Mutual information based CT registration of the lung at exhale and inhale breathing states using thin-plate splines
Mutual information based CT registration of the lung at exhale and inhale breathing states using thin-plate splines
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DOI：
10.1118/1.1803671
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发表时间：
2004-11-01
期刊：
影响因子：
3.8
通讯作者：
Kessler, ML
中科院分区：
文献类型：
--
作者：
Coselmon, MM;Balter, JM;Kessler, ML
动态放射治疗建模和治疗技术的出现需要一个基础设施来衡量各种干预措施(屏气、门控、跟踪)的优点。创建考虑运动和变形的治疗计划模型可以评估这些技术的相对价值。为了开发运动和变形器官(如肺)的治疗规划模型，需要考虑变形的登记工具。我们测试了一种基于互信息的图像配准工具的精度，该工具使用薄板样条线来驱动控制点的选择，并根据单纯形算法迭代对齐。11名患者分别在屏气、正常吸气和呼气状态下进行了顺序CT扫描。将呼气性右肺从CT上分割出来作为参考模型。对于每个患者，使用30个控制点将吸气CT右肺与呼气CT右肺对齐。对齐精度(实际吸气位置和预测吸气位置之差的标准差)由血管和支气管分叉的位置确定，并发现沿RL、AP和IS方向的对准精度分别为1.7、3.1和3.6 mm。对齐精确度与仅在AP和IS方向呼吸时测量的运动量有显着差异。包括薄板样条线在内的比对精度比使用仿射变换和相同的迭代和评分方法更准确。这项技术显示了用于四维(4-D)治疗计划的肺动态模型的未来发展前景。(C)2004年美国医学物理学家协会。
The advent of dynamic radiotherapy modeling and treatment techniques requires an infrastructure to weigh the merits of various interventions (breath holding, gating, tracking). The creation of treatment planning models that account for motion and deformation can allow the relative worth of such techniques to be evaluated. In order to develop a treatment planning model of a moving and deforming organ such as the lung, registration tools that account for deformation are required. We tested the accuracy of a mutual information based image registration tool using thin-plate splines driven by the selection of control points and iterative alignment according to a simplex algorithm. Eleven patients each had sequential CT scans at breath-held normal inhale and exhale states. The exhale right lung was segmented from CT and served as the reference model. For each patient, thirty control points were used to align the inhale CT right lung to the exhale CT right lung. Alignment accuracy (the standard deviation of the difference in the actual and predicted inhale position) was determined from locations of vascular and bronchial bifurcations, and found to be 1.7, 3.1, and 3.6 mm about the RL, AP, and IS directions. The alignment accuracy was significantly different from the amount of measured movement during breathing only in the AP and IS directions. The accuracy of alignment including thin-plate splines was more accurate than using affine transformations and the same iteration and scoring methodology. This technique shows promise for the future development of dynamic models of the lung for use in four-dimensional (4-D) treatment planning. (C) 2004 American Association of Physicists in Medicine.