A method for incorporating organ motion due to breathing into 3D dose calculations
A method for incorporating organ motion due to breathing into 3D dose calculations
复制标题
DOI：
10.1118/1.598577
复制
发表时间：
1999-05-01
期刊：
影响因子：
3.8
通讯作者：
Ten Haken, RK
中科院分区：
文献类型：
--
作者：
Lujan, AE;Larsen, EW;Ten Haken, RK
提出了一种结合呼吸引起的治疗内器官运动对肝病治疗剂量计算的影响的方法。我们的方法是基于静态剂量分布与描述运动性质的概率分布函数(PDF)的卷积。这里假设呼吸引起的器官运动是一维的(上下方向)，并使用周期性但不对称的函数(呼气比吸气花费更多的时间)来建模。根据我们机构使用的肝脏剂量递增方案，使用卷积方法计算的剂量分布与使用剂量差显示的静态剂量分布和非受累肝脏的有效体积(V-Jeff)进行比较。基于卷积的计算也与对治疗的各个部分进行建模的直接模拟进行比较。分析表明，结合器官运动可能会导致根据未受累肝脏的V-Eff而开出的治疗剂量发生变化。基于卷积的计算和各种最坏情况的直接模拟的比较表明，单一的基于卷积的计算足以预测给定的示例性治疗计划的剂量分布。(C)1999年美国物理学家医学协会。[S0094-2405(99)00405-8]。
A method is proposed that incorporates the effects of intratreatment organ motion due to breathing on the dose calculations for the treatment of liver disease. Our method is based on the convolution of a static dose distribution with a probability distribution function (PDF) which describes the nature of the motion. The organ motion due to breathing is assumed here to be one-dimensional (in the superior-inferior direction), and is modeled using a periodic but asymmetric function (more time spent at exhale versus inhale). The dose distribution calculated using convolution-based methods is compared to the static dose distribution using dose difference displays and the effective volume (V-eff) of the uninvolved liver, as per a liver dose escalation protocol in use at our institution. The convolution-based calculation is also compared to direct simulations that model individual fractions of a treatment. Analysis shows that incorporation of the organ motion could lead to changes in the dose prescribed for a treatment based on the V-eff of the uninvolved liver. Comparison of convolution-based calculations and direct simulation of various worst-case scenarios indicates that a single convolution-based calculation is sufficient to predict the dose distribution for the example treatment plan given. (C) 1999 American Association of Physicists in Medicine. [S0094-2405(99)00405-8].