Adaptively Hybrid $3^{\text{rd}}$ Simplified Spherical Harmonics With Diffusion Equation-Based Multispectral Cerenkov Luminescence Tomography

Cerenkov luminescence tomography (CLT) can reproduce the location of the tumor inside the body and the physiological processes that are related to its biological behavior, it has thus attracted more attention in the field of imaging technology. The inadequacy of signals that are measured on the body surface might cause ill-posed problems during image reconstruction, thus affecting the quantitative accuracy of CLT. This can be improved using a multispectral strategy by providing more measurements. However, current reconstruction algorithms for multispectral CLT are based on the light transport model that uses a single equation (a diffusion equation or a 3
^rd
simplified spherical harmonics equation) for each spectrum, which cannot guarantee the accuracy and efficiency of the reconstruction. In order to make full use of the broad-spectrum characteristics of Cerenkov luminescence and ensure an accurate and efficient reconstruction, in this work we apply an adaptively hybrid model to the multispectral CLT, that can automatically select the light transport equation. Here, the hybrid model was not only applied to different spectra, but also to different tissues at a certain spectrum. The selection of the light transport equation was accomplished by automatically comparing the index with a predefined threshold. Our proposed method was evaluated with numerical simulations and mouse-based experiments and the results showed the feasibility and effectiveness of the adaptively hybrid model based multispectral CLT.