Alterations of brain network topology and structural-functional connectivity coupling in capsular versus pontine stroke.

BACKGROUND AND PURPOSE: This study was conducted to investigate whether capsular stroke (CS) and pontine stroke (PS) have different topological alterations of structural connectivity (SC), functional connectivity (FC) and the SC-FC coupling correlation with the movement assessment scores.

METHODS: Resting-state functional magnetic resonance imaging (rs-fMRI) and diffusion tensor imaging (DTI) were prospectively acquired in 46 CS, 36 PS, and 29 healthy controls (HCs). Graph theoretical network analyses of SC and FC were performed. Patients with lesions in left and right were analyzed respectively.

RESULTS: For the FC, the PS and CS both showed higher local efficiency (Eloc) than the HCs and the CS also showed higher clustering coefficient (Cp) than the HCs in the right-lesion analysis. For the SC, the PS and CS both displayed different normalized clustering coefficient (γ), small-worldness (σ), characteristic path length (Lp) with the HCs. Additionally, the CS showed higher normalized characteristic path length (λ) and lower Cp than the HCs and PS showed higher λ and lower global efficiency (Eg) than the HCs in the right-lesion analysis. Whereas, γ, σ, Cp, Lp were only significant between the PS and CS in the right-lesion analysis. Importantly, CS had a weaker coupling than the PS and the HCs in the right-lesion analysis. In addition, the patients had weaker structural-functional connectome correlation than controls.

CONCLUSIONS: CS and PS both showed FC and SC disruption and the CS had a weaker coupling than the PS in the right lesion analysis. This may provide useful information for individualized rehabilitative strategies.