Lesion-based structural and functional networks in patients with step length asymmetry after stroke

Abstract

Objective: The aim of this study was to determine common structural and functional networks associated with asymmetric step length after unilateral ischemic stroke.

Methods: Thirty-nine chronic stroke patients were divided into two groups, based on the presence or absence of asymmetric step length. In each group, each lesion was mapped onto a brain magnetic resonance image. The structural and functional networks of brain regions connected to each lesion were identified using a public diffusion tensor and resting state function magnetic resonance image dataset. To identify brain regions associated with asymmetric step length, we conducted voxel-wise independent sample t-tests for structural and function lesion network maps.

Results: At least 85% of lesions showed functional network overlap in the bilateral frontal lobe. Functional connectivity of the dorsolateral prefrontal cortex in the contralesional hemisphere was significantly decreased in group 1 compared to that in group 2.

Conclusions: The dorsolateral prefrontal cortex may have an important role in compensating for an asymmetric step length after a unilateral stroke.