Connectome-based mapping of gray matter abnormalities in hepatic encephalopathy

Area of Science:

• Neuroscience
• Brain Imaging
• Connectomics

Background:

• Hepatic encephalopathy (HE) is associated with widespread gray matter abnormalities.
• The organization of these abnormalities within large-scale brain networks is not well understood.

Purpose of the Study:

• To investigate the spatial distribution of gray matter abnormalities in HE.
• To examine their relationship with brain network hubs, connectivity, and disease epicenters.

Main Methods:

• Cross-sectional MRI study of 45 HE patients and 45 controls.
• Analysis of cortical thickness and subcortical volumes.
• Connectome-based analyses using normative functional and structural connectomes.

Main Results:

• Widespread gray matter abnormalities in HE patients, particularly in prefrontal, motor, temporal, and limbic cortices, and basal ganglia/thalamus.
• Abnormalities did not align with normative functional or structural hubs.
• Structural neighborhood abnormalities correlated with cortical changes (r = 0.58, Pspin = 0.004).
• Functional and structural connectome epicenters identified, with prefrontal regions repeatedly implicated.

Conclusions:

• Gray matter abnormalities in HE are non-randomly organized and constrained by structural connectivity.
• Findings suggest prefrontal-centered disease epicenter networks are associated with HE brain changes.
• Provides connectome-based insights into the neurobiology of HE.