Presurgical Motor Mapping With Transcranial Magnetic Stimulation (TMS)

The aim of the study is to examine the degree of concordance between presurgical neuronavigation guided TMS (nTMS) and direct cortical stimulation (DCS) in identifying hand motor cortex in adults undergoing epilepsy surgery. Navigated transcranial magnet stimulation (nTMS), MagStim RapidStim2 Magnetic stimulation will be delivered to hand primary motor cortex, with positive and negative functional sites determined through surface electromyography (EMG). The study will involve patients ages 12-60 years, with planned neurosurgery involving implantation of intracranial subdural electrodes including over the precentral gyrus. Navigated transcranial magnet stimulation (nTMS), MagStim RapidStim2 Magnetic stimulation will be delivered to hand primary motor cortex, with positive and negative functional sites determined through surface electromyography (EMG). The primary outcome measure will be spatial correlation between topographic maps of hand motor representation obtained through nTMS compared to direct, extra-operative cortical stimulation performed as part of routine clinical care. A secondary outcome measure will be safety and tolerability of TMS in the epilepsy patients.