A Grangeat-type half-scan algorithm for cone-beam CT.

Seung Wook Lee; Ge Wang

doi:10.1118/1.1562941

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A Grangeat-type half-scan algorithm for cone-beam CT.

Seung Wook Lee·Ge Wang

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Abstract

Modern CT and micro-CT scanners are rapidly moving from fan-beam toward cone-beam geometry. Half-scan CT algorithms are advantageous in terms of temporal resolution, and widely used in fan-beam and cone-beam geometry. While existing half-scan algorithms for cone-beam CT are in the Feldkamp framework, in this paper we compensate missing data explicitly in the Grangeat framework, and formulate a half-scan algorithm in the circular scanning case. The half-scan spans 180 degrees plus two cone angles that guarantee sufficient data for reconstruction of the midplane defined by the source trajectory. The smooth half-scan weighting functions are designed for the suppression of data inconsistency. Numerical simulation results are reported for verification of our formulas and programs. This Grangeat-type half-scan algorithm produces excellent image quality, without off-mid-plane artifacts associated with Feldkamp-type half-scan algorithms. The Grangeat-type half-scan algorithm seems promising for quantitative and dynamic biomedical applications of CT and micro-CT.

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Algorithms Brain Humans Imaging, Three-Dimensional Phantoms, Imaging Radiographic Image Enhancement Radiographic Image Interpretation, Computer-Assisted Reproducibility of Results Sensitivity and Specificity Tomography, Spiral Computed Comparative Study Evaluation Study Journal Article Research Support, U.S. Gov't, P.H.S.Validation Study

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Seung Wook Lee, Ge Wang. 2003. A Grangeat-type half-scan algorithm for cone-beam CT.. https://doi.org/10.1118/1.1562941

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