Corrections for accidental coincidences and attenuation in maximum-likelihood image reconstruction for positron-emission tomography.
Reconstruction procedures that account for attenuation in forming maximum-likelihood estimates of activity distributions in positron-emission tomography are extended to include regularization constraints and accidental coincidences. A mathematical model is used for these effects. The corrections are incorporated into the iterations of an expectation-maximization algorithm for numerically producing the maximum-likelihood estimate of the distribution of radioactivity within a patient. The images reconstructed with this procedure are unbiased and exhibit lower variance than those reconstructed from precorrected data.
Politte
D G
DG
Washington Univ., St. Louis, MO.
Snyder
D L
DL