应用Raystation治疗计划系统脚本实现Hausdorff距离的计算

Calculating the Hausdorff distance based on the scripting in RayStation treatment planning system

目的应用RayStation治疗计划系统脚本实现Hausdorff距离的计算，并用于CT和MR图像自动配准中脑干形变误差的衡量。方法在RayStation 4.7治疗计划系统中，应用IronPython语言编写脚本，先读取2个感兴趣区域的轮廓点集，然后计算它们之间的Hausdorff距离。结合XAML语言设计图形用户界面，实现Hausdorff距离的可视化输出。运行脚本后，在RayStation中弹出图形用户界面，从中选择需要计算距离的2个感兴趣区，然后单击＂计算＂按钮可获得相应的距离以及算法的执行时间。结果从20例头颈部肿瘤患者的图像资料中，计算得到脑干的平均Hausdorff距离为1.20 cm，平均程序执行时间为11.01 s。结论应用RayStation治疗计划系统脚本可实现2个感兴趣区的Hausdorff距离计算，可满足临床及科研工作中需要计算Hausdorff距离的需求。

Objective To calculate out the Hausdorff distance based on the scripting in RayStation treatment planning system, which was then applied in measuring the deformation error of brain stem during image automatic registration between CT and MR.Methods Scripting was edited in RayStation system （version 4.7） by using IronPython. The set of point coordinates on the contour of any two region of interest （ROI） had been found firstly, then the Hausdorff distance between the two point sets was calculated out. A graphical user interface （GUI） was designed by using XAML to acquire the visualized output of Hausdorff distance. GUI appeared when the script was run, where two ROIs was selected, then the corresponding Hausdorff distance and the running time were displayed by pressing the ＂Calculate＂ button. Results The mean Hausdorff distance of brain stem in 20 patients with head and neck neoplasms was 1.20 cm while the mean elapsed time was 11.01s.Conclusions Hausdorff distance of any two ROIs can be calculated out by using the developed method. GUI is designed to realize the visual interaction with RayStation system. Therefore, the RayStation system satisfies the demands of Hausdorff distance calculation in both clinical and research work.