简化球谐近似与拉普拉斯正则化的FMT成像方法

Fluorescence molecular tomography method using simplified spherical harmonics approximation and Laplace regularization

荧光分子断层成像作为一种先进的光学分子影像,可以有效重建小动物体内荧光团的浓度和三维空间分布信息,实现肿瘤的早期检测.为了提高重建的图像性能,针对扩散模型只适合高散射低吸介质的局限性,采用基于辐射传输方程的简化球谐近似模型进行前向模拟,同时为克服重建过程的病态性,应用一种融合结构信息的拉普拉斯正则化方法进行图像重建.数值仿真实验结果表明,该方法能够获得较高质量的重建图像,尤其对于小荧光团和多荧光团成像.

As an emerging optical molecular imaging technology, fluorescence molecular tomography can efficiently reconstruct concentrations and three dimensional distributions of the buried fluorophore in small animals and diagnose the early cancer. For the purpose of improving the performance of the reconstructed image, simplified spherical harmonics approximation （SPN） based on the radiative transport equation （RTE） is proposed to perform the forward simulation. To overcome the influence of ill-posedness and receive a more accurate reconstructed image, the Laplace regularization method is introduced to reconstruct the inverse problem. Numerical experiments reveal that the proposed method can acquire high-quality reconstructed images, especially of the small object and multi objects.