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PubMed · 9572499

Iterative reconstruction for helical CT: a simulation study.

J Nuyts·B De Man·P Dupont·M Defrise·P Suetens·L Mortelmans
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Abstract

Iterative reconstruction algorithms for helical CT are presented. The algorithms are derived from two-dimensional reconstruction algorithms, by adapting the projector/backprojector to the helical orbit of the source, and by constraining the axial frequencies with a Gaussian sieve. Simulations have been carried out and the performance of the iterative algorithms is compared to that of filtered backprojection of synthetic (interpolated) two-dimensional sinograms. The iterative algorithms produce superior bias-noise curves. Axial resolution is superior, but disturbing edge-artefacts are introduced.

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AlgorithmsArtifactsCalibrationComputer SimulationHumansImage Processing, Computer-AssistedLikelihood FunctionsPhantoms, ImagingTomography, X-Ray ComputedJournal ArticleResearch Support, Non-U.S. Gov't

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J Nuyts, B De Man, P Dupont, M Defrise, P Suetens, L Mortelmans. 1998. Iterative reconstruction for helical CT: a simulation study.. https://doi.org/10.1088/0031-9155%2F43%2F4%2F003

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