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Correction for beam hardening in computed tomography.

P K Kijewski·B E Bjärngard
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Abstract

Corrections for beam-hardening artifacts in computed tomography can be made by using a model which assumes that water and bone mineral are the only constituents of tissue. With this model, a correction factor for the measured transmission values can be calculated such that the reconstructed attenuation coefficients have values corresponding to a monoenergetic source of known energy. Systematic errors in the uncorrected attenuation coefficients, which may be 5%, can be reduced to less than 1% if corrected transmission values are used.

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Body WaterBone and BonesHumansMineralsModels, TheoreticalRadiation DosageStatistics as TopicTomography, X-Ray ComputedJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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P K Kijewski, B E Bjärngard. Correction for beam hardening in computed tomography.. https://doi.org/10.1118/1.594429

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