Relationship between Small-world Network and Cognitive Impairment for Patients with White Matter Lesions Based On Diffusion Tensor Imaging / 中国康复理论与实践

Objective:To explore the relationship between small-worldness of brain network and cognitive impairment in patients with white matter lesions (WMLs) based on diffusion tensor imaging (DTI). Methods:From January, 2016 to December, 2017, 46 WMLs patients and 36 controls matched genders, ages and education levels from Beijing Tiantan Hospital were screened with DTI. The patients were divided into vascular cognitive impairment non-dementia (VCIND) and vascular dementia (VaD) groups according to the results of cognitive assessments. The brain structure network was created based on DTI data, and the topological properties of the whole-brain small-world network were calculated, and the correlation between the small-worldness and the severity of cognitive impairment was analyzed. Results:The global efficiency, local efficiency, shortest path length and clustering coefficient were different between the patients and the controls (F > 3.252, P < 0.05), as well as the properties of the small-world network, λ, γ and σ (F > 7.378, P < 0.01). The λ, γ and σ were correlated with the total score of Montreal Cognitive Assessment (|r| > 0.402, P < 0.05). Conclusion:The brain structure network is small-world network for patients with WMLs, and the decrease of small-world properties may relate to the cognitive impairment.

Resting-state Neural Networks and Granger Causal Connectivity for Patients with Cognitive Impairment Associated with Leukoaraiosis / 中国康复理论与实践

Objective:To compare the difference in resting state networks among leukoaraiosis (LA) patients with or without mild cognitive impairment, and healthy controls, as well as the functional connectivity under Granger causality analysis (GCA). Methods:Subjects aged 40 to 80 years, including 34 LA-MCI patients, 15 LA patients with normal cognition and 33 healthy controls, accepted resting-state functional magnetic resonance imaging. Independent component analysis was used to separate functional brain networks, and difference of activation was determined with two sample t-test. GCA was used to analyze effective connectivity of these functional networks. Results:Eight resting state networks were obtained, including default mode network, motor network, medial visual network, lateral visual network, right-memory network, left-memory network, auditory network and executive network. Activation was different among three groups. Effective connectivity of RSNs was also different among three groups. Conclusion:Components of the resting state networks keep changing as LA progressing. Activation decreases as patients' cognition impaired. The direction and strength of connections remodel.

Impact of Cholinergic Pathway Damage on Cognitive Impairment Caused by Cerebral White Matter Lesions / 中国康复理论与实践

Objective To investigate the relationship between cholinergic pathway damage and the executive dysfunction of patients with different degrees of cognitive impairment caused by cerebral white matter lesions(WML). Methods From March,2016 to December,2017,115 patients were recruited,whose characteristics,such as age,gender, education,and history of hypertension,diabetes and stroke were recorded.According to the T2-weighted MRI,80 patients were defined as WML.WML patients were divided into cognitively normal(CN)group(n=41),vascular cognitive impairment of none dementia(VCIND)group(n=21)and vascular dementia(VaD)group(n=18)ac-cording to the result of Montreal Cognitive Assessment(MoCA)and Clinical Dementia Rating(CDR).Other 35 cases without WML and cognitive impairment were as control group.WML under MRI were evaluated with Cho-linergic Pathways Hyperintensities Scale(CHIPS).All the WML patients were assessed with Stroop Color-Word Test,Trail Making Test, Symbol Digital Modalities Test, and Verbal Fluence Test.The correlation between the scores of CHIPS and the executive tests were analysed. Results There was no significant difference in age, gender, level of education, and cardiovascular disease risk factors among four groups(P>0.05),but there were significant differences in scores of MoCA and CHIPS(F>25.781,P<0.001),while the score of MoCA was the least(P<0.01)and the scores of CHIPS were the most in VaD group (P<0.001).The CHIPS scores of left and bilateral hemisphere negatively correlated with all the scores of execu-tive tests(P<0.05),while that of the right hemisphere just correlated with the scores of some executive tests(P<0.05). Conclusion For cognitive impairment after WML,cholinergic pathway damage may relate with the executive function impairment,especially the damage in left cerebral hemisphere.