Pathophysiological findings explored via epilepsy surgery

Abstract

This report describes the surgical indications for various epilepsy types and demonstrates the standard procedure and anatomy for mesial temporal lobectomy. In addition, we introduce the original technique of multiple subpial transection of hippocampus to preserve memory function. Real-time mapping by electrocorticogram is practically useful to obtain rough functional distributions on the electrodes. HGA indicates the most essential areas related to each task and clearly indicates the language related areas. Linguistic HGA mapping quickly identified the language area in the temporal lobe. Furthermore electric stimulation by linguistic HGA mapping to the identified temporal receptive language area evokes CCEP on the frontal lobe. The combination of linguistic HGA and frontal CCEP, which is called “Super Passive Mapping” does not need any patient cooperation and the sensitivity and specificity are 93.8% and 95%, respectively. In epilepsy surgery, there have been additional surgical options to control seizures, such as disconnection of abnormal networks, measuring cortico-cortico evoked potentials and vagal nerve stimulation. Finally, we refer to depth electrodes and laser ablation as novel diagnostic and treatment techniques.