We propose a novel understanding of two characteristics of the planning target volume (PTV) that affect the intermediate‐dose spill in lung stereotactic body radiation therapy (SBRT) as measured by R50%. This phantom model research investigates two characteristics of the PTV that have a marked effect on the value of R50%: the mean dose deposited within the PTV (D_av) and the surface area of the PTV (SA_PTV).

中文翻译：

---

肺SBRT中R50％与PTV表面积之间的生理上有意义的关系。

我们提出了对计划目标量（PTV）的两个特征的新颖理解，这些特征会影响R50％的肺立体定向放射治疗（SBRT）的中等剂量溢出。这项幻影模型研究调查了PTV的两个特征，这些特征对R50％的值具有显着影响：沉积在PTV内的平均剂量（D _av）和PTV的表面积（SA _PTV）。