Super-passive language mapping for awake craniotomy using CCEP

Abstract

High gamma activity (HGA) between 80 and 140 Hz on electrocorticogram (ECoG) is assumed to reflect localized cortical processing, while cortico-cortical evoked potential (CCEP) can reflect bidirectional responses between language cortices when there is no patient cooperation. 20 patients with an intraaxial tumor in their dominant hemisphere, underwent lesion resections. We performed functional localization for the receptive language area, using real-time HGA mapping by listening to linguistic sounds. Furthermore, single electric pulses were delivered to the identified receptive temporal language area to detect CCEP in the frontal lobe. All mapping results were validated by ECS. Linguistic HGA mapping quickly identified the language area in the temporal lobe. Electric stimulation to the temporal receptive language area evoked CCEP on the frontal lobe. The combination of linguistic HGA and frontal CCEP did not need any patient cooperation or effort.