Intracranial EEG Monitoring and Electrical Stimulation Mapping

This chapter delves into the relevance of intracranial EEG monitoring and electrical stimulation mapping in epilepsy surgery. Intracranial EEG monitoring is utilized to identify the epileptogenic zone in patients with medically refractory epilepsy. We discuss the indications for intracranial monitoring, emphasizing its efficacy in discordant cases, MRI-negative neocortical epilepsy, and cases requiring detailed functional mapping. The utility of intra-operative electrocorticography (ECOG) is outlined, emphasizing its limitations. The chapter also explores electrode types, analysis techniques, recommended implantation schemes for SEEG, surgical outcomes and safety. Electrical stimulation mapping (ESM) for identifying eloquent cortex and seizure provocation is discussed, detailing stimulation parameters, critical regions, and mapping of various brain functions. The limitations and safety considerations are discussed, providing a comprehensive overview of intracranial evaluation’s evolving role in epilepsy surgery.