The Stereoelectroencephalography Methodology Applied to Epilepsies with a Visible Lesion.

Resective epilepsy surgery relies on accurate preoperative localization of the epileptogenic zone (EZ), so presurgical evaluation is necessary to obtain the most accurate information from clinical, anatomic, and neurophysiologic aspects, with the ultimate goal of performing an individualized surgical treatment. The noninvasive methods of seizure localization are complementary and results must be interpreted in conjunction, in an attempt to compose localization hypotheses of the anatomic location of the EZ. Stereoelectroencephalography is an extraoperative invasive method that is applied in patients with medically refractory focal epilepsy in order to anatomically define the EZ and the related functional cortical areas.