Use of systematic stimulation mapping and functional/structural imaging to improve localization of seizure onset in patients with drug‐resistant epilepsy

Abstract

Despite the advantages of using Stereotactic Electrode Encephalography (SEEG) to demarcate epileptogenic onset zones, there are limitations to utilizing SEEG as a method to accurately map the epileptogenic network in patients with drug‐resistant epilepsy. The objective of this study is to use patient‐specific cortical and subcortical segmentations from pre‐electrode implantation structural MRI and post‐electrode implantation CT scans to assess the likelihood that SEEG electrodes are implanted in common eloquent cortex foci across subjects. We assessed the association between seizure foci, semiology, and cortical localization of electrode implantation in 10 patients to provide a three‐dimensional neuroanatomical representation of a patient's epileptogenic network. We hypothesized that there is a common set of eloquent cortical areas targeted among analyzed patients and that functional features of patient semiology will predict cortical localization of seizures and correlate with neurologist‐identified, SEEG‐defined, epileptogenic sites. We used a novel analysis pipeline based on a recently published method (MATLAB iElvis toolbox) and FreeSurfer to prepare pre‐electrode implantation patient MRI and post‐electrode implantation CT scans to build a patient‐specific three‐dimensional model, corrected for brain shift. Electrodes were mapped in 3D‐space in BioImage Suite software. Cortical brain areas were later mapped and merged with 3D‐model of patient‐specific electrodes. Data were analyzed for correlation of electrode, cortical location, and patient semiology.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.