Photon Migration Simulator for Fluorescence Tomography

Analytically predicting photon paths in real -high scattering- anisotropic tissues is extremely complex, due to the significant random scattering events that photons suffer as they traverse the tissue, especially at boundaries between areas with different optical properties. An statistically correct optical and anatomical model of photon trajectories inside laboratory animals will therefore improve considerably our understanding about how light diffuses within the animals, and therefore help us designing efficient experimental setups and reconstruction algorithms for fluorescence mediated tomography (FMT). Here, we present new simulations of photon propagation and fluorescence emission in anisotropic media using realistic models of laboratory animals and a Monte Carlo (MC) based approach. We compare the MC simulation results with an approximation of the solution of the diffusion equation using finite differences and discuss the different behaviour of the two methods.