Diffusion tensor imaging to determine the potential motor network connectivity between the involved and non-involved hemispheres in stroke

Abstract

Abstract. Hemiparetic stroke is a common motor network disorder that affects a wide range of functional movements due to cortical and subcortical network lesions in stroke patients. Conventional magnetic resonance imaging (MRI) has been used to examine structural brain damage, but the integrity and connectivity of the whole brain are poorly understood. Hence, advanced neuroimaging with diffusion tensor imaging (DTI) has been developed to better localize fiber architecture and connectivity in the motor network or pathways that are responsible for motor impairments in hemiparetic stroke. To ascertain motor network connectivity between the involved and non-involved hemispheres in stroke patients, we analyzed the DTI data from all right hemiparetic stroke patients using fractional anisotropy (FA) and network parameters, including node degree and edge betweenness centrality (EBC). The FA values were substantially lower in the left hemisphere than the right hemisphere. Similarly, the node degree and EBC were significantly lower in the left hemisphere than the right hemisphere. The present brain network analysis may provide a useful neuropathway marker for accurate diagnosis and therapeutic intervention.

Structural brain networks and functional motor outcome after stroke—a prospective cohort study

“…In humans, severity of aphasia has been linked to disruption of structural hubs in a language network (Gleichgerrcht et al , 2015 b ), apathy and post-stroke depression have been found to be related to reduced local and global efficiency in distributed sub-networks. Structurally, reduced centrality measures in stroke hemispheres ( Lee et al , 2015 ), as well as reduced communicability ( Crofts et al , 2011 ) and a modified backbone structure in contralesional hemispheres have been described. In a different cohort, nodal centrality measures of the inferior parietal lobe and the posterior cingulate gyrus were associated with motor impairment on the FM scale and immediate recall, respectively ( Zhang et al , 2017 ).…”

Early effect of thrombolysis on structural brain network organisation after anterior‐circulation stroke in the randomized WAKE‐UP trial

“…Smaller integration and higher segregation parameters as well as changes in central network hubs as a result of focal brain damage have previously been described in animal studies using high‐resolution tensor imaging and network simulations (Sinke et al, 2018; Straathof et al, 2019). In addition to reduced measures of centrality in stroke hemispheres (Lee et al, 2015), structural network studies have also revealed changes in the contralateral hemisphere, such as reduced communicability (Crofts et al, 2011) and altered backbone structure(van den Heuvel et al, 2012), after stroke.…”