Development of a simulation environment for Cerenkov luminescence imaging

In vivo Cerenkov luminescence imaging (CLI) is a demanding application requiring advanced pre-clinical small animal optical imaging devices. Here we propose a Monte Carlo based simulation workflow aimed to improve the development of an efficient Cerenkov optical imager for small animals. Our work makes use of a modular approach by considering open source, freely available or custom built software to solve the forward light propagation problem from source to detector in the following steps: i) simulation of the efficiency of Cerenkov light production of beta-emitting radionuclide in tissue using GEANT4 ii) optical transport of the simulated emitted photons through a precise mouse CT-segmented model using Molecular Optical Simulation Environment (MOSE), iii) free space transport of light from the mouse surface to a CCD sensor and simulation of the system response. Results showed the effects of the choice of lens and sensor based on system characteristics. An internal 90-Y source was simulated considering a mouse phantom and the Cerenkov light detection by a CCD. We conclude that the modular approach presented in this work combines the strengths of the different simulation codes used and thus provides a complete work frame for optical simulations.