Practical cone-beam lambda tomography.

Hengyong Yu; Yangbo Ye; Ge Wang

doi:10.1118/1.2348767

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PubMed · 17089830

Practical cone-beam lambda tomography.

Hengyong Yu·Yangbo Ye·Ge Wang

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Abstract

As a potentially important technology for medical x-ray computed tomography (CT), lambda tomography (LT) is to reconstruct a gradient-like image only from local projection data. Based on our recently derived exact fan-beam LT formula, [H. Y. Gu and G. Wang, Int. J. Biomed. Imaging 2006(1), 1-9 (2006)] here we propose a practical cone-beam LT algorithm for LT reconstruction from local data collected along an arbitrary smooth three-dimensional curve. A key step in our algorithm is to determine an appropriate vector perpendicular to the line connecting the x-ray source and an image point. The algorithm is implemented assuming an equispatial planar detector and a nonstandard spiral trajectory. The numerical simulation results demonstrate the merits of our method.

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Algorithms Computer Simulation Computers Humans Models, Statistical Radiographic Image Interpretation, Computer-Assisted Radiography, Thoracic Reproducibility of Results Sensitivity and Specificity Tomography, Spiral Computed Tomography, X-Ray Computed X-Rays Journal Article Research Support, N.I.H., Extramural

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Hengyong Yu, Yangbo Ye, Ge Wang. 2006. Practical cone-beam lambda tomography.. https://doi.org/10.1118/1.2348767

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