An Accurate Timing Alignment Method with Time-to-Digital Converter Linearity Calibration for High-Resolution TOF PET.
An Accurate Timing Alignment Method with Time-to-Digital Converter Linearity Calibration for High-Resolution TOF PET.
复制标题
一种用于高分辨率 TOF PET 的具有时间数字转换器线性校准的精确定时对准方法。
DOI：
10.1109/tns.2015.2430751
复制
发表时间：
2015
影响因子：
1.8
通讯作者：
Wong,Wai-Hoi
中科院分区：
文献类型：
--
作者：
Li,Hongdi;Wang,Chao;An,Shaohui;Lu,Xingyu;Dong,Yun;Liu,Shitao;Baghaei,Hossain;Zhang,Yuxuan;Ramirez,Rocio;Wong,Wai-Hoi
Accurate PET system timing alignment minimizes the coincidence time window and therefore reduces random events and improves image quality. It is also critical for time-of-flight (TOF) image reconstruction. Here, we use a thin annular cylinder (shell) phantom filled with a radioactive source and located axially and centrally in a PET camera for the timing alignment of a TOF PET system. This timing alignment method involves measuring the time differences between the selected coincidence detector pairs, calibrating the differential and integral nonlinearity of the time-to-digital converter (TDC) with the same raw data and deriving the intrinsic time biases for each detector using an iterative algorithm. The raw time bias for each detector is downloaded to the front-end electronics and the residual fine time bias can be applied during the TOF list-mode reconstruction. Our results showed that a timing alignment accuracy of better than ±25 ps can be achieved, and a preliminary timing resolution of 473 ps (full width at half maximum) was measured in our prototype TOF PET/CT system.
