The expectation-maximization (EM) algorithm is an important tool for maximum-likelihood (ML) estimation and image reconstruction, especially in medical imaging. It is a non-linear iterative algorithmâ€¦ (More)

In an earlier paper we derived a theoretical formulation for estimating the statistical properties of images reconstructed using the iterative ML-EM algorithm. To gain insight into this complexâ€¦ (More)

We investigated the spatial resolution and quantitative properties of SPECT images reconstructed using filteredbackprojection (FB) and maximum likelihood-expectation maximization (ML-EM) algorithms.â€¦ (More)

We derive and discuss an algorithm for separating measurement-and null-space components of an object with respect to a given imaging system. This algorithm requires a discrete-to-discreteâ€¦ (More)

A theoretical formulation for characterization of SPECT (single photon emission computed tomography) image noise for a filtered-backprojection reconstructed image was derived. The formulation takesâ€¦ (More)