Robust reconstruction of fluorescence molecular tomography based on a two-stage matching pursuit method for in vivo orthotopic hepatocellular carcinoma xenograft mouse model

摘要

As a promising tomographic method in preclinical research, fluorescence molecular tomography (FMT) can obtainreal-time three-dimensional (3D) visualization for in vivo studies. However, because of the ill-posed nature and sensitivityto noise of the inverse problem, it remains challenging for effective and robust reconstruction of fluorescent probedistribution in animals. In this study, we present a two-stage matching pursuit (TSMP) method. The iterative process isdivided into two processes: In the first stage, we iterate several times using the OMP algorithm to improve the accuracy ofthe support set, which is because most of the atoms selected by the OMP algorithm are accurate. In the second stage, we useCoSaMP algorithm to iterative. The initial input of the second stage is the residual and atom obtained by the first stageOMP algorithm, which can change the dependence of CoSaMP to sparsity. Meanwhile, considering the time ofreconstruction, we set the iterative times of the first stage to K/2 (K is the sparisty). Because of the accuracy of the initialoutput and the choice of atomic criteria, the proposed algorithm has better performance than OMP and CoSaMP algorithm.The result of numerical simulation show that TSMP method can not only achieves accurate and desirable fluorescentsource reconstruction, but also demonstrates enhanced robustness to noise.