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PubMed · 15551605

Implementation of an accelerated iterative algorithm for cone-beam SPECT.

J Li·R J Jaszczak·K L Greer·R E Coleman
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Abstract

In this paper we describe the implementation of an accelerated iterative reconstruction algorithm (AIRA) for cone-beam (CB) projections using a single circular orbit in single-photon-emission computed tomography (SPECT). This algorithm is a modified maximum-likelihood-expectation-maximization (ML-EM) algorithm and several approaches have been used to accelerate the reconstruction process. These approaches include: (i) the use of ordered subsets; (ii) the use of active areas and volumes; and (iii) the storing in memory of the transition vector for a given ray (during the forward projection step). This algorithm, which compensates for collimator geometric sensitivity variation as a function of position and makes uniform attenuation corrections has been evaluated using experimentally acquired phantom data. The results demonstrate a two-orders-of-magnitude decrease of the computational time of this algorithm over the conventional ML-EM algorithm with similar convergence properties.

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AlgorithmsArtifactsHumansImage Processing, Computer-AssistedLikelihood FunctionsModels, StatisticalPhantoms, ImagingPhotonsSensitivity and SpecificitySoftwareTomography, Emission-Computed, Single-PhotonJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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J Li, R J Jaszczak, K L Greer, R E Coleman. 1994. Implementation of an accelerated iterative algorithm for cone-beam SPECT.. https://doi.org/10.1088/0031-9155%2F39%2F3%2F025

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