非对称散射核法去除锥形束CT计算机图像散射伪影

AFast Algorithm for Removing Scattering Artifacts from Cone Beam CT Images

为去除锥形束CT计算机图像散射伪影,提出一种基于非对称笔形束核的散射反卷积去除算法,该算法采用MC模拟获取适应CT几何结构下的笔形束散射非对称数据,利用线性拟合算法对非对称核进行建模和拟合,通过计算机GPU实现基于拟合非对称散射核的快速运算从而实现快速的CT图像散射伪影校正。实验结果表明:该方法可以在5 s内实现图像非一致性从15%下降至5%以下,该方法可以适用于临床应用。

In medical computer image,cone beam CT image is widely welcomed because of its low radiation dose and high spatial resolution.However,due to the scattering characteristics of photon particles,there are natural scattering artifacts in the computer image of cone beam CT.In order to remove the artifacts by computer image processing,a deconvolution algorithm based on asymmetric pencil beam kernel is proposed in this paper.Firstly,the asymmetric data of pencil beam scattering which adapts to CT geometry is established by MC simulation and then the asymmetric kernel is modeled and fitted by linear fitting method.Finally,the algorithm is realized by GPU The fast operation of scattering kernel can realize fast CT image artifact processing and enhance the resolution and contrast of image.