We have developed a preclinical rabbit cardiac SPECT system by re-engineering a classical clinical SPECT scanner with state-of-the-art electronics and control systems. Notable features include digital waveform capture of the time-dependent outputs of the photomultiplier tubes (PMT). The digitization of the scintillation pulses allows for the incorporation of the entire waveform into the maximum-likelihood estimation (MLE) of event parameters (x, y, energy, etc.), rather than one scalar (i.e. integrated current). We present here details of the waveform-inclusive MLE, the measurements of the mean-detector-response functions, and the determination of the point spread function, along with the associated acceleration via graphics-processor-unit (GPU) programming. Additionally, calibration algorithms of the system are discussed.
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