Magnetic Resonance Imaging Studies On Structural And Functional Abnormalities Of The Caudate In Depression With Parkinson’s Disease

Purpose: Depression is a common non-motor symptom of Parkinson’s disease(PD).Its pathogenesis is not clear.During the onset of PD,the caudate is vulnerable for the deposition of iron and Lewy bodies.Caudate is a key structure of emotional generation and regulation.Therefore,the relationship between the structural and functional abnormalities of the caudate nucleus and the pathogenesis of depression with Parkinson’s disease(DPD)is a hot spot.This experiment attended to observe the changes of structural and functional connectivity of bilateral caudate nucleus in DPD.Materials and Methods: Forty-three PD patients(including twenty-one DPD)and twenty-three age,gender and educational level matched healthy controls(HC)were included in this study.Resting state functional Magnetic resonance imaging(rs-f MRI)and structural MRI data was acquired.The resting-state brain activity was measured by functional connectivity(FC)method and the gray matter(GM)volume was attained by the voxel-based morphology(VBM)analysis.And we selected bilateral caudate nucleus as the region of interest.Two-sample t test was then performed to detect the group differences with gender,age,educational level as covariates.Results: The bilateral caudate’s volume did not show any difference among the three groups.In terms of FC,we discovered the significant difference among the three groups.Compared to the NDPD patients,the DPD patients exhibited increased left caudate FC with the left precuneu,left superior parietal lobule and increased right caudate FC with the left middle occipital gyrus,right lingual gyrus,right posterior cingulate,left cuneus.Compared to the HCs,DPD patients exhibited increased left caudate FC with the left precuneus.Increased right caudate FC with the left middle occipital gyrus,right lingual gyrus was also observed in the DPD group.Compared to the HCs,NDPD patients exhibited increased left caudate FC with the left precentral gyrus and decreased left caudate FC with the left superior frontal gyrus,left medial frontal gyrus,left superior parietal lobule.Conclusion: Although there was no explicitly abnormal change in bilateral caudate nucleus’ volume among the three groups,but we detected the imbalanced FC between the caudate nucleus and the default mode network,visual processing network in DPD.Besides,we also found the dysfunction of the cortex-basal ganglia motor loop in nondepression with Parkinson’s disease.