Subdural Grid Electrode Placement: Approaches and Complications

Subdural grid electrode placement is a safe and effective technique for localizing an epileptic focus in medically refractory patients with discordant non-invasive testing. The specific approach taken is individualized on a patient-by-patient basis. However, the two goals of invasive monitoring with subdural electrodes are the same for every patient: define the volume of cortical tissue responsible for seizure onset and ‘map’ regions of functional tissue that may be impacted by resection of the epileptic focus. While complications are an accepted aspect of the procedure, they can be minimized through meticulous surgical technique, generous duroplasty, and careful postoperative sterility. Because of the heterogeneity of the published literature, we advocate standardized and data-registry-based outcome and complication measurements so that data can be more freely combined and analysed in the future.