MELD

MELD maps focal cortical dysplasias (FCDs) from MRI and predicts postsurgical seizure freedom to characterize lesion distribution and improve outcome estimation in focal epilepsy.

Key Features:

• Multi-centre retrospective cohort: Assembled MRI and clinical data for 580 patients with FCD-related epilepsy from 20 epilepsy centers.
• MRI-based lesion maps: Included MRI-derived maps of individual FCDs for cortical localization.
• Clinical and surgical metadata: Incorporated demographic, clinical onset, and surgical outcome information alongside imaging.
• Cortex-wide lesion distribution mapping: Mapped FCD distribution across the cerebral cortex and identified non-uniform concentration in regions such as the superior frontal sulcus, frontal pole, and temporal pole.
• Age-of-onset correlations: Identified that earlier epilepsy onset (typically before age 10) associates with lesions in primary sensory areas, while later onset associates with association cortices.
• Lesion size by lobe: Observed that FCDs in the temporal and occipital lobes are generally larger than those in the frontal lobe.
• Predictive model for postsurgical seizure freedom: Developed a model with a positive predictive value of 70% and a negative predictive value of 61%, showing location-dependent seizure freedom probabilities (~30% to ~75% across cortical regions).
• Data-driven atlases: Generated atlases mapping FCD locations and regional postsurgical seizure freedom rates.

Scientific Applications:

• Radiological lesion detection: Guides targeted radiological searches for subtle FCDs on MRI based on lesion probability maps.
• Outcome prediction: Estimates individual probabilities of postsurgical seizure freedom using the predictive model and regional rates.
• Surgical planning and risk counseling: Informs surgical targeting and evidence-based risk counseling through location-specific outcome data.
• Lesion-topography studies: Enables investigation of relationships between lesion location, age of epilepsy onset, and lesion size across the cortex.

Methodology:

Compiled a retrospective multi-centre MRI cohort of 580 FCD patients with MRI-based lesion maps and clinical/surgical metadata, computed cortical lesion distribution maps, developed a predictive model for postsurgical seizure freedom, and produced data-driven atlases of FCD locations and regional seizure freedom rates.