Evaluation of deformable image registration for contour propagation between CT and cone-beam CT images in adaptive head and neck radiotherapy
Evaluation of deformable image registration for contour propagation between CT and cone-beam CT images in adaptive head and neck radiotherapy
复制标题
自适应头颈放疗中CT与锥束CT图像之间轮廓传播的变形图像配准评估
DOI：
10.3233/thc-161204
复制
发表时间：
2016-01-01
影响因子：
1.6
通讯作者：
Zhen, X.
中科院分区：
文献类型：
--
作者：
Li, X.;Zhang, Y. Y.;Zhen, X.
可变形图像配准（Deformable Image Registration，简称RDR）是自适应放射治疗（Adaptive Radiotherapy，ART）中的一项关键技术，用于在计划计算机断层扫描（Computerized Tomography，简称CT）图像和治疗CT/锥形束CT（Cone-beam CT，简称CBCT）图像之间传播轮廓，以考虑器官变形，从而进行治疗再计划。为了验证风险器官（OAR）轮廓映射的能力和准确性，七个基于强度的风险器官算法策略在计划CT和每周CBCT图像上进行了测试，这些图像来自6名头颈部癌症患者，他们接受了6周至7周的调强放射治疗（IMRT）。三个相似性度量，i。e.采用Dice相似系数（DSC）、百分比误差（PE）和Hausdorff距离（HD）来测量传播的轮廓与医生描绘的地面真实值之间的一致性。结果发现，所有评估的并行算法的性能下降，作为治疗的进行。除了在DSC和PE方面产生最差结果的双力恶魔（DFD）之外，在不同的双力恶魔算法之间没有观察到统计学上显著的性能差异（p > 0.05）。对于度量HD，所有的HDM算法的表现都不令人满意，没有统计学显著的性能差异（p = 0.273）。这些结果表明，在利用本研究中涉及的基于强度的增强算法使CT和CBCT之间的OAR轮廓变形时，应特别小心，尤其是对于那些对比度较低的器官。
Deformable image registration (DIR) is a critical technic in adaptive radiotherapy (ART) to propagate contours between planning computerized tomography (CT) images and treatment CT/Cone-beam CT (CBCT) image to account for organ deformation for treatment re-planning. To validate the ability and accuracy of DIR algorithms in organ at risk (OAR) contours mapping, seven intensity-based DIR strategies are tested on the planning CT and weekly CBCT images from six Head & Neck cancer patients who underwent a 6 similar to 7 weeks intensity-modulated radiation therapy (IMRT). Three similarity metrics, i. e. the Dice similarity coefficient (DSC), the percentage error (PE) and the Hausdorff distance (HD), are employed to measure the agreement between the propagated contours and the physician delineated ground truths. It is found that the performance of all the evaluated DIR algorithms declines as the treatment proceeds. No statistically significant performance difference is observed between different DIR algorithms (p > 0.05), except for the double force demons (DFD) which yields the worst result in terms of DSC and PE. For the metric HD, all the DIR algorithms behaved unsatisfactorily with no statistically significant performance difference (p = 0.273). These findings suggested that special care should be taken when utilizing the intensity-based DIR algorithms involved in this study to deform OAR contours between CT and CBCT, especially for those organs with low contrast.