Short and long-term photostability of 3D printed fluorescent phantoms for near-infrared diffuse optical imaging

We have successfully printed an anatomically shaped hand model with properties similar to in vivo investigations with a fluorescence hand imager using indocyanine green (ICG). By adding the fluorescent dye Lumogen IR 765, titanium dioxide powder and black ink to a 3D printing methacrylate photopolymer we realized phantoms with physiologically relevant absorption and reduced scattering coefficients as well as fluorescence properties similar to the widely applied contrast agent ICG. The phantoms show an excellent long-term photostability making them well suited for device performance monitoring and comparison. In contrast, fluorescence of phantoms printed with ICG continuously decreases over time.