title: On Bayesian image reconstruction from projections: uniform and nonuniform a priori source information.
abstract: A method that incorporates a priori uniform or nonuniform source distribution probabilistic information and data fluctuations of a Poisson nature is presented. The source distributions are modeled in terms of a priori source probability density functions. Maximum a posteriori probability solutions, as determined by a system of equations, are given. Interactive Bayesian imaging algorithms for the solutions are derived using an expectation maximization technique. Comparisons of the a priori uniform and nonuniform Bayesian algorithms to the maximum-likelihood algorithm are carried out using computer-generated noise-free and Poisson randomized projections. Improvement in image reconstruction from projections with the Bayesian algorithm is demonstrated. Superior results are obtained using the a priori nonuniform source distribution.
authors.affiliation: Dept. of Radiol., Duke Univ. Med. Center, Durham, NC.
authors.forename: Z
authors.initials: Z
authors.lastname: Liang
authors.forename: R
authors.initials: R
authors.lastname: Jaszczak
authors.forename: K
authors.initials: K
authors.lastname: Greer