Niu Xiaofeng, Yang Yongyi, Jin Mingwu, Wernick Miles N, King Michael A
Department of Electrical and Computer Engineering, Illinois Institute of Technology, Chicago, IL 60616 USA.
IEEE Trans Nucl Sci. 2010;57(6):1085-1095. doi: 10.1109/TNS.2010.2047731.
In our recent work, we proposed an image reconstruction procedure aimed to unify gated imaging and dynamic imaging in nuclear cardiac imaging. With this procedure the goal is to obtain an image sequence from a single acquisition which shows simultaneously both cardiac motion and tracer distribution change over the course of imaging. In this work, we further develop and demonstrate this procedure for fully 5D (3D space plus time plus gate) reconstruction in gated, dynamic cardiac SPECT imaging, where the challenge is even greater without the use of multiple fast camera rotations. For 5D reconstruction, we develop and compare two iterative algorithms: one is based on the modified block sequential regularized EM (BSREM-II) algorithm, and the other is based on the one-step late (OSL) algorithm. In our experiments, we simulated gated cardiac imaging with the NURBS-based cardiac-torso (NCAT) phantom and Tc99m-Teboroxime as the imaging agent, where acquisition with the equivalent of only three full camera rotations was used during the course of a 12-minute postinjection period. We conducted a thorough evaluation of the reconstruction results using a number of quantitative measures. Our results demonstrate that the 5D reconstruction procedure can yield gated dynamic images which show quantitative information for both perfusion defect detection and cardiac motion.
在我们最近的工作中，我们提出了一种图像重建程序，旨在将核心脏成像中的门控成像和动态成像统一起来。通过这个程序，目标是从单次采集中获得一个图像序列，该序列能同时显示成像过程中心脏运动和示踪剂分布的变化。在这项工作中，我们进一步开发并展示了这种用于门控动态心脏单光子发射计算机断层显像（SPECT）成像中全5D（三维空间加时间加门控）重建的程序，在不使用多个快速相机旋转的情况下，这里的挑战更大。对于5D重建，我们开发并比较了两种迭代算法：一种基于改进的块序贯正则化期望最大化（BSREM-II）算法，另一种基于一步滞后（OSL）算法。在我们的实验中，我们使用基于非均匀有理B样条（NURBS）的心脏躯干（NCAT）模型和锝99m - 替博肟作为成像剂模拟门控心脏成像，在注射后12分钟的过程中仅使用相当于三个完整相机旋转的采集。我们使用多种定量方法对重建结果进行了全面评估。我们的结果表明，5D重建程序可以生成门控动态图像，这些图像能显示用于灌注缺损检测和心脏运动的定量信息。
