Children with seizures and radiological diagnosis of focal cortical dysplasia: can drug-resistant epilepsy be predicted earlier?

Objective: Focal cortical dysplasia (FCD) is a malformation of cortical development and is associated with drug-resistant epilepsy. Standard indication for epilepsy surgery is drug resistance (as defined by the ILAE). Given the high incidence of drug resistance in these children, this delay may not be warranted. The aim of the study was to determine the proportion of patients with a presumed FCD who develop drug resistance, and evaluate post-operative outcomes. Methods: This study incorporated a survey within a regional paediatric epilepsy network and a retrospective database review of a paediatric epilepsy center serving the network to identify children with epilepsy and a presumed FCD on MRI. Results: The survey revealed that 86% of the patients with epilepsy and presumed FCD on MRI within the network were referred to our centre. Of 139 pediatric patients included in the study, 131 (94.2%) had drug-resistant epilepsy. One hundred and ten (83.9%) patients were referred to epilepsy surgery, of whom 97 underwent surgery. Of 92 with one-year postoperative follow-up, 59.8% had an Engel Class 1 (seizure-free) outcome. Concordance of location between MRI and ictal EEG was strongly associated with Engel Class 1 outcome ( p