基于参考组分的双能CT成像方法

Dual-energy CT Imaging Method Based on Reference Components

双能CT材料分解对了解物质内部材料分布有重要作用,常规CT所使用的X射线能谱分布未知,无法根据能量信息获得材料衰减系数,并且连续能谱投影与单能重建算法不匹配,导致重建图像衰减系数和材料理论衰减系数之间存在误差,分解结果不准确。针对上述问题,本文引入参考组分获得等效能量信息,进而获得材料的单能衰减系数,并且引入邻域空间欧式距离容差对材料分解模型中的材料组成进行约束,欧氏距离容差根据参考组分重建图像获取。实验结果表明,本文方法能够在常规CT投影系统的基础上,对检测物体中各材料进行准确分解。

The material decomposition of dual-energy CT plays an important role in understanding the material distribution inside the substance.The X-ray energy spectrum distribution used in conventional CT is unknown,and the material attenuation coefficient cannot be obtained from the energy information,and the continuous energy spectrum projection does not match the single-energy reconstruction algorithm.There is an error between the attenuation coefficient of the reconstructed image and the theoretical attenuation coefficient of the material,and the decomposition result is not accurate.To solve the above problems,this paper introduces reference components to obtain equivalent energy information,and then obtains the single energy attenuation coefficient of the material,and introduces the Euclidean distance in the neighborhood space the tolerance restricts the material composition in the material decomposition model,and the Euclidean distance tolerance is obtained from the reconstructed image of the reference component.The experimental results show that the method in this paper can accurately decompose the materials in the detected object on the basis of the conventional CT projection system.