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Correction for beam hardening in computed tomography.

G T Herman
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Abstract

We investigate how one can estimate from the total attenuation, p, of a polyenergetic X-ray beam what the total attenuation, m, of a monoenergetic beam would have been along the same ray. We find that for beams with typical diagnostic X-ray spectra passing through the human body one can find a simple function f such that f(p) is a sufficiently close estimate of m to allow good reconstructions. We also find that m cannot be accurately estimated from p based on the assumption that the human body consists of water alone. Our results are demonstrated by reconstructions of a mathematical model of a cross-section of the human thorax. This article is self-contained and includes in its Appendices a detailed discussion of the mathematical nature of the problem of bean hardening in computed tomography.

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HumansMathematicsModels, StructuralRadiography, ThoracicTomography, X-Ray ComputedJournal Article

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BibTeXRIS

G T Herman. 1979. Correction for beam hardening in computed tomography.. https://doi.org/10.1088/0031-9155%2F24%2F1%2F008

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