This work concerns a fluorescence optical projection tomography system for low scattering tissue, like lymph nodes, with angular-domain rejection of highly scattered photons. In this regime, filtered backprojection (FBP) image reconstruction has been shown to provide reasonable quality images, yet here a comparison of image quality between images obtained by FBP and iterative image reconstruction with a Monte Carlo generated system matrix, demonstrate measurable improvements with the iterative method. Through simulated and experimental phantoms, iterative algorithms consistently outperformed FBP in terms of contrast and spatial resolution. Moreover, when projection number was reduced, in order to reduce total imaging time, iterative reconstruction suppressed artifacts that hampered the performance of FBP reconstruction (structural similarity of the reconstructed images with “truth” was improved from 0.15 ± 1.2 × 10⁻³ to 0.66 ± 0.02); and although the system matrix was generated for homogenous optical properties, when heterogeneity (62.98 cm^-1 variance in µ_s) was introduced to simulated phantoms, the results were still comparable (structural similarity homo: 0.67 ± 0.02 vs hetero: 0.66 ± 0.02).

中文翻译：

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次扩散角域荧光光学投影层析成像中迭代重建的基于模型的系统矩阵

这项工作涉及一种荧光光学投影层析成像系统，该系统用于低散射组织（如淋巴结），并具有对高散射光子的角域抑制作用。在这种情况下，已显示滤波反投影（FBP）图像重建可提供合理质量的图像，但是在此，将通过FBP获得的图像与使用Monte Carlo生成的系统矩阵进行的迭代图像重建之间的图像质量进行比较，可以证明迭代具有可衡量的改进方法。通过仿真和实验模型，在对比度和空间分辨率方面，迭代算法始终优于FBP。此外，当减少投影数量时，为了减少总成像时间，⁻³至0.66±0.02）; 虽然系统矩阵是为均匀的光学特性，所产生的异质性时（62.98厘米^-1方差μ_小号）引入到模拟幻影，结果仍然相当（结构相似HOMO：0.67±0.02 VS杂：0.66±0.02） 。