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PubMed · 2294555

Single-exposure dual-energy computed radiography: improved detection and processing.

D L Ergun·C A Mistretta·D E Brown·R T Bystrianyk·W K Sze·F Kelcz·D P Naidich
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Abstract

Recent reports have emphasized the potential for dual-energy computed radiographic applications. An improved method for single-exposure material-selective imaging with a photostimulable phosphor computed radiography system was investigated. The essential elements of the technique are (a) prefiltration with gadolinium, which divides the incident broad-beam x-ray spectrum into low-energy and high-energy peaks; (b) a cassette consisting of four photostimulable phosphor plates that record images of increasing mean energies, with a computed energy separation of 23 keV from the front to the rear plate; (c) spatially dependent scatter and beam-hardening corrections; and (d) a noise-reduction algorithm based on noise correlations between bone-selective and soft-tissue-selective dual-energy images. These elements result in improved material cancellation and signal-to-noise ratio throughout the image.

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AlgorithmsHumansRadiography, Dual-Energy Scanned ProjectionTechnology, RadiologicTomography, X-Ray ComputedJournal Article

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D L Ergun, C A Mistretta, D E Brown, R T Bystrianyk, W K Sze, F Kelcz, D P Naidich. 1990. Single-exposure dual-energy computed radiography: improved detection and processing.. https://doi.org/10.1148/radiology.174.1.2294555

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