System and methods for wide-field quantitative fluorescence imaging during neurosurgery

We report an accurate, precise and sensitive method and system for quantitative fluorescence image-guided neurosurgery. With a low-noise, high-dynamic-range CMOS array, we perform rapid (integration times as low as 50 ms per wavelength) hyperspectral fluorescence and diffuse reflectance detection and apply a correction algorithm to compensate for the distorting effects of tissue absorption and scattering. Using this approach, we generated quantitative wide-field images of fluorescence in tissue-simulating phantoms for the fluorophore PpIX, having concentrations and optical absorption and scattering variations over clinically relevant ranges. The imaging system was tested in a rodent model of glioma, detecting quantitative levels down to 20  ng/ml. The resulting performance is a significant advance on existing wide-field quantitative imaging techniques, and provides performance comparable to a point-spectroscopy probe that has previously demonstrated significant potential for improved detection of malignant brain tumors during surgical resection.