P07.08.B INTRAOPERATIVE ASSESSMENT OF GLIOMA USING MINIATURIZED EPI-FLUORESCENCE WIDEFIELD MICROSCOPE: A PROSPECTIVE COMPARATIVE STUDY OF EX-VIVO AND IN-VIVO APPLICATIONS

Abstract BACKGROUND This study evaluated the Miniaturized Epi-fluorescence Widefield Microscope (MEW-M) system using the EndoSCell™ device for intraoperative glioma assessment. MATERIAL AND METHODS The MEW-M system used a rapid staining protocol with fluorescein sodium and methylene blue. The study included 70 glioma patients (mean age 55.9 years, 57% male). Ex-vivo evaluation was done on central tumor core specimens, and in-vivo assessment on margin specimens at the tumor-brain interface. This study is registered with Chinese Clinical Trial Registry (ChiCTR2500101224). RESULTS For tumor core specimens, both pathologists and neurosurgeons achieved 100% sensitivity and accuracy. For margin specimens, pathologists had 100% sensitivity, 88.9% specificity, and 96.0% accuracy, while neurosurgeons had 100% sensitivity, 74.1% specificity, and 90.7% accuracy. In WHO grade stratification, both groups showed identical performance for low-grade gliomas (100% sensitivity, 75.0% specificity, 91.3% accuracy), but pathologists had superior specificity and accuracy for high-grade gliomas compared to neurosurgeons. The MEW-M system significantly reduced procedural time compared to frozen section analysis (3.42±1.04 vs 32.93±11.37 minutes). In tumor cavity assessment, MEW-M detected residual tumor in 74.2% of cases. CONCLUSION The study concluded that the MEW-M system is effective for glioma detection, reduces processing time, and provides comparable diagnostic performance to conventional methods, potentially improving surgical decision-making during glioma resection.