在点扫描质子疗法中使用马电子顶点成像的范围转移验证
Sung Hun Kim1, Jong Hwi Jeong1, Youngmo Ku2
1Center for Proton Therapy, National Cancer Center, Gyeonggi-do, Republic of Korea.
Medical physics
|September 18, 2023
概括
质子治疗中的范围不确定性是一个关键的安全问题. 玛电子顶点成像 (GEVI) 系统有效地测量了高精度和精度的质子束范围偏移至1毫米,提高了患者的安全性.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 核仪器仪表 核仪器仪表 核仪器仪表
背景情况:
- 质子疗法利用布拉格峰值来确定剂量一致性,但光束范围的不确定性显著影响治疗质量和患者安全.
- 管理范围的不确定性对于有效的质子疗法至关重要.
- 快速马成像 (PGI) 是质子治疗中范围验证的一个有前途的技术.
研究的目的:
- 报告升级的马电子顶点成像 (GEVI) 系统在笔光束扫描 (PBS) 质子疗法中的快速马成像 (PGI) 的第一个实验结果.
- 评估GEVI系统在测量质子束范围转移方面的能力.
- 评估GEVI系统在体内范围验证的准确性和精度.
主要方法:
- 使用了同质的板块和人类形象的幽灵,具有定义的规划目标体积 (PTV).
- 引入了各种范围转移场景和同步的快速马 (PG) 测量与光束照射.
- 通过分析聚合PG分布中的心点变化,使用范围转移映射,置信区间估计和统计假设测试来估计范围的变化.
主要成果:
- 范围转移映射显示了与真实转移值保持一致的明显趋势,尽管在低统计点的微小波动.
- GEVI系统的整体准确度和精度分别为0.36mm和0.20mm.
- 统计测试证实了该系统能够检测小到1毫米的移动,并区分不同的移动大小.
结论:
- 在点扫描质子疗法中,GEVI系统可用于测量范围的变化.
- 实验结果验证了该系统的高准确性和精度,可检测高达1毫米的范围变化.
- 作为一种PGI系统,GEVI系统在质子疗法中的体内范围验证方面显示出显著的希望.
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