title: Disruption of brain connectivity in acute stroke patients with early impairment in consciousness.
abstract: Impairment in consciousness is common in acute stroke patients and is correlated with the clinical outcome after stroke. The underlying mechanism is not completely understood, with little known about brain activity and connectivity changes in acute stroke patients having impaired consciousness. In this study, we investigated changes in regional brain activity and brain networks of consciousness impaired stroke patients, as well as the amplitude of spontaneous low frequency fluctuation (ALFF) of each time series. Regional homogeneity (ReHo) of each voxel was measured, and resting state network analysis was consequently conducted. Results from this study demonstrate that, compared to normal subjects, the intensities of ALFF and ReHo, as well as the strength of the default mode network (DMN) connectivity, were significantly decreased in the precuneus and posterior cingulate cortex regions among stroke patients with impaired consciousness. Furthermore, the strength of the DMN was highly correlated with differences in the Glasgow Coma Scale (GCS) scores between the onset time and the scanning time. Results from this study suggest that the resting state fMRI is a feasible tool for the evaluation of acute stroke patients with an early impairment of consciousness. The detailed mechanisms, implications of these brain activities and networks exhibiting changes will require further investigation.
authors.affiliation: Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University Taipei, Taiwan ; Department of Diagnostic Radiology, Chang Gung Memorial Hospital at Chiayi, College of Medicine and School of Medical Technology, Chang-Gung University Taoyuan, Taiwan.
authors.forename: Yuan-Hsiung
authors.initials: YH
authors.lastname: Tsai
authors.affiliation: Department of Biomedical Engineering, New Jersey Institute of Technology Newark, NJ, USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Yuan
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital at Chiayi, College of Medicine and School of Medical Technology, Chang-Gung University Taoyuan, Taiwan.
authors.forename: Yen-Chu
authors.initials: YC
authors.lastname: Huang
authors.affiliation: Department of Diagnostic Radiology, Chang Gung Memorial Hospital at Chiayi, College of Medicine and School of Medical Technology, Chang-Gung University Taoyuan, Taiwan.
authors.forename: Mei-Yu
authors.initials: MY
authors.lastname: Yeh
authors.affiliation: Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University Taipei, Taiwan ; Institute of Neuroscience, National Yang-Ming University Taipei, Taiwan.
authors.forename: Ching-Po
authors.initials: CP
authors.lastname: Lin
authors.affiliation: Department of Biomedical Engineering, New Jersey Institute of Technology Newark, NJ, USA.
authors.forename: Bharat B
authors.initials: BB
authors.lastname: Biswal
keywords: brain connectivity; fMRI; resting state; resting state functional connectivity; stroke