Zhang Geoffrey, Huang Tzung-Chi, Guerrero Thomas, Lin Kang-Ping, Stevens Craig, Starkschall George, Forster Ken
Department of Radiation Oncology, H. Lee Moffitt Cancer Center, University of South Florida, Tampa, Florida.
Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas.
J Appl Clin Med Phys. 2008 Feb 5;9(1):59-69. doi: 10.1120/jacmp.v9i1.2738.
A 3-dimensional (3D) optical flow program that includes a multi-resolution feature has been developed and applied to 3D anatomical structure and gross tumor volume (GTV) contour mapping for 4-dimensional (4D) CT data. The study includes contour mapping for 3 real patient CT data sets, and also for a thoracic phantom in which the displacement for each voxel is known. Of the real patient CT data sets, one set has been used to map contours of lung and GTV over all the respiration phases, while the others were studied using only the end inspiration and end expiration phases, in which the displacement between the phases were the largest. Including the residual motion in the 4D CT data and motion table shaking, the optical flow calculation agrees to within 1 mm with the known displacement. Excluding those errors that are not introduced by optical flow algorithm, the agreement can be within 0.1 mm with a displacement magnitude of 24 mm. The mapped contours of lungs, liver, esophagus, GTV, etc. in real patient 4D CT images were acceptable to clinicians. The 3D optical flow program is a good tool for anatomical structure and tumor volume contour mapping across 4D CT scans.
一种包含多分辨率特征的三维（3D）光流程序已被开发出来，并应用于四维（4D）CT数据的三维解剖结构和大体肿瘤体积（GTV）轮廓映射。该研究包括对3个真实患者CT数据集以及一个已知每个体素位移的胸部体模进行轮廓映射。在真实患者CT数据集中，一组用于映射所有呼吸阶段的肺部和GTV轮廓，而其他数据集仅使用吸气末和呼气末阶段进行研究，这两个阶段之间的位移最大。包括4D CT数据中的残余运动和运动台抖动，光流计算与已知位移的误差在1毫米以内。排除那些不是由光流算法引入的误差，对于24毫米的位移幅度，误差可在0.1毫米以内。真实患者4D CT图像中映射的肺部、肝脏、食管、GTV等轮廓，临床医生认为是可接受的。3D光流程序是跨4D CT扫描进行解剖结构和肿瘤体积轮廓映射的良好工具。
