Emerging Imaging and Operative Techniques for Glioma Surgery

Fluorescence-guided surgery for brain tumors

“…The specificity decreases with a fading signal intensity as the tumor load within the area of infiltration drops down to the threshold limit of detection. Under optimal conditions with an operation microscope and standard fittings for a 400-440-nm excitation light source, that threshold of detection appears to equate to a concentration of 1 µg/ml of PpIX, which approximately corresponds to a tumor cellularity of 4.5% [19,20]. Thus, the area of detection limit defines a region where infiltration sometimes constitutes solitary glioma cell infiltration, for actively migrating HGG cells also contribute to the overall aspect of the fluorescent signal [21].…”