Three-dimensional bioluminescent source reconstruction method based on nodes of adaptive FEM

As a novel and rapidly growing optical molecular imaging technology, bioluminescence tomography (BLT) can localize and quantify an internal bioluminescent source with the bioluminescent signal on the external surface of a small animal to reveal non-invasive molecular and cellular activities directly. Adaptive finite element method (FEM) based on discretized elements has been introduced into BLT field recently, but the quickly increasing number of subdivided elements will reduce the source reconstruction efficiency greatly along with mesh refinement. In this contribution, a three-dimensional BLT reconstruction method based on nodes of adaptive FEM is developed for determining bioluminescent source distribution to solve the aforementioned problem, which can improve localization of source and enhance the efficiency of reconstruction. Furthermore, BLT is ill-posed for high scattering properties of the biological tissues and the limited boundary detection data. Thus, adequate a priori knowledge should be incorporated in this proposed algorithm to reduce the ill-posedness of BLT, such as optical parameters and anatomical structures information of the tissues. Finally, the performance of this reconstruction method is verified with the homogeneous and heterogeneous mouse chest phantoms and Monte Carlo (MC) simulation data. The results show the effectiveness and merits of this tomographic algorithm for BLT.