For the roughly 25,000 Americans diagnosed annually with malignant brain gliomas, how much tumor a surgeon can safely remove remains one of the strongest predictors of survival. A comprehensive narrative review in the Journal of Neuro-Oncology maps the current technological ecosystem enabling surgeons to push resection further while protecting the neural architecture that defines a patient's functional identity — a balance that has historically been as much art as science.
The review synthesizes evidence across multiple intraoperative platforms. Awake craniotomy paired with direct electrical stimulation (DES) of cortical and subcortical tissue continues to anchor the field as the standard of care for tumors near eloquent regions, consistently lowering permanent neurological deficits while increasing rates of gross total resection. Fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA), which causes malignant glioma cells to emit pink-red fluorescence under violet light, and fluorescein sodium independently sharpen real-time tumor margin visualization; the review notes that combining both agents achieves greater extent of resection than either alone. Intraoperative MRI addresses the persistent problem of brain shift — the progressive displacement of neural tissue during surgery that renders pre-operative imaging increasingly inaccurate — and its integration with 5-ALA fluorescence is identified as the most robust currently available platform for safe maximal resection. Augmented reality navigation, overlaying three-dimensional virtual anatomy onto the live operative field, represents an emerging spatial orientation tool that further closes the gap between preoperative planning and real-time surgical reality.
This is a narrative review rather than a meta-analysis, which means it synthesizes the landscape without statistically pooling outcomes — an important caveat when evaluating strength of evidence. Nevertheless, the synthesis is clinically valuable because the individual technologies are rarely studied in combination, yet routinely used that way in practice. The finding that dual fluorescent-agent use outperforms either agent alone, and that iMRI plus 5-ALA represents the current ceiling for safe resection, gives neurosurgical teams a hierarchy of evidence to inform platform adoption decisions. The review also signals that local drug delivery — bypassing the blood-brain barrier entirely — represents the next integration frontier, potentially converting the surgical suite into a therapeutic delivery chamber rather than simply a resection event.