Is Protein S100B a Predictor of First-to-chronic Seizure Conversion in Adults?

Inclusion Criteria: * The patient has been correctly informed. * The patient must have given his informed and signed consent. * The patient must be insured or beneficiary of a health insurance plan. * The patient is at least (≥) 18 years old and less than (\<) 60 years old. * The patient has experienced a first generalized, epileptic seizure (patients with partial onset and secondary generalization can also be included). * The seizure has occurred less than 24 hours ago. Exclusion Criteria: * The patient is participating in another study that may interfere with the results or conclusions of this study. * Within the past three months, the patient has participated in another study that may interfere with the results or conclusions of this study. * The patient is in an exclusion period determined by a previous study. * The patient is under judicial protection. * The patient refuses to sign the consent. * It is impossible to correctly inform the patient. * The patient is pregnant or breast-feeding (MRI contraindicated). * Patient has a previous abnormal brain imaging (MRI). * Patient has abnormal biological tests for toxicology (alcohol, cocaine and cannabis tests), blood ionogram (hyponatremia \<130mM), liver enzymes (\>5N), inflammatory syndrome (elevated C-reactive protein).