The research team led by Professor Zheng Gu from the Institute of Biomedical Engineering of Shenzhen Bay Laboratory, in collaboration with Professor Yongfeng Yang's group from the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, has successfully published a paper titled Comparison of Timing Measurement Methods of Dual-Ended Readout Scintillator Array PET Detectors in the prestigious journal IEEE Transactions on Radiation and Plasma Medical Sciences. This study investigates the optimization of time resolution for dual-ended readout PET detectors with depth-of-interaction (DOI) capability, comparing the best time resolutions achieved using scintillator arrays of various sizes and surface treatments. 

For scintillator arrays with dimensions of 3.10×3.10×20 mm³ and an ESR reflector, the optimal time resolution achieved was 234 ps. When using a BaSO₄ reflector with the same array size, the time resolution was 239 ps, and for a smaller 1.88×1.88×20 mm³ array with a BaSO₄ reflector, the resolution reached 275 ps. Compared to traditional single-ended readout detectors, the dual-ended readout detector developed in this study not only provides high 3D spatial resolution but also significantly enhances time resolution, making it suitable for the development of future clinical PET systems with high spatial resolution, high sensitivity, and high time resolution.

In this study, we conducted experiments on three different PET detector configurations, varying in scintillator size, surface treatment, and reflector type, to analyze their crystal decoding, energy resolution, DOI resolution, and time resolution in detail. The experimental setup is illustrated in Figure 1. To further optimize time resolution, we systematically compared various timing algorithms for dual-ended readout detectors for the first time. These algorithms include timing based on the signal from only the front or rear end, selecting the faster signal between the two ends, averaging the timing from both ends, averaging after DOI correction, and using DOI-corrected energy-weighted timing from the two fastest signals at both ends.

Experimental results showed that all three detectors achieved clear crystal decoding, high DOI resolution, and excellent time-of-flight (TOF) time resolution. Ultimately, the energy-weighted DOI-corrected dual-ended timing algorithm achieved the best time resolution.

This study successfully developed a dual-ended readout PET detector that features high spatial resolution, high DOI resolution, high TOF time resolution, and high detection efficiency, laying a solid foundation for the development of next-generation high-performance clinical PET systems.

Source Information:

Comparison of Timing Measurement Methods of Dual-Ended Readout Scintillator Array PET Detectors