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EnPiT: filtered back-projection algorithm for helical CT using an n-Pi acquisition.

Claas Bontus·Thomas Köhler·Roland Proksa
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Abstract

In this paper, we formulate a reconstruction algorithm for an n-Pi acquisition, where n can be any positive odd integer. The algorithm is a generalization of the method presented in (Bontus et al. 2003). It is based on the results obtained by Katsevich (2004). For the algorithm, different sets of filter-lines have to be defined. We describe the variation of these lines along the detector in some detail, before we discuss, how the method gives all Radon-plane contributions the correct weighting. The different sets of filter-lines are all contained within the n-Pi window, such that a practical realization is possible. Reconstruction results, which we present in the final section, show convincing image quality.

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AlgorithmsArtificial IntelligenceBrainHumansImaging, Three-DimensionalNumerical Analysis, Computer-AssistedPhantoms, ImagingRadiographic Image EnhancementRadiographic Image Interpretation, Computer-AssistedReproducibility of ResultsSensitivity and SpecificitySignal Processing, Computer-AssistedTomography, Spiral ComputedEvaluation StudyJournal Article

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Claas Bontus, Thomas Köhler, Roland Proksa. 2005. EnPiT: filtered back-projection algorithm for helical CT using an n-Pi acquisition.. https://doi.org/10.1109/tmi.2005.850545

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