Abstract：
Objective.The purpose of this study is to develop a treatment planning process (TPP) for non-isocentric dynamic trajectory radiotherapy (DTRT) using dynamic gantry rotation, collimator rotation, table rotation, longitudinal, vertical and lateral table translations and intensity modulation and to validate the dosimetric accuracy.Approach.The TPP consists of two steps. First, a path describing the dynamic gantry rotation, collimator rotation and dynamic table rotation and translations is determined. Second, an optimization of the intensity modulation along the path is performed. We demonstrate the TPP for three use cases. First, a non-isocentric DTRT plan for a brain case is compared to an isocentric DTRT plan in terms of dosimetric plan quality and delivery time. Second, a non-isocentric DTRT plan for a craniospinal irradiation (CSI) case is compared to a multi-isocentric intensity modulated radiotherapy (IMRT) plan. Third, a non-isocentric DTRT plan for a bilateral breast case is compared to a multi-isocentric volumetric modulated arc therapy (VMAT) plan. The non-isocentric DTRT plans are delivered on a TrueBeam in developer mode and their dosimetric accuracy is validated using radiochromic films.Main results.The non-isocentric DTRT plan for the brain case is similar in dosimetric plan quality and delivery time to the isocentric DTRT plan but is expected to reduce the risk of collisions. The DTRT plan for the CSI case shows similar dosimetric plan quality while reducing the delivery time by 45% in comparison with the IMRT plan. The DTRT plan for the breast case showed better treatment plan quality in comparison with the VMAT plan. The gamma passing rates between the measured and calculated dose distributions are higher than 95% for all three plans.Significance.The versatile benefits of non-isocentric DTRT are demonstrated with three use cases, namely reduction of collision risk, reduced setup and delivery time and improved dosimetric plan quality.
摘要：
Objective.本研究的目的是开发使用动态机架旋转的非等中心动态轨迹放射治疗（DTRT）的治疗计划流程（TPP），准直器旋转,表旋转,纵向,垂直和横向表平移和强度调制，并验证剂量测定的准确性。方法。TPP包括两个步骤。首先,描述动态机架旋转的路径，确定准直器旋转和动态工作台旋转和平移。第二,执行沿路径的强度调制的优化。我们展示了三个用例的TPP。首先,在剂量测定计划质量和交付时间方面，将针对大脑病例的非等中心DTRT计划与等中心DTRT计划进行了比较。第二,将颅脊髓照射(CSI)病例的非等中心DTRT计划与多等中心调强放疗(IMRT)计划进行比较.第三，将双侧乳腺病例的非等中心DTRT计划与多等中心容积调节电弧治疗(VMAT)计划进行比较.非等中心DTRT计划以开发人员模式在TrueBeam上交付，并使用辐射变色胶片验证其剂量测定精度。主要结果。大脑病例的非等中心DTRT计划在剂量测定计划质量和交付时间上与等中心DTRT计划相似，但有望降低碰撞风险。与IMRT计划相比，CSI案例的DTRT计划显示出类似的剂量测定计划质量，同时将交付时间减少了45％。与VMAT计划相比，针对乳腺病例的DTRT计划显示出更好的治疗计划质量。对于所有三个计划，测得的剂量分布和计算的剂量分布之间的伽马通过率均高于95％。意义。非等中心DTRT的多功能优势在三个用例中得到了证明，即降低碰撞风险，减少设置和交付时间，提高剂量测定计划质量。
