I am principally interested in tomographic reconstruction for noise limited imaging modalities such as emission computed tomography (ECT), a modality which includes positron emission tomography (PET), single photon emission computed tomography (SPECT), and a new modality Compton SPECT. My activities in this and other tomographic areas have included statistical performance prediction and system optimization using Shannon's mutual information measure and generalizations of the Cramer-Rao bound; parametric shape modeling for object boundaries in ECT and NMR (nuclear magnetic resonance) imaging; image confidence region estimation based on projections; maximum likelihood image reconstruction via the EM algorithm and its variations. Some articles which I have recently co-authored appear below.

Journal Articles

Errata: The powers of 2 in the triangle inequalities on p.\ 1427 should not be there. Condition 2 should also include the requirement that \nabla^{10}\phi be continuous in \emph{both} arguments, i.e. in R_S \times R^p There should not be any 1/2 in the definition of J on p.\ 1426. The plus before the final quadratic form in (38) should be a minus.

Errata: The equation immediately below eqn. (18) is unnecessary. As written it suggests we foolishly replace some of the pixel estimates with "old" values, when of course we do not. The newer version that appears in our 1995 T-IP paper is correct, and supersedes the T-SP version. The proof of Theorem 2 incorrectly states that the eigenvalues of the Gauss-Siedel matrix are real. They can be complex, so the proof only applies to cases where the maximimum magnitude eigenvalue is real.

"Model-based estimation with boundary side information or boundary regularization [cardiac emission CT],"

"Model-based estimation for dynamic cardiac studies using ECT,"

"Information analysis of single photon computed tomography with count losses,"

"Information gain from count corrections in SPECT image reconstruction and classification,"

"The mutual information criterion for the design and evaluation of SPECT apertures,"

"Application of the mutual information criterion to assessing gamma cameras,"

Conference Proceeedings

"Uniform CR bound: implementation issues and applications to image reconstruction,"

"Bias-variance tradeoffs analysis using uniform CR bound for images"

"New complete-data spaces and faster algorithms for penalized-likelihood emission tomography,"

"Bias-variance tradeoffs analysis using uniform CR bound for a SPECT system,"

"Consistency set estimation for PET image reconstruction,"

"A fast recursive algorithm for computing CR-type bounds for image reconstruction problems,"

Prof. Alfred Hero III

Dept. of Electrical Engineering and Computer Science

The University of Michigan

1301 Beal Avenue

Ann Arbor, MI 48109-2122

Tel. (313) 763-0564

FAX: (313) 763-8041

WWW: http://www.eecs.umich.edu/~hero/hero.html

email: