Alterations of Regional Homogeneity in Parkinson's Disease: A Resting-State Functional Magnetic Resonance Imaging (fMRI) Study.

Objective The objective of this study is to investigate the regional homogeneity (ReHo) of spontaneous brain activities in Parkinson's disease (PD) patients. Methods In total, 20 PD patients and 20 matched normal controls (NCs) participants were recruited for this study. The regional homogeneity (ReHo) approach based on resting-state functional magnetic resonance imaging on a 3T MRI system was used to investigate local brain activity. We examined activity in two frequency bands, slow-4 (0.027-0.073 Hz) and slow-5 (0.010-0.027 Hz). Two-sample t-tests were used to determine the between-group differences in the ReHo data. Pearson correlation analysis was used to explore the relationships between the ReHo values and clinical indices in PD patients. Results Compared with NCs, PD patients showed decreased ReHo values in the right middle occipital gyrus, right cuneus, and left superior occipital gyrus, and increased ReHo values in the right middle frontal gyrus in slow-4. PD patients showed decreased ReHo values in the right calcarine, left calcarine, and right precentral gyrus compared with NCs in slow-5. Correlation analysis showed that disease duration was negatively correlated with ReHo values in the right precentral gyrus in PD patients. Conclusions These results indicate that several brain regions were altered in PD patients. The regions are associated with the visual network-related cortex, motor cortex, and default mode network. The findings provide new insights into the neuropathophysiology of PD.