Study of Predictive Biomarkers for Rational Management of Drug-resistant Epilepsy Associated With Focal Cortical Dysplasia

Study Overview
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Brief Summary
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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.

Official Title
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Study of Predictive Biomarkers for Rational Management of Drug-resistant Epilepsy Associated With Focal Cortical Dysplasia

Conditions
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Refractory Epilepsy, Focal Epilepsy, Focal Cortical Dysplasia

Intervention / Treatment
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* Procedure: visual and quantitative SEEG signal analysis
* Procedure: Resective epilepsy surgery procedure


Participation Criteria
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Eligibility Criteria
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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.

Ages Eligible for Study
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Minimum Age: 2 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| The SEEG group<br>Group with the SEEG analysis | Procedure: visual and quantitative SEEG signal analysis<br>* signal SEEG analysis<br>Procedure: Resective epilepsy surgery procedure<br>* Surgical removal of the epileptogenic brain area<br>|
| The direct surgery group<br>Group with a direct surgery | Procedure: Resective epilepsy surgery procedure<br>* Surgical removal of the epileptogenic brain area<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of seizure-free patients (Engel class I) at 12-months follow-up after resective surgery. |  | 12 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of each of six seizure-onset pattern types within each of three histologically defined subgroups (FCD type I, FCD type II, non-pathologic findings). |  | 12 month | 
| Duration of epilepsy before surgery in patients with focal and network epileptogenic zone (defined by EI) |  | 12 month | 
| Topographic distribution of structures that disclose high Epileptogenicity Index values (EI>0.4), of structures with maximal interictal HFO rates and of structures showing interictal/preictal functional connectivity alterations |  | 12 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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focal cortical dysplasia, Pronostic, Epilepsy surgery, Epiletogenicity index, SEEG