Mapping grey matter and network abnormalities in seizure-onset patterns via stereotactic EEG
Tao Feng1, Yanfeng Yang1, Yihe Wang1
1Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China; China International Neuroscience Institute (CHINA-INI), Beijing, China.
Neurobiology of Disease
|July 7, 2025
Summary
Mesial temporal lobe epilepsy (MTLE) seizure-onset patterns (SOPs) show distinct brain differences. Individualized structural covariance networks (IDSCNs) better predict surgical success than voxel-based morphometry (VBM) in MTLE patients.
Area of Science:
- Neurology
- Neuroimaging
- Epilepsy Research
Background:
- Mesial temporal lobe epilepsy (MTLE) is the most common focal epilepsy resistant to medication.
- Seizure-onset patterns (SOPs), like hypersynchronous (HYP) and low-voltage fast (LVF) rhythms, classify MTLE.
- Underlying morphological and network differences between SOPs, and their prognostic value, are not well understood.
Purpose of the Study:
- To investigate the distinct morphological and network abnormalities associated with HYP and LVF seizure-onset patterns in MTLE.
- To compare the predictive value of voxel-based morphometry (VBM) and individualized structural covariance networks (IDSCNs) for surgical outcomes in MTLE.
- To explore network subtypes and their relationship with SOPs in MTLE.
Main Methods:
- Analysis of high-resolution MRI and stereotactic EEG data from 55 MTLE patients and 37 healthy controls.
- Voxel-based morphometry (VBM) to identify grey matter volume (GMV) abnormalities.
- Individualized structural covariance networks (IDSCNs) to assess patient-specific network disruptions.
- Hierarchical clustering for network subtype exploration and ROC analysis for outcome prediction.
Main Results:
- HYP-onset MTLE showed ipsilateral mesial temporal atrophy and widespread bilateral network disruptions (hippocampus, supramarginal gyrus) with interhemispheric connectivity issues.
- LVF-onset MTLE exhibited subcortical abnormalities and hemispheric network disruptions (fusiform gyrus) with limited interhemispheric spread.
- Both SOPs displayed basal ganglia abnormalities; hierarchical clustering identified SOP-specific network subtypes.
- IDSCN measures were superior to VBM in predicting surgical outcomes.
Conclusions:
- Distinct morphological and network abnormalities are associated with different SOPs in MTLE.
- IDSCNs show promise for personalized treatment planning and prognostic evaluation in MTLE.
- Further research into network-based biomarkers for MTLE is warranted.
