A Study Of Regional Homogeneity Of Resting-state Functional Magnetic Resonance Imaging In Mild Cognitive Impairment

Objective: To investigate the changes of brain function and its relationship with cognitive function in mild cognitive impairment patients by using resting-state Functional Magnetic Resonance Imaging and neurocognitive scales.Methods:Case-control methods were used to collect mild cognitive impairment patients and healthy controls at Wuxi Mental Health Center from April 2018 to October 2018.The neuropsychological test was used to evaluate the cognitive function of the two groups;And then,all subjects received a 3.0 T resting-state Functional Magnetic Resonance Imaging scan.Thirty-two patients with MCI were enrolled(including eighteen males and fourteen females)and Thirty-four normal controls matched(including nineteen males and fifteen females)with age,gender and years of education after removing the head movements and poor image quality.The rs-fMRI data were acquired and preprocessed by DPARSF4.3 software package,calculate the Kendall coefficient consistency of each voxel in the whole brain and its adjacent 26 voxels in the time series to obtain the ReHo.The differences in ReHo values between the two groups were compared,and the correlation between ReHo values and neurocognitive function in MCI patients was analyzed.Results: Compared with the normal controls,there was no significant difference in gender,age,years of education,family status,living ability and current health status between the two groups(P>0.05).However,The scores of ADAS(t = 5.931)and ADAS-Cog(t = 6.181)in MCI group were significantly higher than those in normal group(P<0.01);the scores of numerical breadth(t =-2.008),icon pairing(t =-4.344),verbal analogy(t =-2.040),fast group words(t =-1.842),fast coding(t =-4.229)and picture recall(t =-3.529)were significantly lower than those in normal group(P<0.05,P<0.01).Compared with the normal controls,The ReHo values in the MCI group were significantly lower in the superior temporal gyrus,right middle temporal gyrus,posterior central gyrus,inferior parietal lobule,right angular gyrus and superior marginal gyrus(GRF calibration,Voxel P<0.0214,Cluster P<0.1);And the ReHo values of superior temporal gyrus,right middle temporal gyrus,posterior central gyrus,inferior parietal lobule,right angular gyrus and superior marginal gyrus were positively correlated with ADAS-Cog scale score(r = 0.393),negatively correlated with icon pairing(r = 0.045),fast coding(r = 0.047)and connection test(r = 0.029)in the MCI group(P<0.05).Conclusion: 1.The cognitive impairment of MCI patients is manifested in short-term memory,working memory,associative learning,learning strategies,knowledge breadth,processing speed,concentration of attention,speech understanding,verbal reasoning,verbal fluency,verbal expression,visual-motor coordination,free recall and object naming.2.Spontaneous neuronal activity in superior temporal gyrus,right middle temporal gyrus,posterior central gyrus,inferior parietal lobule,right angular gyrus and superior marginal gyrus was abnormal in MCI patients.3.ReHo values of superior temporal gyrus,right middle temporal gyrus,posterior central gyrus,inferior parietal lobule,right angular gyrus and superior marginal gyrus in MCI patients were correlated with ADAS-Cog,icon pairing,fast coding and connectivity test scores,it is suggested that cognitive dysfunction in patients with MCI may be related to abnormal spontaneous neurological activity in the above brain regions.