Altered Brain Network Centrality In Patients With Mild Cognitive Impairment:An FMRI Study Using A Voxel-wise Degree Centrality Approach

Objective: Previous studies in patients with Alzheimer’s disease(AD)have shown amyloid beta(Aβ)accumulation in the brain and abnormal brain activity,with mild cognitive impairment(MCI)in early stages of the disease.The aim of the current study was to investigate functional connectivity in patients with MCI,in order to have a deeper understanding of the pathological and physiological mechanisms of MCI patients,and to provide possible theoretical support for early diagnosis and early clinical intervention in patients with AD,so as to leave sufficient time for the prevention and treatment of AD.Methods: A total of 24 subjects were recruited in the First Affiliated Hospital of Nanchang University,including 12 patients with Mild Cognitive Impairment(MCIS)(including 6 males and 6 females)and 12 Healthy controls(HC)(including 6males and 6 females).Matched for age,gender and lifestyle factors.All subjects were first evaluated clinically,including course of disease,systolic blood pressure,diastolic blood pressure,heart rate,daily living ability scale,simple mental status check scale(MMSE),central nervous specific protein(S100-β protein),etc.Then Siemens 3.0T MRI was used to acquire conventional magnetic resonance(c MRI),high-resolution T1 thin-layer structure image,and resting-state functional image(rs-f MRI),etc.Rs-f MRI images were preprocessed by corresponding software to obtain the brain network degree centrality(DC)value.Finally,the abnormal DC values of the brain regions between the MCIS group and the HCS group were obtained through statistical analysis,which was used to evaluate the changes in the strength of brain network connection,and to analyze the correlation between the abnormal DC values of the brain regions and general clinical data.Results:(1)Compared with HCS,MCIS showed decreased DC values in the left inferior temporal gyrus(ITGL),while significantly increased DC values in the right fusiform gyrus and the left accessory motor area(SMA).(2)Compared with HCS,The DC value of ITGL was negatively correlated with the disease course of MCI patients,but positively correlated with the Mini-mental State Examination(MMSE)score of MCI patients.Conclusions: In MCIs,there was abnormal central strength of brain network degree at the voxel level in several brain regions,and the DC value of ITGL was negatively correlated with the course of disease and positively correlated with the simple mental state examination(MMSE)score,suggesting that this may reflect the pathological process of AD development,which is of great significance for the early diagnosis and early clinical intervention of AD.