Noise and Edge Artifacts in Maximum-Likelihood Reconstructions for Emission Tomography

  title={Noise and Edge Artifacts in Maximum-Likelihood Reconstructions for Emission Tomography},
  author={D. Snyder and M. Miller and L. J. Thomas and D. Politte},
  journal={IEEE Transactions on Medical Imaging},
Images produced in emission tomography with the expectation-maximization algorithm have been observed to become more noisy and to have large distortions near edges as iterations proceed and the images converge towards the maximum-likelihood estimate. It is our conclusion that these artifacts are fundamental to reconstructions based on maximum-likelihood estimation as it has been applied usually; they are not due to the use of the expectation-maximization algorithm, which is but one numerical… Expand
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