Design of a prototype real-time image reconstruction system for PET imaging

Real-time reconstruction of the acquired data in positron emission tomography (PET) imaging would facilitate positioning of the subject and could serve to monitor image quality and detect potential problems during the acquisition. A real-time image reconstruction prototype was developed as an extension of the data acquisition system of the Sherbrooke Animal PET scanner using a network of field programmable gate arrays (FPGA), digital signal processors (DSP) and a fast PET image reconstruction algorithm based on SVD decomposition of the system matrix. Two different implementation of the reconstruction system were investigated in order to obtain the fastest reconstruction times for images of at least 64×64 pixels. Initial results demonstrate that the acquired image can be updated every second using a 600 MHz personal computer for the reconstruction calculations while using the DSPs to pre-process the incoming data.