【摘要】 提出了基于直接螺旋半扫描数据的有序子集期望最大化(OSEM)迭代重建.该方案省略了螺旋CT中对投影数据的插值步骤,利用螺旋CT中相邻重建层间的相似性,将当前层的重建结果作为下一层重建时OSEM算法的初始输入.实验结果表明,在螺距较小的情况下,该重建方案使得螺旋CT在重建质量优于滤波反投影的前提下,所需的重建时间显著减少.更多还原

【Abstract】 This paper proposed a modified ordered subsets expectation maximization(OSEM) reconstruction based on the direct helical half-scan data.This scheme omits the interpolation for projection data,and utilizes the similarity between two adjacent slices,that is,takes the current reconstruction image as the initial input of OSEM to reconstruct the next slice,the rest can be deduced by analogy.The experimental results show that when the pitch of helical CT is small,this proposed scheme can greatly reduce the reconstruction time with better image quality than filterd back-projection(FBP).更多还原