使用MCNPX和斑块模拟器软件对125个眼睛斑块的剂量分配的演变
Hosein Poorbaygi1, Elham Sardari2, Seyed Mahmoud Reza Aghamiri2
1Radiation Application Research School Nuclear Science and Technology Tehran Iran.
Precision radiation oncology
|May 8, 2025
概括
蒙特卡罗N-粒子扩展 (MCNPX) 和斑块模拟器 (PS) 软件被用于评估眼睛斑块辐射治疗眼睛黑色素瘤. MCNPX显示剂量分布低于PS,表明准确度的潜在差异.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 眼科医生 眼科 眼科
背景情况:
- 眼斑辐射疗法,特别是使用-125 (125I) 种子,是胆膜黑色素瘤的首要治疗方法.
- 精确的剂量测量对于有效治疗和最小化副作用至关重要.
- 将不同的治疗计划软件进行比较对于了解剂量分配变化至关重要.
研究的目的:
- 通过使用蒙特卡罗N粒子扩展 (MCNPX) 和斑块模拟器 (PS) 软件,研究和比较围绕125眼斑块的剂量分布.
- 评估用于眼睛黑色素瘤治疗计划的剂量计计算的准确性.
主要方法:
- 使用MCNPX代码进行剂量测量评估和对I COMS斑块的异剂量曲线进行比较.
- 使用PS治疗规划软件计算异位剂曲线和剂量分布,用于125I COMS斑块.
- 根据现有文献验证了结果,并指出COMS斑块的最大相对差异为9%-10%.
主要成果:
- 根据MCNPX计算,剂量分布大约比PS.计算的剂量分布低27.7%-35.4%.
- 差异可能源于125I源光谱,种子设计和PS.I使用的剂量算法之间的差异.
- 在贴片插入表面附近提供准确的剂量分配细节方面,PS表现出局限性.
结论:
- 对于125个眼睛斑块,MCNPX和PS之间的剂量分配计算存在显著差异.
- PS可能无法准确地表示靠近斑块表面的剂量分布.
- 建议对MCNPX和PS中使用的源参数和算法进行进一步调查,以解决差异.
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