基于FDK反投影权重的锥束DSA重建算法  

DSA cone beam reconstruction algorithm based on backprojection weight FDK

作　　者：杨宏成[1,2] 高欣[3] 张涛[1,3] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所,吉林长春130000 [2]中国科学院大学,北京100049 [3]中国科学院苏州生物医学工程技术研究所,江苏苏州215163

出　　处：《江苏大学学报（自然科学版）》2013年第2期190-195,共6页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(81000651);江苏省自然科学基金资助项目(BK2010236);苏州市技术专项项目(ZXS201003);中科院知识创新工程重要方向项目(KGCX-YW-909-1)

摘　　要：针对锥束数字减影血管造影成像系统(DSA)锥角增大而导致锥束伪影严重的问题,提出了一种基于FDK的反投影权重锥束DSA重建算法.分析了圆扫描轨迹远端伪影的成因,针对短扫描阴影区域导致的Radon空间数据缺失,提出了一种距离变量的反投影权重函数,并将其作为约束条件引入到FDK算法中,实现扫描轨迹远端区域的数据补偿,扩大图像重建区域.应用该算法对无噪声和有噪声的模拟投影数据,及自行研发的锥束DSA的实际扫描数据分别进行了重建试验.结果表明,文中算法较FDK类算法(Parker-FDK)对大锥角投影数据可明显抑制锥角伪影,其归一化均方距离判据和归一化平均绝对距离判据比Parker-FDK均降低了5%.To solve the problem of cone beam artifacts resulting from the large cone angle in cone beam digital subtraction angiography of DSA, a novel backprojection weight reconstruction algorithm based on the frame work of FDK（BPW-FDK） was proposed. The cause of the cone beam artifacts away from the rotating track was analyzed. To solve the data deficiency in Randon space, a new backprojection weight function based on distance was designed and incorporated into the original FDK algorithm as a constraint condition for data compensation in the region far away from the rotating track to expand the reconstruction region. The reconstructing experiments were conducted on the images from simulated projections with noise or without noise and the real projections from a self-development DSA scanner. The results show that the proposed algorithm has obvious superiority over the Parker-FDK algorithm in suppression of cone beam artifacts for large cone angle projections. Compared with the Parker-FDK, the normalized mean square distance criterion and the normalized mean absolute distance criterion of the proposed algorithm are decreased by 5%.

关 键 词：锥束重建 FDK算法 短扫描 反投影权重 DSA 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构]