论文标题
使用基于多光子邮票的时间步行校正：蒙特卡洛研究
Near 65ps-fwhm in 20mm-LSO TOF-PET by using a time walk correction based on multi-photon stamps: a Monte Carlo study
论文作者
论文摘要
目的：调查从晶体光共享和多光子时间邮票中得出的时间步行评估是否可以改善TOF分辨率。 方法：对SIPM（FBK-NUV-HD）进行了蒙特卡洛模拟，并与常规的4x4 mm2像素化LSO（0.2％CA：CE）耦合，并耦合到8x4 mm2 pixelated LSO，三角形光学窗口在其中允许在两个4x4 mm2 subpixels the Doi上共享三角形光窗口。时间步行估计被建模为doi相对于光子检测顺序中时间差的加权总和。为了获得最佳的TOF分辨率，优化了依赖DOI的权重。 结果：观察到两个4x4 mm2子像素之间的光共享的强线性DOI依赖性。 4x4x20 mm3 LSO的TOF分辨率分别为99.7，81.2，66.4 ps-fwhm而无需进行任何校正，并进行DOI校正和依赖DOI依赖的时间步行校正。时间步行校正是从序列（2 ** k）光子的7个时间戳中得出的，k在[0,6]内。 结论：可以从光子时间检测序列估算光子时间步行，并可以与DOI评估相结合以改善TOF分辨率。
Aim: Investigate whether a time walk assessment derived from crystal light sharing and multi-photon time stamps can improved the TOF resolution. Method: Monte Carlo simulations were performed for SiPM (FBK-NUV-HD) coupled to conventional 4x4 mm2 pixelated LSO (0.2%Ca:Ce ) and also coupled to 8x4 mm2 pixelated LSO in which a triangular optical window allows light sharing between the two 4x4 mm2 sub-pixels depending on the DOI. A time walk estimation was modelled as a DOI dependent weighted sum of the time differences within the photons detection sequence. The DOI dependent weights were optimized in order to get the best TOF resolution. Results: A strong linear DOI dependence of the light sharing between the two 4x4 mm2 sub-pixels was observed. The TOF resolutions for a 4x4x20 mm3 LSO were 99.7, 81.2, 66.4 ps-fwhm without any correction, with DOI correction and with DOI dependent time walk correction, respectively. The time walk correction was derived from the 7 time stamps of the (2**k )th photons in the sequence, with k within[0,6]. Conclusion: photon time walk can be estimated from the photon time detection series and can be advantageously combined with the DOI assessment to improve TOF resolution.
