Development of surgical confocal scanning microscope for intra-operative imaging of brain tumors using near infrared fluorescence: Technical note

We developed a confocal laser scanning microscope for intra-operative imagi ng of brain tumors using near infrared fluorescence. The quality of near in frared images of Indocyanine Green (ICG) was compared with the surgical con focal scanning (SCS) microscope and a conventional charge-coupled device (C CD) camera; we compared images of a tube filled with ICG, which was located in the mouse brain. Compared to the CCD camera, the SCS microscope could o btain a more precise image of ICG fluorescence through the brain tissue. In addition, the SCS microscope could image ICG fluorescence clearly in a rel atively light room because of elimination of stray light, while the CCD cam era required high darkness to obtain ICC images. The present SCS microscope can give useful intra-operative imaging of brain tumors, particularly dete ction of residual tumor tissues that extend into normal brain tissues.