Topological Alterations in White Matter Structural Networks in Blepharospasm

Area of Science:

• Neuroscience
• Medical Imaging
• Network Science

Background:

• Existing research suggests localized white matter (WM) structural changes in blepharospasm (BSP) patients.
• However, the extent of large-scale WM structural network reorganization in BSP remains largely unexplored.

Purpose of the Study:

• To investigate topological and network feature alterations in large-scale WM structural networks in BSP patients.
• To compare these network changes in BSP patients against those with hemifacial spasm (HFS) and healthy controls (HCs).

Main Methods:

• A cross-sectional study utilizing graph theoretical analysis on diffusion tensor tractography data.
• Analysis of WM structural connectivity across 246 cortical and subcortical regions in 41 BSP patients, 41 HFS patients, and 41 HCs.
• Calculation and comparison of network topological parameters among the three groups.

Main Results:

• Both BSP and HFS patients displayed altered network integration and segregation (increased global efficiency, modularity; reduced shortest path length) compared to HCs.
• Increased nodal efficiency was observed in multiple cortical and subcortical regions for both BSP and HFS patients versus HCs.
• BSP patients, unlike HFS patients or HCs, showed unique additional hub regions in the primary motor cortex and basal ganglia.

Conclusions:

• The study indicates extensive reorganization of large-scale WM structural networks in BSP patients.
• These alterations are likely attributed to a combination of dystonia-specific abnormalities and facial hyperkinetic movements.
• Findings highlight significant network-level brain changes associated with blepharospasm.