bilateral cerebellum posterior lobe,precuneus gyrus,middle temporal gyrus,and postcentral gyrus.Compared with PD or healthy controls,MSA-P patients exhibited lower VMHC in bilateral putamen.Significant negative correlation between VMHC values of putamen and UPDRS-? scores was found in MSA-P patients.Conclusion:These functional changes suggest that the abnormal interhemispheric synchrony probably plays an important role in pathophysiology of both MSA-P and PD,and abnormal VMHC values in putamen of MSA-P may be helpful in differentiating MSA-P from PD.