外平面接触屏和mA调制 - 对胎儿吸收剂量的影响
Heli R S Larjava1, Chibuzor T M Eneh1, Aleksi Saikkonen2
1Department of Medical Physics and Department of Radiology, Turku University Hospital and University of Turku, 20521 Turku, Finland.
Radiation protection dosimetry
|October 11, 2024
概括
在CT扫描中对患者进行屏蔽可以在某些扫描仪上意外增加胎儿辐射剂量. 仔细考虑屏蔽放置和CT扫描仪模型对于怀孕期间的辐射安全至关重要.
科学领域:
- 医疗成像医学成像
- 辐射物理学 辐射物理学
- 辐射保护 辐射保护
背景情况:
- 计算机断层扫描 (CT) 对于诊断肺部疾病至关重要.
- 患者屏蔽用于减少辐射剂量,但其在CT肺血管造影期间的有效性需要评估,特别是在胎儿剂量方面.
- 外平面屏蔽放置,在定位器中可见,但在扫描范围之外,为剂量评估提供了一个独特的场景.
研究的目的:
- 评估外平面患者屏蔽在CT肺血管造影期间对胎儿辐射剂量的影响.
- 调查不同CT扫描仪模型和协议中屏蔽效率的变化.
主要方法:
- 使用了一个具有假体怀孕腹部的人类形象幻影.
- 在各种CT扫描仪 (西门子,佳能,GE) 上使用临床协议扫描了幻影.
- 使用放射光发光剂量计 (GD-352 M) 测量辐射剂量.
主要成果:
- 在Siemens Somatom go.Up,Canon Aquilion Prime SP和Canon Aquilion One扫描仪上,外平面屏蔽使胎儿剂量减少了3.9%-39.4%.
- 屏蔽使GE Optima的胎儿剂量增加了100%,而Canon Aquilion One和GE Optima扫描仪的腹部剂量增加了17.5%-36.4%.
- 屏蔽对胎儿剂量的影响因CT扫描仪的制造和型号而异,特别是管电流调制.
结论:
- 在特定扫描仪模型上,外平面屏蔽的放置可以在CT肺血管造影中增加胎儿辐射剂量.
- 扫描仪依赖的效应,特别是管电流调制,需要仔细的协议优化.
- 放射学专业人员必须意识到在使用外平面屏蔽时可能会增加剂量.
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