Focal epileptogenic lesions

Area of Science:

• Pediatric Neurology
• Epileptology
• Neuroimaging

Background:

• Focal epileptogenic lesions and their clinical impact differ between pediatric and adult epilepsy patients.
• Mesial temporal sclerosis (MTS), common in adult epilepsy surgery, is infrequent in children, often presenting as dual pathology when present.
• Pediatric epilepsy surgery candidates commonly exhibit lesions like cortical malformations, developmental tumors, or encephalomalacia.

Purpose of the Study:

• To delineate the distinct spectrum of focal epileptogenic lesions in pediatric epilepsy surgery candidates.
• To analyze how lesion characteristics, age at onset, and epilepsy onset influence the electroclinical phenotype in children.
• To emphasize the importance of surgical evaluation for pediatric medically refractory epilepsy with focal lesions.

Main Methods:

• Review of brain MRI characteristics to predict pathology.
• Histopathological evaluation as the gold standard for mass lesion diagnosis.
• Analysis of electroclinical phenotypes, considering lesion location, age at onset, and epilepsy onset.

Main Results:

• Brain MRI analysis is highly predictive of pathology in most pediatric epilepsy cases.
• Congenital or early acquired lesions in children can lead to generalized EEG features and seizure semiology.
• A subset of children with generalized epilepsy phenotypes benefit from surgical intervention.

Conclusions:

• Pediatric epilepsy surgery candidates present with distinct pathologies compared to adults.
• Age at onset of both the lesion and epilepsy significantly shapes the electroclinical phenotype in children.
• All children with medically refractory epilepsy and a focal lesion warrant surgical evaluation, regardless of EEG or semiology findings.