Intraoperative brain mapping

Abstract

Surgical treatment of brain tumors near eloquent areas aims to achieve maximal tumor mass resection, while minimizing permanent morbidity risk. Preoperatively, the most widely used approaches to map brain areas related to specifi c functions are functional magnetic resonance imaging (fMRI) for cortical areas and diffusion tensor imaging (DTI) for subcortical pathways. Intraoperatively, brain mapping techniques allow identifi cation of both cortical motor and language areas and of corresponding subcortical tracts. Direct electrical stimulation (DES) is the gold standard method for the identifi cation and preservation of such areas during surgery. Different studies show that brain mapping increases resection rates and precision, decreasing risks of sequelae and improving overall survival in glioma surgery [ 8, 9, 11, 16 ]. During surgery, DES is used to plan the best surgical approach and to defi ne functional limits of resection, especially in cases where the distance between lesion location and functional cortex is 2 cm or less [ 23 ].