Regional Homogeneity Changes In Patients With Parkinson's Disease

Background:Parkinson's disease(PD)is the most common neurodegenerative movement disorder,affecting about 1%of people aged 65 or older worldwide.Resting state brain activity in Parkinson's disease(PD)can give clues to the pathophysiology of the disorder,and might be helpful in diagnosis.In the current study,we used a regional homogeneity(ReHo)method to investigate PD-related modulations of neural activity in the resting state and abnormal neural circuits.And to explore the effects of levodopa on brain function at different time points.Methods:We acquired FMRI data in 45 patients with PD at before and after levodopa administration,as well as in 45 age-and sex-matched normal controls.Using the method of ReHo,to explore how the brain function changes in different brain regions with L-dopa intake.The correlations of the VPM and right Calcarine ReHo with bradykinesia improvement were statistically analyzed.Results:Compared with NC group,PD-off-medicine group have significantly decreased ReHo values in the bilateral Olfactory,Frontal_sup_orb_L and ventral posterior medial nucleus_R;and increased areas in the STN_R,bilateral Caudate body,SMA L,bilateral Frontal Mid and Precuneus R.Compared with T1 group,T2 group had increased ReHo values in the Para Hippocampal_L and ventral posterior medial nucleus_R;and decreased ReHo values in the bilateral Frontal superior medial and left Frontal.Compared with T1 group,T3 group have significantly decreased ReHo values in the Prefrontal cortex bilateral Frontal_Mid,bilateral Angular and Frontal_med_orb_R;increased ReHo values in the Precentral_L,PMC_L and ventral posterior lateral nucleus_L.The ReHo of the right VPM is positively correlated with the bradykinesia improvement,but right calcarine is negatively correlated with the bradykinesia improvement.Conclusions:Our findings demonstrate that changes of ReHo value in PD patients are extensive.L-dopa may normalize aberrant functional patterns in PD.After intake L-Dopa,in some brain regions,ReHo value change regularly with time.The ventral posteromedial nucleus of the thalamus can be used as a potential target for deep brain stimulation in patients with PD whose main clinical manifestation is bradykinesia.