Focal Cortical Dysplasias (FCDs) are neurodevelopmental disorders that represent a major cause of early onset drug-resistant epilepsies with cognitive and behavioral impairments, carrying a lifelong perspective of disability and reduced quality of life. Despite a major medical and socio-economic burden, rationale therapeutic strategies are still under debate. Surgical removal of the epileptogenic brain area (Epileptogenic Zone) is the most successful treatment, yet it fails to control FCD-associated seizures in as much as 40% of cases. Precise definition and complete resection of the Epileptogenic Zone are the main determinants of outcome. In current practice of French centers, up to 80% FCD-patients require an intracranial EEG (icEEG) recording to accurately define the epileptogenic zone. However, the indications for icEEG in MRI-visible FCD remain empirical and are essentially based on expert opinion.
Eligibility Criteria
Inclusion Criteria:
- Adult or pediatric patient suffering from drug-resistant focal epilepsy?
- Age more than 2 years old;
- Brain MRI suggestive of FCD or normal?
- Standardized presurgical evaluation available including medical history, scalp video-EEG, 3T MRI, FDG-PET, Neuropsychological tests?
- Inpatient in one of the participating centers for recording seizure during long term scalp video-EEG and / or SEEG-monitoring?
- Resective surgery with a minimal post-operative follow-up of 12 months?
- Histopathologic evidence for FCD or non-pathologic findings (normal histology or mMCD type II).
- Patient, parents or legally representative who have given written informed consent to allow the study data collection procedures.
Exclusion Criteria:
- Brain MRI suggestive of another type of lesion?
- Difficulty to read or understand French, or inability to understand the information;
- Pregnant or breastfeeding woman;
- Subject under judicial protection.
- Other lesion discovered on histological examination?
- FCD type 3, dual pathology, ambiguous or unavailable neuropathological findings
- Lack of longitudinal pre- and post-surgical follow-up.