Evaluation of New Flexible High-density Intra-operative ECoG Electrodes for Epilepsy Surgery. ( EpiGrid )

Inclusion Criteria: * Age ≥18 years at the time of enrolment * Lesional epilepsy (incl. secondary mesial temporal sclerosis) that is considered a candidate for intra-operative high-density grid recordings (incl. patients who underwent sEEG preceding resective surgery) * Provided informed consent for study participation by the subject Exclusion Criteria: * Occipital lesion * Surgeries involving a primary mesial temporal lesion, a disconnection, or hemispherectomy. * Planned ioECoG recordings during fully awake surgery and/or functional recordings * Use of anticoagulants that cannot be discontinued during the perioperative period, or a factor XIII deficiency or any other haematological disease * Active participation in another investigational device study * Any other condition that in the opinion of the investigator may adversely affect the safety of the subject or would limit the subject's ability to complete the study. * Insufficient understanding of Dutch language.