Skip to Main Content
Iterative algorithms are of interest for both positron-emission tomography (PET) and single-photon-emission computed tomography (SPECT) because they permit accurate modeling of the imaging system, and they can be derived to satisfy certain statistical performance criteria. The convergence process, however, is influenced by the object distribution and noise level, so that different algorithms demonstrate a wide range of convergence phenomena. This object dependence is described for two widely accepted image-reconstruction algorithms; ART and maximum-likelihood estimation.
Date of Publication: Feb 1988