空气流入真空型固定装置的影响 设置错误
Fumiyasu Matsubayashi1, Tatsuya Kamima2, Yasushi Ito2
1Radiation Oncology Department, Cancer Institute Hospital, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-Ku, Tokyo, 135-8550, Japan. fumiyasu.matsubayashi@jfcr.or.jp.
Radiological physics and technology
|June 18, 2024
概括
真空型固定装置 (VID) 的每周通气显著减少了头癌放射治疗中的设置错误. 这通过在VIDS中保持一致的压力来提高患者设置可重现性.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 生物医学工程 生物医学工程
背景情况:
- 真空型固定装置 (VID) 在放射治疗中对患者的定位至关重要.
- 在VID中保持一致的压力对于准确的患者设置至关重要.
- 空气流入可能导致压力波动,可能会增加设置错误.
研究的目的:
- 为了研究空气流入VIDS对放射治疗期间设置错误的影响.
- 为了比较每周通胀VIDS的患者和非通胀VIDS的患者之间的设置错误.
- 评估VID压力变化与设置精度之间的关系.
主要方法:
- 70名头癌患者被分为两组:每周VIDS通气 (V组) 和没有通气 (N组).
- 系统错误 (Σ) 和随机错误 (σ) 为每个患者计算.
- 在组之间比较了设置错误的整体平均值 (μ) 和标准偏差 (SD整体).
- 监测了 VID 内的暂时压力变化.
主要成果:
- 虽然整体平均值 (μ) 类似 (在0.20mm和0.2°范围内),但SD整体在各组之间有显著差异.
- 与N组 (0.87°) 相比,V组在滚轴上显示较低的SD整体 (0.58°).
- 系统 (Σ) 和随机 (σ) 错误在V组的所有轴上始终较低.
- 每周通缩维持了VIDs压力在-20kPa左右,而非通缩的VIDs压力增加到-5kPa.
结论:
- 在VIDS中通过每周通气的有效压力控制可以减少患者之间的差异.
- 定期的VIDs通气增强了个体患者的设置可重复性.
- 这导致整体设置错误的变化较小,提高了治疗的准确性.
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