用AAPM医学物理实践指南5.b进行体积调制弧度疗法治疗计划系统的剂量计验证
Sriram Prasath1,2, Padmanabhan Ramesh Babu2
1Division of Medical Physics, Department of Radiation Oncology, Tata Medical Center, Newtown, Rajarhat, Kolkata, West Bengal, India.
Asian Pacific journal of cancer prevention : APJCP
|May 29, 2024
概括
这项研究验证了使用兆电压 (MV) 光子束进行体积调制弧线疗法 (VMAT) 的剂量计算精度. 分析异构算法 (AAA) 和AUROS XB (AXB) 算法都表现出了对平面化波器 (FF) 和平面化无波器 (FFF) 束的高精度.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 放射治疗剂量计 放射治疗剂量计
背景情况:
- 精确的剂量计算对于有效的放射治疗至关重要.
- 卷度调制弧线疗法 (VMAT) 需要精确的剂量计算,以提供最佳的治疗.
- 治疗计划系统 (TPS) 算法的验证对于确保患者安全和治疗疗效至关重要.
研究的目的:
- 评估使用兆电压 (MV) 光子束进行体积调节弧疗法 (VMAT) 的剂量计算的精度.
- 为了验证AUROS XB (AXB) 和分析无otropic算法 (AAA) 剂量计算算法的准确性.
- 确保符合AAPM医学物理实践指南 (MPPG 5b) 的VMAT验证.
主要方法:
- 在VMAT验证测试中,使用6 MV平面化波器 (FF) 和无平面化波器 (FFF) 束进行了验证.
- 用Eclipse V.15.1治疗计划系统 (TPS) 中的AAA和AXB算法进行了剂量计算.
- 测量包括点剂量 (PD),体内剂量测量 (热发光剂量计 - TLD) 和使用Rando Phantom的端到端 (E2E) 测试.
主要成果:
- 百分比深度剂量 (PDD) 和输出因子的TPS计算和测量值之间的平均差异分别在1%和0.5%之间.
- 对于TG 119和TG 244测试集,AAA和AXB算法的点剂量 (PD) 的平均差异分别小于0.9%和0.8%.
- 在Rando Phantom的端到端测试显示,对于6个MV FF和FFF光束,平均剂量差异在0.08%以内.
结论:
- 已经成功验证了Eclipse TPS及其AAA和AXB算法用于VMAT剂量计算的准确性.
- 该研究证实了AAPM的TG 119和TG 244测试在验证剂量计算和复杂的临床情景方面的有用性.
- 端到端测试对于验证整个放射治疗工作流程至关重要,从成像到治疗.
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