Fluorescence lifetime imaging microscopy for brain tumor image-guided surgery

摘要

We demonstrate for the first time the application of an en-doscopic fluorescence lifetime imaging microscopy (FLIM) system to the intraoperative diagnosis of glioblastoma multiforme (GBM). The clinically compatible FLIM prototype integrates a gated (down to 0.2 ns) intensifier imaging system with a fiber-bundle (fiber image guide of 0.5 mm diameter, 10,000 fibers with a gradient index lens objective 0.5 NA, and 4 mm field of view) to provide intraoperative access to the surgical field. Experiments conducted in three patients undergoing craniotomy for tumor resection demonstrate that FLIM-derived parameters allow for delineation of tumor from normal cortex. For example, at 460±25-nm wavelength band emission corresponding to NADH/NADPH fluorescence, GBM exhibited a weaker florescence intensity (35% less, p-value <0.05) and a longer lifetime T_(GBM-Amean)= 1.59±0.24 ns than normal cortex T_(NC.Amean) = 1.28 + 0.04 ns (p-value <0.005). Current results demonstrate the potential use of FLIM as a tool for image-guided surgery of brain