Background: In cases of medically refractory epilepsy that is multifocal or involving eloquent cortex, a combined resection and neuromodulatory approach may offer greater seizure reduction than resection alone. Here the authors describe indications, technical considerations, and outcomes of patients in whom resection and responsive neurostimulation (RNS) device implantation were performed in the same operation.
Observations: Three patients met inclusion criteria for this study. Preoperative sEEG demonstrated multifocal or eloquent cortex-involving seizure onset zones in all patients. In 2 patients, one depth electrode in the contralateral hippocampus and a cortical strip electrode ipsilateral to the resection were implanted. One patient received bilateral hippocampal depth electrodes and resection. Technical considerations include prioritization of stereotactic accuracy, avoidance of pulse generator discharge, and distant implantation of the generator relative to the resection site. At 1 year, 2 patients achieved Engel class IIIA, and 1 patient achieved class IIB.
Lessons: The authors suggest consideration of this combined approach of simultaneous RNS device implantation and craniotomy for resection when intracranial data indicate a role for resection but it is unlikely to achieve seizure freedom alone. https://thejns.org/doi/10.3171/CASE24895.
Keywords: MRE; RNS; case series; medically refractory epilepsy; multifocal epilepsy; neuromodulation; responsive neurostimulation.