Abstract
OBJECTIVE
Aggressive, even supramarginal, resection without compromising the neurological status of the patient remains a great challenge in the management of glioma cases. Accurate cortical and subcortical functional mapping allows more radical glioma resection. Numerous imaging, electrophysiological, and hybrid methodologies have been employed in the cortical mapping of patients with gliomas in eloquent areas. Despite the recent advances of these non-invasive modalities, direct electrical cortical and subcortical stimulation and mapping through an awake craniotomy remains the gold standard for maximal glioma resection and preservation of eloquent cortex functions. Extraoperative stimulation and mapping via implanted subdural and/or depth electrodes may be a valid alternative mapping method in these cases that an awake procedure is not feasible. The role of this mapping method is examined in our current study.
MATERIAL & METHODS
In a retrospective study, 51 patients undergoing extraoperative stimulation and mapping for glioma resection were included. The demographic data, the clinical characteristics, the stimulation parameters and complications, the extent of resection, the perioperative complications, and the tumor histological grade were analyzed. Shapiro-Wilk test, as well as uni- and multi-variate regression analysis was used for our statistical analysis.
RESULTS
The mean age of our participants was 58 (SD: 9.4) years. The location of the glioma was on the left side in 80.4%, while the frontal lobe was affected in 51.0%. Extraoperative cortical and subcortical stimulation and mapping was successful in 94.1%. The median stimulation procedure was 2.0 hours, while the median implantation time was 72 hours. Stimulation-induced seizures occurred in 13.7%, while CSF leakage in 5.9% of our cases. The mean extent of resection was 91.6%, while transient dysphasia occurred in 21.6%, and transient hemiparesis in 5.9% of our cases.
CONCLUSIONS
Extraoperative stimulation and mapping constitutes a valid alternative mapping option in glioma patients, who cannot undergo an awake craniotomy.