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PubMed · 7391293

Split-filter computed tomography: a simple technique for dual energy scanning.

B Rutt·A Fenster
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Abstract

A simple technique for obtaining dual energy information from a single computed tomography (CT) scan is described. The method involves filtering the two halves of the X-ray fan beam differently. It is shown that during a 360 degree scan, this split-filtration geometry results in dual energy noise analysis, valid for polychromatic X-ray beams, is presented and used to determine the optimal parameters for the split-filter scans. Using the theoretically optimal split-filter design installed on a commercial CT scanner, photoelectric and Compton images of a head phantom were obtained. Recombination of the photoelectric and Compton components of attenuation at arbitrary energies demonstrates the ability to remove spectral artifacts from conventional CT images.

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CalibrationFiltrationModels, TheoreticalRadiation DosageRadiographic Image EnhancementTomography, X-Ray ComputedX-RaysJournal Article

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BibTeXRIS

B Rutt, A Fenster. 1980. Split-filter computed tomography: a simple technique for dual energy scanning.. https://doi.org/10.1097/00004728-198008000-00019

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