Intraoperative stimulation techniques for functional pathway preservation and glioma resection

Although a primary tenet of neurosurgical oncology is that survival can improve with greater tumor resection, this principle must be tempered by the potential for functional loss following a radical removal. Preoperative planning with functional and physiological imaging paradigms, combined with intraoperative strategies such as cortical and subcortical stimulation mapping, can effectively reduce the risks associated with operating in eloquent territory. In addition to identifying critical motor pathways, these techniques can be adapted to identify language function reliably. The authors review the technical nuances of intraoperative mapping for low- and high-grade gliomas, demonstrating their efficacy in optimizing resection even in patients with negative mapping data. Collectively, these surgical strategies represent the cornerstone for operating on gliomas in and around functional pathways.