在参考和相对剂量测量,剂量计算和患者设置中的不确定性量化,在现代外部光束放射治疗中
Naoki Kinoshita1, Morihito Shimizu2, Kana Motegi3
1Department of Radiology, Faculty of Medical Sciences, University of Fukui, 23-3, Matsuoka-Shimoaituki, Eiheiji, Yoshida, Fukui, 910-1193, Japan. nkino@u-fukui.ac.jp.
Radiological physics and technology
|November 14, 2024
概括
减少外部光束放射治疗 (EBRT) 的不确定性对于患者的治疗结果至关重要. 本研究确定了EBRT不确定性的关键因素,强调相对剂量计和剂量计算是需要改进的领域.
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:
- 外部光束放射疗法 (EBRT) 的不确定性对患者治疗结果产生重大影响.
- 识别EBRT不确定性的主要贡献者对于提高剂量递送精度至关重要.
- 很少有研究全面调查了导致EBRT不确定性的因素.
研究的目的:
- 调查有助于减少在将辐射剂量传递到目标体积的不确定性的因素.
- 评估脑内疾病EBRT过程的关键步骤中的不确定性.
主要方法:
- 将EBRT过程分为四个步骤:参考剂量计,相对剂量计 (PDD,OCR),剂量计算和患者设置.
- 使用测量不确定性表达指南和未经校正的偏移方法评估不确定性.
- 利用来自临床线性加速器的4,6和10MV平面化光子束用于常规分成的内EBRT.
主要成果:
- 确定的主要不确定性贡献者:光束质量因素 (参考剂量计);电荷测量,电池深度,SSD,水蒸发,场面大小 (相对剂量计);剂量计算精度 (剂量计算);图像注册,同心巧合,旋转变化,断片内运动 (患者设置).
- 相对剂量测量和剂量计算步骤,特别是半阴偏离中心比率,不确定性超过5% (覆盖率为1).
- 这些两个步骤被确定为评估EBRT过程中的主要不确定性来源.
结论:
- 相对剂量测量和剂量计算步骤是关键领域,需要在EBRT中显著降低不确定性.
- 解决这些步骤中的不确定性对于提高放射治疗的精度和疗效至关重要.
- 需要进一步的研究和技术进步,以尽量减少EBRT交付中的不确定性.
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