Brain Tumor Boundary Detection System Using 2-Color Photo-Dynamic Diagnosis

In the neurosurgery of brain tumor, patients' life after surgery crucially depends on completeness of malignant glioma resection. For decades, Photo-Dynamic Diagnosis using some oncotropic dyes (sensitizers) has been being improved as a surgical navigation system. In another field of medical diagnosis, a ratio metric technique, e.g. fluorescence ratio imaging, was applied to tumor detection, in which not only fluorescence from sensitizer, but also intrinsic auto-fluorescence were used to diagnose tumor lesions. However, it has never developed exhaustively in terms of signal noise ratio and resolution with system configuration, especially when applied to brain tumor boundary detection. In this study, in order to demarcate the brain tumor, “2-Color Photo-Dynamic Diagnosis System”, based on fluorescence ratio imaging, was constructed with higher sensitivity and resolution. This real time surgery navigating system, consisted of two CCDs and spectroscopic adaptor, can take better account of fluorescence spectroscopic characteristics. This was experimentally applied to brain tumor detection. Consequently, it was quantitatively confirmed that the contrast between tumor lesions and normal tissue could be enhanced. The present system was clarified to be effective to brain tumor monitoring and surgical delimitation.