Ischemic Stroke in Pontine and Corona Radiata: Location Specific Impairment of Neural Network Investigated With Resting State fMRI.

Chunxiang Jiang,Chunxiang Jiang,Chunxiang Jiang,Siqi Cai,Siqi Cai,Li Yi,Lijuan Zhang,Lijuan Zhang

doi:10.3389/fneur.2019.00575

Abstract

Objective: This study aims to investigate location-specific functional remodeling following ischemic stroke in pons and corona radiata.Methods: This study was approved by the local Institutional Review Board. Written consent was obtained from each of the participants prior to the MRI examination. Thirty six subjects with first ever acute ischemic stroke in pons (PS, n = 15, aged 62.8 ± 11.01 years) or corona radiata (CRS, n = 21, aged 59.33 ± 13.84 years) as well as 30 age and sex matched healthy controls (HC, n = 30, aged 60 ± 6.43 years) were examined with resting state functional magnetic resonance imaging (rs-fMRI). Regional homogeneity (ReHo) and degree centrality (DC) were calculated using a voxel-based approach. Intergroup differences in ReHo and DC were explored using a permutation test with a threshold-free cluster enhancement (PT TFCE, number of permutations = 1,000, family-wise error rate (FWER) < 0.05).Results: ReHo and DC alterations were identified in distributed anatomies for both PS and CRS groups. DC mainly increased in the bilateral anterior and posterior cingulate cortex, the inferior frontal-orbital gyrus, and decreased in the bilateral cuneus, calcarine, and the precuneus, while ReHo mainly decreased in the precentral and the postcentral gyri, inferior parietal lobules, precuneus, posterior cingulate cortex, and the superior occipital gyrus. PS and CRS groups were not significantly different in ReHo or DC (FWER > 0.05).Conclusions: Focal ischemic stroke in pons or corona radiata leads to extensive alterations in the functional network centrality. IS-induced network remodeling is more anatomy-specific than pathway-specific, which may underpin the clinicotopographical profiles during the disease dynamic. Approaches targeting neural pathway and functional connectivity may shed light on a better characterization and management innovation of ischemic stroke.

Highlights

Despite progress in the disease management and new drug development, the mortality of ischemic stroke (IS) remains high
This study examined the differences in the intrinsic neural activity and connectivity pattern of the whole-brain functional networks in patients with pontine and corona radiata IS with voxelwised Regional homogeneity (ReHo) and degree centrality (DC) approaches
Pons and corona radiata are located in the same projection between the cortex and the brain stem, but they involve the nodal elements of the sensory-motor circuit at a different level

Summary

Introduction

Despite progress in the disease management and new drug development, the mortality of ischemic stroke (IS) remains high. In addition to the disruption to the vascular supply, cerebral ischemia induces extensive structural and functional damages with complex pathophysiological mechanisms [2]. Studies with an unspecified IS location may be confounded by the heterogeneity of the functional specification [3,4,5]. Lesion inference analysis revealed that the functional outcome of IS corresponds to brain areas and vascular territory with causal attributions to the behavioral and cognitive consequences [6, 7]. The functional impairment associated with IS in different anatomies varies among individuals [8, 9], but may induce a similar clinical profile. The functional reorganization of the brain with IS and the overall outcome may be associated with the lesion location across subjects with IS.

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Discussion

Conclusion