Multispectral fluorescence lifetime imaging system with Si avalanche photodetector: a better platform for clinical application

We report the design, development, and characterization of the first multispectral fluorescence lifetime imaging platform designed for clinical application based on avalanche photodiodes (APD). Consistent and accurate measurement of fluorescence lifetimes is achieved. Fast dynamic gain adjustment via APD bias modulation is implemented independently for each spectral channel, maximizing photon economy and greatly improving signal quality. Compared to conventional MCP-PMT based systems, the new platform presents 5-fold reduction of lifetime measurement variability under identical experiment conditions. This improved photon economy leads to 35 times faster coverage of imaging field in clinical practice with identical tissue exposure, making the new platform better suited for clinical application.