title: An Accurate Timing Alignment Method with Time-to-Digital Converter Linearity Calibration for High-Resolution TOF PET.
abstract: 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.
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Hongdi
authors.initials: H
authors.lastname: Li
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Shaohui
authors.initials: S
authors.lastname: An
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Xingyu
authors.initials: X
authors.lastname: Lu
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Dong
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Shitao
authors.initials: S
authors.lastname: Liu
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Hossain
authors.initials: H
authors.lastname: Baghaei
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Yuxuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Rocio
authors.initials: R
authors.lastname: Ramirez
authors.affiliation: H. Baghaei, Y. Zhang, R. Ramirez and W.-H. Wong are with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. H. Li, S. An, C. Wang and S. Liu were with The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; they are now with UIH, Shanghai, China. X. Lu and Y. Dong are with UIH, Shanghai, China.
authors.forename: Wai-Hoi
authors.initials: WH
authors.lastname: Wong
keywords: Positron emission tomography (PET); Time-of-flight (TOF); Time-to-digital converter (TDC) nonlinearity; Timing alignment