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

Abstract

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) and functional connectivity (FC), as well as correlations of SC‐FC coupling with movement assessment scores. Methods Resting‐state functional magnetic resonance imaging and diffusion tensor imaging were prospectively acquired in 46 patients with CS, 36 with PS, and 29 healthy controls (HCs). Graph theoretical network analyses of SC and FC were performed. Patients with left and right lesions were analyzed separately. Results With regard to FC, the PS and CS groups both showed higher local efficiency than the HCs, and the CS group also had a higher clustering coefficient (Cp) than the HCs in the right lesion analysis. With regard to SC, the PS and CS groups both showed different normalized clustering coefficient (γ), small‐worldness (σ), and characteristic path length (Lp) compared with the HC group. Additionally, the CS group showed higher normalized characteristic path length (λ) and a lower Cp than the HCs and the PS group showed higher λ and lower global efficiency than the HCs in the right‐lesion analysis. However, γ, σ, Cp and Lp were only significantly different in the PS and CS groups compared with the HC group in the right‐lesion analysis. Importantly, the CS group was found to have a weaker SC‐FC coupling than the PS group and the HC group in the right‐lesion analysis. In addition, both patient groups had weaker structural‐functional connectome correlation than the HCs. Conclusions The CS and PS groups both showed FC and SC disruption and the CS group had a weaker SC‐FC coupling than the PS group in the right lesion analysis. This may provide useful information for individualized rehabilitative strategies.

Distinct brain structural‐functional network topological coupling explains different outcomes in tinnitus patients treated with sound therapy

“…Then, we used fiber assignment by a deterministic fiber tracking algorithm for whole-brain fiber tractography. In this process, consistent with prior studies, we set FA 0.15 or a turning angle >45 as the termination criterion of continuous fiber (Chen, Geng, et al, 2021;Cui et al, 2013).…”

“…The method used for SC-FC coupling analysis in this research was in line with previous studies (Chen, Geng, et al, 2021;Honey et al, 2009;Suo et al, 2021). The nonzero network edges of the SC matrix were extracted, rescaled to a Gaussian distribution, and then…”

“…Decreased SC-FC coupling may suggest a loss of coherence of functional and structural connectomes (Zhang, Shao, et al, 2019). Disrupted SC-FC couplings have been reported in many diseases, such as stroke, Alzheimer's disease, epilepsy, and schizophrenia, and SC-FC coupling is correlated with clinical symptoms (Cao et al, 2020;Chen, Geng, et al, 2021;Cui et al, 2019;van den Heuvel et al, 2013;Wang, Dai, et al, 2015). In line with these studies, we found that patients in the IG had a significant increase in SC-FC coupling compared to HCs, while there was no significant difference between the EG and HCs.…”

“…Analysis employing a combination of structural connectivity (SC) and functional connectivity (FC) networks has been proposed in recent years (Honey, Thivierge, & Sporns, 2010 ). This measurement, known as SC‐FC coupling, has been applied to investigate changes in SC‐FC network relationships in numerous neurologic disorders (Chen et al, 2021 ; Huang & Ding, 2016 ; Suo et al, 2021 ; Zhang, Shao, et al, 2019 ). For instance, Chen, Geng, et al ( 2021 ) found differences in SC‐FC coupling in patients with different types of subcortical stroke, which was closely correlated to their clinical performance.…”

“…This measurement, known as SC‐FC coupling, has been applied to investigate changes in SC‐FC network relationships in numerous neurologic disorders (Chen et al, 2021 ; Huang & Ding, 2016 ; Suo et al, 2021 ; Zhang, Shao, et al, 2019 ). For instance, Chen, Geng, et al ( 2021 ) found differences in SC‐FC coupling in patients with different types of subcortical stroke, which was closely correlated to their clinical performance. However, to the best of our knowledge, there have been no studies thus far that have explored the alterations in SC‐FC network couplings in patients with idiopathic tinnitus who had different outcomes after sound therapy.…”