Development of a new brain PET scanner based on single event data acquisition

A new brain PET scanner based on single event data acquisition with on-the-fly coincidence detection has been developed. The new scanner was designed to form a detector ring of 430 mm in diameter with 32 detector modules. The single event data generated at each detector module were transferred to the data acquisition system through a fiber cable. The single event data from all detector modules were merged and processed to create coincidence event data in software with on-the-fly. The validation results indicated that the single count rate capability was expected over 220 Mcps. At experiments using ¹⁸F radioisotopes, the maximum single count rate was approximately 20 Mcps, and the maximum coincidence count rate with prompt was obtained 3.2 Mcps. The system timing resolution was 2.6 ns FWHM, and the optimum coincidence time window was 4.3 ns, obtained by adjusting the timing delay variations between each detector module.