A method of incorporating organ motion uncertainties into three-dimensional conformal treatment plans
A method of incorporating organ motion uncertainties into three-dimensional conformal treatment plans
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DOI：
10.1016/0360-3016(96)00008-9
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发表时间：
1996-05-01
影响因子：
7
通讯作者：
Fuks, Z
中科院分区：
文献类型：
--
作者：
Mageras, GS;Kutcher, GJ;Fuks, Z
目的：我们描述了一种将器官运动纳入三维（3D）适形治疗计划的方法，该方法预测器官运动对临床靶体积（CTV）和非靶器官的计算剂量的影响。该方法基于通过来自一组“参考”患者的多次计算机断层扫描（CT）对器官运动的测量，其中数据由目标和非目标器官的先前绘制的轮廓组成。计算机程序记录在参考数据中的扫描之间出现的轮廓位置和形状的差异，并且根据这些差异调整当前正在计划的“研究”患者的轮廓和剂量计算点，从而模拟器官运动，累积剂量-体积直方图（DVH），并且在参考患者扫描的集合上重复该过程，从而产生根据基于剂量的终点排序的治疗计划的集合。选择对应于终点中的指定置信下限和置信上限的两个计划，并且显示来自这些计划的DVH，以便与来自没有运动的标称计划的DVH进行比较。结果：作为该方法使用的一个例子，它被应用于前列腺癌的6场适形治疗计划，CTV和直肠壁的置信限DVH（其中计划分别按肿瘤控制和正常组织并发症的概率排序），并与标称计划进行比较。该方法提供了一种在存在器官运动时估计由治疗计划递送的剂量的不确定性的手段。该方法通常适用于多个CT扫描形式的数据可用的任何治疗部位，并且可以扩展到包括其他治疗不确定性，例如患者定位的变化。
Purpose: We describe a method of incorporating organ motion into three-dimensional (3D) conformal treatment plans, which predicts the effect of organ motion on the calculated dose to both the clinical target volume (CTV) and nontarget organs.Methods and Materials: The method is based on measurements of organ motion by means of multiple computed tomography (CT) scans from a group of ''reference'' patients, in which the data consist of previously drawn contours of the target and nontarget organs, A computer program records the differences in contour position and shape that occur between scans in the reference data, and according to those differences adjusts the contours and dose calculation points of a ''study'' patient currently being planned, thus simulating organ motion, Dose-volume histograms (DVHs) are accumulated, and the process is repeated over the set of reference patient scans, resulting in a set of treatment plans that are ranked according to a dose-based endpoint, Two plans are selected corresponding to specified lower and upper confidence limits in the endpoint, and the DVHs from these plans are displayed for comparison with the DVHs from the nominal plan in the absence of motion.Results: As an example of the method's use, it is applied to a 6-field conformal treatment plan for prostate cancer, Confidence limit DVHs of the CTV and rectal wall (in which the plans were ranked by probabilities for tumor control and normal tissue complication, respectively) are presented and compared to those from the nominal plan.Conclusion: The method provides a means of estimating the uncertainty in dose delivered by a treatment plan when organ motion is present, It is generally applicable to any treatment site for which data in the form of multiple CT scans are available, and can be extended to include other treatment uncertainties such as variation in patient positioning.