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Cone-beam CT from width-truncated projections.

P S Cho·A D Rudd·R H Johnson
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Abstract

In this paper we report cone-beam CT techniques that permit reconstruction from width-truncated projections. These techniques are variants of Feldkamp's filtered backprojection algorithm and assume quasi-redundancy of ray integrals. Two methods are derived and compared. The first method involves the use of preconvolution weighting of the truncated data. The second technique performs post-convolution weighting preceded by non-zero estimation of the missing information. The algorithms were tested using the three-dimensional Shepp-Logan head phantom. The results indicate that given an appropriate amount of overscan, satisfactory reconstruction can be achieved. These techniques can be used to solve the problem of undersized detectors.

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AlgorithmsComputer SimulationPhantoms, ImagingRadiographic Image EnhancementTomography, X-Ray ComputedJournal ArticleResearch Support, Non-U.S. Gov't

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P S Cho, A D Rudd, R H Johnson. Cone-beam CT from width-truncated projections.. https://doi.org/10.1016/0895-6111(96)00031-6

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