Network Disconnection Syndrome in Unruptured Brain Arteriovenous Malformations: A Multimodal Connectome Study

Area of Science:

• Neuroscience
• Medical Imaging
• Network Science

Background:

• Cognitive impairment is a poorly understood complication of brain arteriovenous malformations (bAVM).
• Traditional explanations focus on hemodynamic steal or tissue destruction, but the role of network disruption is unclear.
• Understanding the link between structural pathology and cognitive variability in bAVM is crucial.

Purpose of the Study:

• To investigate the relationship between structural brain damage and cognitive performance in patients with bAVM.
• To compare network disruption in bAVM patients with healthy controls.
• To identify predictors of cognitive decline in bAVM.

Main Methods:

• Recruited patients with unruptured bAVM and matched healthy controls.
• Integrated lesion mapping, morphometry, and Network Diffusion Modeling (NDM).
• Evaluated lesion load, cortical remodeling, and white matter connectivity as predictors of cognitive performance.

Main Results:

• bAVM patients showed reduced structural network efficiency, a stronger predictor of cognitive decline than lesion volume.
• Global functional networks were preserved, but local reorganization did not prevent deficits.
• Structure-function decoupling in association networks correlated with executive and memory impairment.

Conclusions:

• Cognitive dysfunction in bAVM is a disconnection syndrome due to white matter tract disruption.
• Functional compensation has limitations, and volumetric assessment is insufficient.
• Preoperative connectome mapping of white matter integrity can aid risk stratification and treatment planning.