由正电压X射线诱导的闪光效应
Devin Miles1, Daniel Sforza1, John W Wong1
1Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.
概括
使用千伏X射线的超高剂量率 (FLASH) 辐射可以在不影响瘤控制的情况下节省小鼠的正常组织. 这项研究证明了用于临床前FLASH辐射研究的可访问方法.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 临床前研究 临床前研究
背景情况:
- 超高剂量率 (FLASH) 辐射疗法表明,它有望在保持瘤控制的同时保护正常组织.
- 千伏 (kV) 的X射线源广泛可用,但尚未对FLASH应用进行广泛研究.
研究的目的:
- 为临床前FLASH辐射研究实施和评估旋转阳极千伏X射线源.
- 研究FLASH辐射对小鼠正常组织和瘤反应的体内影响.
主要方法:
- 使用旋转阳极X射线管和80千瓦发电机,将FLASH (87Gy/s) 和常规 (CONV;<0.05Gy/s) 辐射剂量传递给小鼠后肢.
- 皮肤损伤和瘤生长抑制的组织学评估 (B16F10模型) 在辐射后8周被评估.
- 在幻影和体内的活体剂量测量使用Gafchromic膜和热发光剂量测量仪进行.
主要成果:
- 与8周的CONV照射相比,FLASH照射导致正常组织损伤 (炎症,,增生,纤维化) 显著减少.
- 在35 Gy的FLASH和CONV辐射之间没有观察到瘤生长抑制的显著差异.
- 正常组织的节省效果是剂量依赖的,特别是43 Gy的.
结论:
- 旋转阳极kVX射线源可以达到适合小动物研究的临床前FLASH剂量率.
- 闪光辐射节省了正常组织的毒性,而不牺牲瘤生长抑制.
- 这项研究为实验室研究FLASH效应提供了一个新的,易于使用的方法.
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