P07.13.A ENHANCING NEUROSURGICAL GUIDANCE IN GLIOBLASTOMA USING NITROGEN VACANT (NV) DIAMOND QUANTUM SENSING

Abstract BACKGROUND Accurate intraoperative delineation of tumor from eloquent brain is critical for safe and efficient glioblastoma resection. Conventional neuro-navigation offers anatomical guidance but lacks real-time functional feedback and is subject to brain shift, whereas quantum sensing based on nitrogen-vacancy (NV) centers in diamond provides contactless magneto-physiological recordings. We evaluate and present a novel platform that is able to profile the magnetic activity in a neural tissue preparation. METHODS Human cortical tissue sections were inoculated with GBM cells and maintained ex-vivo as previously reported. Ground-truth magnetic recordings were acquired with a rubidium vapor-cell magnetometer (QZFM-v1.5, QuSpin) with a 15ft/sqrt(Hz) noise floor. A compact NV-diamond sensor with a 30pT noise floor was then positioned to capture spontaneous and evoked magnetic activity in both infiltrated and non-infiltrated regions, previously mapped using high-resolution fluorescence imaging scans of the experimental tissue sections. Glial cell viability assays (Immunostaining, live/dead staining) were used to assess any detrimental effects due to the microwave exposure during data acquisition. RESULTS QuSpin recordings confirmed detectable magnetic transients corresponding to neural activity. The NV sensor was able to capture fluctuations in the neural environment due to differential treatments with high fidelity, demonstrating the presence of magneto-physiological activity in a millimeter-scale preparation. Safety assays revealed no significant changes in glial activation by means of metabolic assays as well as morphometric analysis after repeated NV associated microwave exposure, both acutely as well as with temporal delay (<1hr, 24hrs, p > 0.05). Peritumoral regions exhibited increased activity upon glutamatergic activation, providing spatially resolved functional context. CONCLUSIONS We present evidence that our novel NV-platform can detect magneto-physiological activity, without detrimental effects to the tissue microenvironment. This approach holds promise for real-time, NV diamond quantum sensor-based guidance in neuro oncological surgery.