A Focus-of-Attention EM-ML Algorithm for PET Reconstruction
نویسندگان
چکیده
The EM{ML algorithm belongs to a family of algorithms that compute PET (positron emission tomography) reconstructions by iteratively solving a large linear system of equations. We describe a preprocessing scheme for focusing the attention, and thus the computational resources, on a subset of the equations and unknowns in order to reduce both the time and space requirements of such algorithms. The approach is completely data-driven and uses no prior anatomic knowledge. Experimental results are given for a CM{5 parallel computer implementation of the EM-ML algorithm using a simulated phantom as well as real data obtained from an ECAT 921 PET scanner.
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