Safe surgery for glioblastoma: recent advances and modern challenges

One of the major challenges during glioblastoma surgery is balancing between maximizing extent of resection and preventing neurological deficits. Several surgical techniques and adjuncts have been developed to help identify eloquent areas both preoperatively (fMRI, nTMS, MEG, DTI) and intraoperatively (imaging (ultrasound, iMRI), electrostimulation (mapping), cerebral perfusion measurements (fUS)), and visualization (5-ALA, fluoresceine)). In this review, we give an update of the state-of-the-art management of both primary and recurrent glioblastomas. We will review the latest surgical advances, challenges, and approaches that define the onco-neurosurgical practice in a contemporary setting and give an overview of the current prospective scientific efforts

Impact of intraoperative stimulation mapping on high-grade glioma surgery outcome: a meta-analysis

Background: Intraoperative stimulation mapping (ISM) using electrocortical mapping (awake craniotomy, AC) or evoked potentials has become a solid option for the resection of supratentorial low-grade gliomas in eloquent areas, but not as much for high-grade gliomas. This meta-analysis aims to determine whether the surgeon, when using ISM and AC, is able to achieve improved overall survival and decreased neurological morbidity in patients with high-grade glioma as compared to resection under general anesthesia (GA). Methods: A systematic search was performed to identify relevant studies. Adult patients were included who had undergone craniotomy for high-grade glioma (WHO grade III or IV) using ISM (among which AC) or GA. Primary outcomes were rate of postoperative complications, overall postoperative survival, and percentage of gross total resections (GTR). Secondary outcomes were extent of resection and percentage of eloquent areas. Results: Review of 2049 articles led to the inclusion of 53 studies in the analysis, including 9102 patients. The overall postoperative median survival in the AC group was significantly longer (16.87 versus 12.04 months; p < 0.001) and the postoperative complication rate was significantly lower (0.13 versus 0.21; p < 0.001). Mean percentage of GTR was significantly higher in the ISM group (79.1% versus 47.7%, p < 0.0001). Extent of resection and preoperative patient KPS were indicated as prognostic factors, whereas patient KPS and involvement of eloquent areas were identified as predictive factors. Conclusions: These findings suggest that surgeons using ISM and AC during their resections of high-grade glioma in eloquent areas experienced better surgical outcomes: a significantly longer overall postoperative survival, a lower rate of postoperative complications, and a higher percentage of GTR

Global comparison of awake and asleep mapping procedures in glioma surgery: an international multicenter survey

Background Mapping techniques are frequently used to preserve neurological function during glioma surgery. There is, however, no consensus regarding the use of many variables of these techniques. Currently, there are almost no objective data available about potential heterogeneity between surgeons and centers. The goal of this survey is therefore to globally identify, evaluate and analyze the local mapping procedures in glioma surgery. Methods The survey was distributed to members of the neurosurgical societies of the Netherlands (Nederlandse Vereniging voor Neurochirurgie-NVVN), Europe (European Association of Neurosurgical Societies-EANS), and the United States (Congress of Neurological Surgeons-CNS) between December 2020 and January 2021 with questions about awake mapping, asleep mapping, assessment of neurological morbidity, and decision making. Results Survey responses were obtained from 212 neurosurgeons from 42 countries. Overall, significant differences were observed for equipment and its settings that are used for both awake and asleep mapping, intraoperative assessment of eloquent areas, the use of surgical adjuncts and monitoring, anesthesia management, assessment of neurological morbidity, and perioperative decision making. Academic practices performed awake and asleep mapping procedures more often and employed a clinical neurophysiologist with telemetric monitoring more frequently. European neurosurgeons differed from US neurosurgeons regarding the modality for cortical/subcortical mapping and awake/asleep mapping, the use of surgical adjuncts, and anesthesia management during awake mapping. Discussion This survey demonstrates the heterogeneity among surgeons and centers with respect to their procedures for awake mapping, asleep mapping, assessing neurological morbidity, and decision making in glioma patients. These data invite further evaluations for key variables that can be optimized and may therefore benefit from consensus