摘要
提出了一种CT去金属伪影的自适应衰减滤波混合算法。它先对金属区域投影数据进行自适应衰减和滤波,通过滤波反投影(FBP)重建图像,再利用原始投影数据对金属区域进行最大期望值(EM)重建,最后根据迭代重建的结果,对衰减和滤波后重建的图像中的金属区域进行补偿。仿真结果表明,该算法能有效去除条状伪影,完整地呈现金属物体的结构,并能保证金属物体周围的组织不失真。算法的计算复杂度较小,而且对包含多个金属物体的CT图像效果也较好。
A new adaptively hybrid filtering algorithm is proposed to reduce the artifacts caused by metal in CT image. Firstly, the method is used to preprocess the projection data of metal region and is reconstruct by filtered back projection （FBP） method. Then the expectation maximization algorithm （EM） is performed on the iterative original metal project data. Finally, a compensating procedure is applied to the reconstructed metal region. The simulation result has demonstrated that the proposed algorithm can remove the metal artifacts and keep the structure information of metal object effectively. It ensures that the tissues around the metal will not be distorted. The method is also computational efficient and effective for the CT images which contains several metal objects.
出处
《中国医疗器械杂志》
CAS
2009年第2期87-90,共4页
Chinese Journal of Medical Instrumentation
关键词
金属伪影
滤波反投影
混合法
metal artifacts, filtered back projection, hybrid algorithm
