光学学报, 2016, 36 (9): 0911008, 网络出版: 2016-09-09
锥束CT圆加直线轨迹反投影滤波重建算法
Backprojection Filtering Reconstruction Algorithm for Circle-Plus-Line Trajectory in Cone Beam CT
成像系统 M-line重建 差分反投影 圆加直线轨迹 锥束CT imaging systems M-line reconstruction difference backprojection circle-plus-line trajectory cone beam computed tomography
摘要
针对圆加直线轨迹重建,提出了一种基于M-line的反投影滤波重建算法。结合圆加直线轨迹几何特点,给出简洁合适的M-lines选取方法;通过求解穿过M-line上重建点的R-line的端点坐标,确定反投影积分区间,从而推导得到算法的具体重建公式。证明圆加直线轨迹重建区域(圆轨迹平面区域除外)R-line的唯一性,并求解扫描所需最短的直线轨迹长度。实验结果表明,该算法能够在大锥角扫描时获得较好的重建结果,明显提高了重建图像质量。
Abstract
The backprojection filtering reconstruction algorithm is proposed based on M-line for the circle-plus-line trajectory. The concise and appropriate M-line selection method is proposed, combined with the geometrical characteristics of the trajectory. The backprojection integral interval is obtained through solving the R-line coordinates which pass through the reconstructed point on the M-line, and the proposed reconstruction formula is derived. It is proved that the R-line within the reconstruction region for the circle-plus-line trajectory is unique, and the shortest length of the needed line trajectory is solved. Experimental results show that the proposed method can improve reconstruction image quality in large cone-angle scanning.
李增光, 李磊, 韩玉, 席晓琦, 闫镔, 李建新. 锥束CT圆加直线轨迹反投影滤波重建算法[J]. 光学学报, 2016, 36(9): 0911008. Li Zengguang, Li Lei, Han Yu, Xi Xiaoqi, Yan Bin, Li Jianxin. Backprojection Filtering Reconstruction Algorithm for Circle-Plus-Line Trajectory in Cone Beam CT[J]. Acta Optica Sinica, 2016, 36(9): 0911008.