XFCT is a novel method for early cancer detection. Increasing concentration of contrast agents and incident X-rays’ energy were used to improve detecting accuracy, which greatly increased the prevalence of Contrast-induced nephropathy. Therefore, this research explores the adaptive contrast agents and uses Geant4 to simulate the imaging conditions of Pt, Bi, Gd, Ru, and Au for searching the lowest detectable concentration based on the proposed fast multi-pinhole collimated XFCT (fmpc-XFCT)imaging system and low incident energy. Several imaging parameters including pinhole radius(0.7mm, 0.8mm and 1mm) were adjusted, the optimized EM-TV algorithm were used to reconstruct XFCT images. It is found that Bi element is superior to other metal elements in terms of Contrast to Noise Ratio(CNR) and fluorescence efficiency, the lowest concentration can be detected is 0.12% with optimal parameters.

中文翻译：

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带光子计数探测器的X射线荧光CT潜在造影剂的模拟研究

XFCT 是一种用于早期癌症检测的新方法。通过增加造影剂浓度和入射X射线能量来提高检测精度，大大增加了造影剂肾病的患病率。因此，本研究探索自适应造影剂并使用 Geant4 模拟 Pt、Bi、Gd、Ru 和 Au 的成像条件，以基于所提出的快速多针孔准直 XFCT (fmpc-XFCT) 成像搜索最低可检测浓度系统和低入射能量。调整针孔半径（0.7mm、0.8mm、1mm）等多个成像参数，采用优化后的EM-TV算法重建XFCT图像。发现Bi元素在对比度（CNR）和荧光效率方面优于其他金属元素，