基于能谱分离的变能量X射线多谱CT成像方法研究

项目名称： 基于能谱分离的变能量X射线多谱CT成像方法研究

项目编号： No.61301259

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 陈平

作者单位： 中北大学

项目金额： 28万元

中文摘要： X射线多谱成像相对于单能谱成像，其能谱信息更丰富，可依据能谱与衰减系数的多谱对应性，实现检测对象微观信息的定性与定量检测。而在多谱成像中，光子计数型探测器具有独特的优势，可直接在数据接收端实现能谱分离与解析，但是由于价格昂贵、承受能量峰值小、分离能级受限等，无法工程化应用。为此项目针对现有在役CT系统，在不改变CT系统物理组成的基础上，利用射线滤波和变能量成像技术，研究一种等效的多谱信息获取方法- - 射线发射端能谱分离。其次，针对其特殊性，耦合变能量多谱成像先验，研究基于能谱分离的变能量X射线多谱CT重建算法，并通过能谱评估与补偿，实现物理层面上的多谱成像。本项目的研究可揭示成像系统与多谱CT的物理对应关系，确保多谱成像的物理表征正确性，促进多谱成像及定量检测技术的发展；同时极大地拓展在役CT系统的硬件潜能，使现有在役CT系统具备多谱CT功能。

中文关键词： 多能CT；能谱分离；能谱匹配；变能量；物理约束

英文摘要： For X-ray single-energy imaging, the energy spectrum information of X-ray multi-spectrum imaging is more abundant. Based on the multi-spectrum congruity between energy spectrum and attenuation coefficient, multi-spectrum fusion can realize qualitative and quantitative detection for the micro information of the testing object. However in multi-spectrum imaging, the photon-counting detector has special superiority. It can realize spectrum separation and resolving in the data collection. But because of the higher price, the less energy peak bearing, and the restriction of separation level, this detector can't apply to engineering. So based on no-change the physical composition of imaging system，using ray filtering and varying energy imaging, the project will research an equivalent method of multi-spectrum information acquisition, which is the spectrum separation at the ray emission. Then for its specificity, by coupling the priori of varying energy multi-spectrum imaging, research the reconstruction algorithm of X-ray multi-spectrum CT based spectrum separation. Also by energy estimate and compensation, the physical level multi-spectrum imaging will be realized. This project can reveal the corresponding relationship between imaging system and multi-spectrum CT, ensure the correctness of physical characterization ab

英文关键词： Multi-energy CT；Energy Spectrum Separation；Energy Spectrum Matching；Varying Energy；Physical Restriction