The nature, frequency and value of stimulation induced seizures during extraoperative cortical stimulation for functional mapping

Direct electrical cortical stimulation (CS) is used for mapping of eloquent cortex in patients with refractory focal epilepsy undergoing intracranial electroencephalography (icEEG) as part of their presurgical evaluation. CS can be performed with subdural grids, strips and depth electrodes (or combinations of these) after craniotomy or with stereotactically-inserted depth electrodes (stereo electroencephalography, SEEG)[1,2]. CS remains the gold standard for functional mapping of language, motor and sensory areas in relation to the epileptogenic zone (EZ) prior to epilepsy surgery[1,2].