Title :
Comparison between ML-EM and WLS-CG algorithms for SPECT image reconstruction
Author :
Tsui, Benjamin M W ; Zhao, Xide ; Frey, Eric C. ; Gullberg, Grant T.
Author_Institution :
Dept. of Radiol., North Carolina Univ., Chapel Hill, NC, USA
fDate :
12/1/1991 12:00:00 AM
Abstract :
The properties of the maximum likelihood with expectation maximization (ML-EM) and the weighted least squares with conjugate gradient (WLS-CG) algorithms for use in compensation for attenuation and detector response in cardiac SPECT imaging were studied. A realistic phantom, derived from a patient X-ray CT study to simulate 201Tl SPECT data, was used in the investigation. In general, the convergence rate of the WLS-CG algorithm is about ten times that of the ML-EM algorithm. Also, the WLS-CG exhibits a faster increase in image noise at large iteration numbers than the ML-EM algorithm
Keywords :
cardiology; computerised picture processing; computerised tomography; medical diagnostic computing; radioisotope scanning and imaging; ML-EM; WLS-CG; attenuation; cardiac SPECT imaging; compensation; convergence rate; detector response; maximum likelihood with expectation maximization; patient X-ray CT study; weighted least squares with conjugate gradient; Attenuation; Bayesian methods; Biomedical measurements; Detectors; Gaussian noise; Image reconstruction; Iterative algorithms; Least squares methods; Maximum likelihood detection; Reconstruction algorithms;
Journal_Title :
Nuclear Science, IEEE Transactions on
