One-step fluorescence photoacoustic tomography with the optical radiative transfer model

We present adjoint-based Jacobian as well as gradient evaluations and corresponding reconstruction schemes to solve the fully nonlinear, optical radiative transfer modeled one-step fluorescence photoacoustic tomographic (FPAT) problem, which aims to reconstruct the map of absorption coefficient of the exogenous fluorophore from boundary photoacoustic data. The radiative transport equation (RTE) and frequency-domain photoacoustic equation have been employed to model light and photoacoustic wave propagation, respectively. Levenberg-Marquardt and Broyden-Fletcher-Goldfarb-Shanno reconstruction schemes have been used corresponding to the evaluated Jacobians and gradients, respectively. Numerical reconstructions obtained from the two schemes have been validated for scattering-dominant as well as nonscattering-dominant media in 2D. To the best of our knowledge, these are the first one-step FPAT reconstruction results in literature based on the optical RTE model.