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双弧源轨迹锥束CT的三维图像重建
In this paper, we review the general theory and algorithms that have proposed for image reconstruction from cone-beam data for general trajectories with kinks. The reconstruction algorithms include the backprojection filtration (BPF) algorithm and the minimum-data filteredbackprojection (MD-FBP) algorithm. One of the unique features of these new algorithms is that they can reconstruct exactly images within regions of interest (ROIs) from data containing truncations. In this work, we also apply these algorithms to reconstructing ROI images from truncated data acquired with a trajectory consisting of two pieces of arcs, which is referred to as the arc-arc trajectory. The numerical results in these studies show that exact ROI images can be reconstructed by use of the BPF and MD-FBP algorithms from truncated data acquired with an arc-arc trajectory.
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另一种基于弦的锥束CT图像重建的推导方法
Recently, we have developed a new formula for cone-beam CT image reconstruction. From the formula, we have also derived three algorithms. Two of the algorithms, which are referred to as the back-projection filtration (BPF) and minimum-data filtered backprojection (MD-FBP) algorithms, can provide volume images from projection data with a minimal scanning arc and minimal irradiation per view angle. The fact that these reconstruction algorithms allow for minimum irradiation per view is unique to the BPF and MD-FBP algorithms. This article explores the mathematical relationship between the projection data and an intermediate back-projection image necessary for obtaining the actual volume image. An alternative proof of the formula and the BPF algorithm are also provided.
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鞍形CT的感兴趣区图像重建
Recently, we have developed a general formula for 3D cone-beam CT reconstruction, which can accommondate general, smooth trajectories. From the formula, algorithms can be derived for image reconstruction within a region of interest (ROI) from truncated data. In this work, we apply the derived backprojection filteration (BPF) algorithm and the minimum-data filtered backprojection (MD-FBP) algorithm to reconstructing ROI images from cone-beam projection data acquired with a saddle trajec-tory. Our numerical results in these studies demonstrate that the BPF and MD-FBP algorithms can accurately reconstruct ROI images from truncated data.
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在锥束CT中基于弦的边缘图像重建
In this work, we demonstrate that the theory of cone-beam tomography image reconstruction on chords can be modified for use with local tomography problems. Our analysis reveals that discontinuities in the profiles of the object function along chords can be reconstructed readily. By consideration of all possible chords, an image that de-scribes the location of boundaries within an object can be reconstructed. A preliminary numerical study is conducted to validate and demonstrate the reconstruction method.
