一种X射线射束硬化校正方法

A Correction Method of X-ray Beam Hardening

在医学CT成像系统中,X射线源发出的X射线是多能的,若直接对其进行传统方法的重建,会导致射束硬化,使重建的图像出现“杯状”或“条状”伪影,降低图像质量,干扰诊断等问题,因此需要对CT硬化伪影进行校正。本文提出了一种射束硬化伪影的校正方法,利用近似材料衰减系数与x射线能量的关系,通过从原始重建图像中减去伪影图像来获得校正后的图像。该方法不需要先验知识。数值实验表明,该方法能有效、快速地校正射束硬化伪影。

In the medical CT imaging system,the X-ray from the X-ray source is multi-functional,If we directly reconstruct it with traditional methods,it will lead to beam hardening,make the reconstructed image appear"Cup"or“strip”artifacts,reduce image quality,interfere with diagnosis and other problems,so we need to correct CT hardening artifacts.In this paper,a correction method of beam hardening artifacts is proposed.The corrected image is obtained by subtracting the artifacts from the original reconstructed image by using the relationship between the approximate material attenuation coefficient and the X-ray energy.This method does not need prior knowledge.Numerical experiments show that this method can correct beam hardening artifacts effectively and quickly.