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

Ido Ben Zvi; Noelle Enright; Felice D'arco; M Zubair Tahir; Aswin Chari; J Helen Cross; Christin Eltze; Martin M Tisdall

doi:10.1684/epd.2021.1368

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

Epileptic Disord. 2022 Feb 1;24(1):111-122. doi: 10.1684/epd.2021.1368.

Authors

Ido Ben Zvi¹, Noelle Enright², Felice D'arco³, M Zubair Tahir⁴, Aswin Chari⁴, J Helen Cross⁵, Christin Eltze⁵, Martin M Tisdall⁴

Affiliations

¹ Paediatric Neurosurgery Department. Great Ormond Street Hospital, UK.
² Paediatric Neurology Department. Great Ormond Street Hospital, UK.
³ Paediatric Radiology Department. Great Ormond Street Hospital, UK.
⁴ Paediatric Neurosurgery Department. Great Ormond Street Hospital, UK, UCL Great Ormond Street Institute of Child Health, UK.
⁵ Paediatric Neurology Department. Great Ormond Street Hospital, UK, UCL Great Ormond Street Institute of Child Health, UK.

PMID: 34750096
DOI: 10.1684/epd.2021.1368

Abstract

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 centre 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 paediatric 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<0.001), as was older age at seizure onset (p=0.03). Time from diagnosis to surgery, number of medications, type of surgery and histology were not associated with improved outcome.

Significance: Our data suggest that most children presenting with seizures and a radiological diagnosis of FCD will develop drug-resistant epilepsy and are candidates for epilepsy surgery. The main outcome predictors are the correlation between MRI and ictal EEG localization and age at onset. This suggests that patients with FCD and epilepsy may be considered for surgery before traditional criteria of drug resistance are met. This change in practice has the potential to improve quality of life and cognitive function, and reduce burden on epilepsy services.

Keywords: drug-resistant epilepsy; epilepsy surgery; focal cortical dysplasia.

MeSH terms

Child
Drug Resistant Epilepsy* / diagnosis
Drug Resistant Epilepsy* / epidemiology
Drug Resistant Epilepsy* / surgery
Early Diagnosis
Electroencephalography
Humans
Magnetic Resonance Imaging
Malformations of Cortical Development* / diagnostic imaging
Retrospective Studies
Seizures* / physiopathology
Treatment Outcome