Disrupted topology of the functional white matter connectome in thyroid-associated ophthalmopathy

Background

This study aims to investigate the changes in the topological organization of WM functional connectivity in individuals with TAO, providing a novel and insightful perspective on the functional disruptions that characterize this condition.

Methods

This study utilized resting-state functional Magnetic Resonance Imaging (rs-fMRI) to capture blood-oxygen-level-dependent (BOLD) signals and T1-weighted images from patients with TAO and healthy control subjects. Group-level masks for white matter were created to extract WM-related BOLD signals, facilitating the construction of a functional white matter network. Graph theory analysis was subsequently conducted to evaluate global metrics, nodal metrics, and modularity, alongside network-based analysis. Finally, support vector machines (SVM) were employed for classification.

Results

A functional white matter network comprising 128 nodes and their respective connections was identified. The graph theory analysis revealed significant differences primarily in the sigma characteristic of the global small-world metrics, with a notable decrease in betweenness centrality observed in the splenium of the corpus callosum. Modularity analysis indicated significant intra-module variations in modules 03 and 05, while strong inter-module connections were observed between modules 01 and 03, as well as between modules 02 and 04. Furthermore, network-based statistics (NBS) highlighted 13 networks that exhibited significant alterations in the TAO group compared to healthy controls, underscoring the potential impact of TAO on the organization of white matter networks.

Conclusion

In our study, we found that patients with TAO exhibited abnormalities in the white matter functional network regarding small-world metrics and modularity, which are related to visual and cognitive functions.