Yan Guorui, Tian Jie, Zhu Shouping, Qin Chenghu, Dai Yakang, Yang Fei, Dong Di, Wu Ping
Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China.
IEEE Trans Inf Technol Biomed. 2010 Jul;14(4):1053-61. doi: 10.1109/TITB.2009.2036368. Epub 2009 Dec 11.
Katsevich reconstruction algorithm represents a breakthrough for helical cone-beam computed tomography (CT) reconstruction, because it is the first exact cone-beam reconstruction algorithm of filtered backprojection (FBP) type with 1-D shift-invariant filtering. Although FBP-type reconstruction algorithm is effective, 3-D CT reconstruction is time-consuming, and the accelerations of Katsevich algorithm on CPU or cluster have been widely studied. In this paper, Katsevich algorithm is accelerated by using graphics processing unit, including flat-detector and curved-detector geometry in the case of helical orbit. An overscan formula is derived, which helps to avoid unnecessary overscan in practical CT scanning. Based on the overscan formula, a volume-blocking method in device memory is proposed. One advantage of the blocking method is that it can reconstruct large volume with high speed.
卡采维奇重建算法是螺旋锥束计算机断层扫描（CT）重建领域的一项突破，因为它是首个具有一维平移不变滤波的精确锥束滤波反投影（FBP）型重建算法。尽管FBP型重建算法很有效，但三维CT重建耗时较长，并且卡采维奇算法在CPU或集群上的加速方法已得到广泛研究。本文利用图形处理单元对卡采维奇算法进行加速，包括螺旋轨道情况下的平板探测器和曲面探测器几何结构。推导了一种过扫描公式，有助于在实际CT扫描中避免不必要的过扫描。基于该过扫描公式，提出了一种设备内存中的体块划分方法。该块划分方法的一个优点是能够高速重建大体积数据。
