Transorbital intraoperative electrocorticography-guided surgical resection for medically refractory developmental epileptic encephalopathy with spike-wave activation in sleep

•EEG abnormalities in sleep and developmental delay/regression are typical of DEE-SWAS.•Surgical interventions remain uncommon for DEE-SWAS.•An 11-year-old boy with a history of epilepsy presented with refractory DEE-SWAS.•iECoG was employed to guide extent of resection of a focus adjacent to Broca’s area.•Surgery resulted in improved cognitive function and resolution of EEG abnormalities. Developmental epileptic encephalopathy with spike-wave activation in sleep (DEE-SWAS) is an epilepsy syndrome of childhood characterized by developmental delay or regression with significant abnormal epileptiform activity during sleep. In some cases, DEE-SWAS with an identified focal lesion is treated with surgical resection. The authors report an unusual case of focal DEE-SWAS that was successfully treated via transorbital resection with intraoperative electrocorticography (iECoG). The patient is an 11-year-old boy with a history of medication-responsive seizures who presented with cognitive and language decline. Electroencephalography demonstrated abnormal electrographic activity during sleep consistent with DEE-SWAS. Imaging and electrographic studies identified a probable epileptogenic zone anterior and adjacent to Broca’s area. He underwent stereoelectroencephalography followed by focal resection with iECoG, which resulted in resolution of EEG abnormalities, improved word finding, and no further cognitive decline. While DEE-SWAS is not typically managed with surgical intervention, focal resection in carefully selected patients can achieve favorable outcomes.