扇束CT重建图像的几何伪影分析

基金项目:

国家自然科学基金资助项目(60971131)；北京市高层次人才资助项目(RHR20110509)

详细信息

Analysis of Geometric Artifacts for Fan-Beam CT

摘要: 实际工业CT系统在机械安装时很难满足经典CT图像重建公式所要求的几何对准关系。当不满足该几何对准关系时，利用经典CT重建公式重建的图像将出现几何伪影，从而影响对CT图像的判读。针对扇束CT扫描系统，研究了几何参数误差对一根细丝断层图像的影响，导出了描述细丝断层图像伪影形态的包络线方程，并基于包络线给出了几何伪影的形态分类、演化规律和性质，同时给出了几何参数误差的调整方法。
- 扇束CT /
- 图像重建 /
- 参数误差 /
- 伪影分析
Abstract: It is very difficult to modulate a real industrial CT system to satisfy the geometric alignment relations required by the conventional CT image reconstruction formula. A misalignment will result in geometric artifacts in the image reconstructed by the conventional formula, which may cause a misjudgment. In this paper, we study the impact of geometric parameters errors for fan-beam system on the reconstructed images of a thin wire. We derive the envelope function which describes geometric artifact configuration in the image. Based on the envelope function, we give a classification, the evolution regularity and the characteristics of geometric artifacts. Besides, we give a method to adjust the errors of geometric parameters.
- Fan-beam CT /
- Image Reconstruction /
- Parameters error /
- Artifacts analysis

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