First experimental proof of PET imaging based on multi-anode MCP-PMTs with Cherenkov radiator-integrated window

Objective. Achieving a higher signal-to-noise ratio (SNR) gain or direct positron emission imaging (dPEI) by improving the coincidence time resolution (CTR) of time-of-flight positron emission tomography (TOF-PET) systems is paramount for many advanced clinical PET imaging applications. This places greater demands on the timing performance of all PET system components. Approach. An effective method for enhancing detector time resolution is to use microchannel plate photomultiplier tubes (MCP-PMTs) for prompt Cherenkov photon detection. In this study, we developed a dual-module PET imaging experimental platform. This platform uses two 8 × 8-anode Cherenkov radiator-integrated window MCP-PMTs, which was developed in-house. It also uses multi-channel electronics system, which was also developed in-house. We designed specific calibration and correction methods for the platform to meet the experimental requirements. Main results. Based on this dual-module platform, a total FWHM of 203.6 ps (σ = 86.5 ps) was achieved. Multi-component analysis of the time spectrum was performed based on the interaction positions of annihilation photon pairs in different coincidence events. Imaging experiments were conducted using various types of radiation sources and phantoms. Spatial resolution was evaluated, confirming the platform's ability to distinguish 4 mm spots in Derenzo-like phantoms. Furthermore, preliminary improvements in image quality were verified when incorporating TOF information into the dual-module platform. Significance. In this study, we achieved the first experimental verification of module-level PET imaging based on the detection of Cherenkov light. This has overcome the limitations of single-pixel detectors in previous related research and reduced the radiation dose and acquisition time required for imaging by nearly 10 times. Additionally, this study evaluated the potential of a dual-module platform for achieving higher temporal performance and direct imaging, elucidated the importance of developing PbF2 integrated window multi-anode MCP-PMTs, and provided experimental evidence for future performance enhancements in Cherenkov light detection-based PET systems.