Iterative reconstruction of electronically collimated SPECT images

A two-sage approach for the tomographic reconstruction of single-photon electronically collimated images has been implemented using either ART (algebraic reconstruction technique) or the MLE (maximum likelihood estimator) for the first stage, in which cone beam projections are reconstructed from coincident count data, and a convolution backprojection method for the second stage, in which tomographic images are reconstructed from the estimated cone beam images. The performance of ART and MLE has been compared based on the final tomographic reconstructions for simulated and experimental studies. The results indicate an enhancement of the resolution in the reconstructed images for MLE