Multi-spectral diffusion MRI mega-analysis in genetic generalized epilepsy: Relation to outcomes.

Area of Science:

• Neuroimaging
• Epilepsy Research
• Diffusion MRI

Background:

• Genetic generalized epilepsy (GGE) is the most common epilepsy type.
• Previous GGE imaging studies had small cohorts, limiting subtype analysis.
• Group differences in GGE and subtypes like juvenile myoclonic epilepsy (GGE-JME) are known.

Purpose of the Study:

• To investigate microstructural brain differences in GGE and its subtypes using diffusion MRI.
• To assess the relationship between diffusion metrics and anti-seizure medication (ASM) response.
• To conduct a large-scale, multi-center diffusion MRI analysis.

Main Methods:

• A diffusion MRI mega-analysis of 192 participants (126 controls, 66 GGE patients) from four cohorts.
• Multi-site harmonization of imaging data.
• Analysis of fractional anisotropy (FA), mean, radial, and axial diffusivity (MD/RD/AD) in GGE, GGE-JME, GGE-GTCS, and GGE-AE.

Main Results:

• GGE patients showed decreased FA and increased RD compared to controls.
• JME patients had increased MD/RD; GGE-GTCS patients had decreased MD/AD.
• Refractory GGE patients had lower FA in the right cortico-spinal tract compared to non-refractory patients.

Conclusions:

• GGE and its subtypes exhibit distinct microstructural differences detectable by diffusion MRI.
• Microstructural changes correlate with treatment resistance in GGE.
• Findings support large-scale multi-site studies for GGE assessment and ASM refractoriness.