医用诊断X射线的能量分布和能量表达

Energetic distribution and expression for diagnostic X-rays

目的:医学诊断X射线的能量是连续分布的,在开展诊断X射线质量控制中应当采用正确的能量表达方式。方法:在分析X射线产生机制的基础上以管电压为80kV、100kV、120kV的钨靶和30kV的钼靶为例,给出其能量分布形态,同时给出半值层、等效能量、平均能量等3种能量表达方式。结果:用半值层法表达诊断X射线时,应指明第一半值层、第二半值层、同质系数以及附加说明峰值管电压、过滤材料和厚度。结论:诊断X射线的能量的连续性带来表达和理解线束能量的复杂性,在实际工作中应根据需要和能力做出选择。

Objective： To reveal the characteristics of continuous energy of the diagnostic X-rays and its energetic expressions. Methods： The energetic distribution and expressions of three forms of HVL effective energy and mean energy were shown for the examples of 80 100 120kV of X-ray-tube voltages for the tungsten target and 30kV molybdenum target on the base of the mechanism of X-rays. Results： It is necessary to indicate the HVL ratio of HVL1/HVL2 tube- voltage and filtration were given to express the diagnostic energy. Conclusion： The complicity and continues of energetic distribution of the diagnostic X-rays were considered for the choice of energetic expression in the practical applications.