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Graph theoretical analysis of functional networks and its relationship to cognitive decline in patients with carotid stenosis.

ABSTRACT: Significant carotid stenosis compromises hemodynamics and impairs cognitive functions. The interplay between these changes and brain connectivity has rarely been investigated. We aimed to discover the changes of functional connectivity and its relation to cognitive decline in carotid stenosis patients. Twenty-seven patients with unilateral carotid stenosis (≥60%) and 20 age- and sex-matched controls underwent neuropsychological tests and resting-state functional magnetic resonance imaging. The patients also received perfusion magnetic resonance imaging. The relationships between cognitive function and functional networks among the patients and controls were evaluated. Graph theory was applied on resting-state functional magnetic resonance imaging network analysis, which revealed that the hemispheres ipsilateral to the stenosis were significantly impaired in "degree" and "global efficiency." The neuropsychological performances were positively correlated with degree, clustering coefficient, local efficiency, and global efficiency, and negatively correlated with characteristic path length, modularity, and small-worldness in the patients, whereas these relationships were not observed in the controls. In this study, we identified the networks that were impaired in the affected hemispheres in patients with carotid stenosis. Specific indices (global efficiency, characteristic path length, and modularity) were highly correlated with neuropsychological performance in our patients. Analysis of brain connectivity may help to elucidate the relationship between hemodynamic impairment and cognitive decline.

SUBMITTER: Chang TY

PROVIDER: S-EPMC4820004 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Graph theoretical analysis of functional networks and its relationship to cognitive decline in patients with carotid stenosis.

Chang Ting-Yu TY Huang Kuo-Lun KL Ho Meng-Yang MY Ho Pei-Shan PS Chang Chien-Hung CH Liu Chi-Hung CH Chang Yeu-Jhy YJ Wong Ho-Fai HF Hsieh I-Chang IC Lee Tsong-Hai TH Liu Ho-Ling HL

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20151001 4

Significant carotid stenosis compromises hemodynamics and impairs cognitive functions. The interplay between these changes and brain connectivity has rarely been investigated. We aimed to discover the changes of functional connectivity and its relation to cognitive decline in carotid stenosis patients. Twenty-seven patients with unilateral carotid stenosis (≥60%) and 20 age- and sex-matched controls underwent neuropsychological tests and resting-state functional magnetic resonance imaging. The p ...[more]

PMID: 26661184

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Dataset Information

Graph theoretical analysis of functional networks and its relationship to cognitive decline in patients with carotid stenosis.

Publications

Graph theoretical analysis of functional networks and its relationship to cognitive decline in patients with carotid stenosis.

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