Epileptogenic Network Visualisation With Advanced MRI

Study Overview
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Brief Summary
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The goal of this clinical trial is to improve non-invasive identification of epileptogenic networks in drug-resistant epileptic patient. The investigators aim to compare epileptogenic network identification with stereo-EEG (used as glod standard) with the identification of the same network using advanced MRI (rs-fMRI, microstructural analysis of white matter, ...). The main goals are to: Compare the accuracy of network identification. Analyse the effect of the MRI sequences on candidates selection and target identification. Participants will already have been selected for stereoEEG and will undergo a supplementary MRI (about 1h) with the additional MRI sequences. Follow-up MRI are scheduled for patient undergoing a second, therapeutic epileptic surgery.

Official Title
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Epileptogenic Network Visualisation With Advanced MRI

Conditions
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Drug Resistant Epilepsy

Intervention / Treatment
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* Device: Advanced MRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient suffering from drug-resistant epilepsy Patient already selected for SEEG implantation as part of their epileptic networks Exclusion Criteria: Patient excluded from SEEG (pregnant women, children too young for the procedure, patient unable to undergo the procedure) Contra-indication for MRI

Ages Eligible for Study
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Minimum Age: 3 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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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Single Arm<br>Single Arm | Device: Advanced MRI<br>* resting-state functional MRI, diffusion with advanced post-processing (microstructure analysis), myelin mapping<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Network identification with MRI | Analysis of the anatomical overlap of radiological network (with MRI) and the electrophysiological network (with SEEG) using coregistration and a sublobar analysis. Overlap will be quantified in %. | At the end of phase 1 - expected to be 3 years after first inclusion | 
| Prognosis of network targetting with surgery | Analysis of the impact on epileptic outcome in accordance with effect of the surgery on the network. The impact of the surgery on the network will be assessed by coregistration to determine which part of the network has been removed or disconnected. The epileptic outcome will be assessed using the Engel classification | One year after surgery (phase 2) | 
| Interest of adding epileptic network radiological analysis in a standard epileptic work-up | Analyse the impact on therapeutic and/or diagnostic decision of the network radiological analysis in a standard clinical practice. This impact will be assessed by measuring the change in the type of decision (further work-up, invasive EEG, curative surgery, palliative surgery or no modification) or the modification in the extent of surgery (more/less electrodes for invasive EEG, more/less tissue targeted with surgery) | Approximately 1 year after the start of phase 3 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Network quantification | Analysis of the strength of the network using radiological data (r², Z-score, diffusion metrics obtained via microfingerprinting such as fiber volume fraction and fiber fraction) vs electrophysiological metrics (epileptogenic index, h²) | At the end of phase 1 - expected to be 3 years after first inclusion | 
| Network regulation with surgery | Analysis of the impact of the surgery on the radiological parameters of the network cited in outcome 4 (r² and Z-score for rsfMRI, number of tracts for tractography and strenght of tract with fiber fraction and fiber volume fraction for microfingerprinting) | One year after surgery (phase 2) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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epilepsy, network, non-invasive investigation