动态楔形板与物理楔形板剂量学的比较研究

Comparison of Dosimetry between Dynamic Wedge and Physical Wedge

目的:比较动态楔形板与物理楔形板剂量曲线分布的特点;方法:用二维电离室矩阵分别测量动态楔形板Y1-IN方向15°,30°,45°,60°;固定楔形板IN方向15°,30°,45°,60°,得到相应楔形野的注量图;Dose1剂量仪测量相同楔形角的动态楔形板与物理楔形板5cm深度的绝对剂量值;结果:相同楔形角的动态楔形板和物理楔形板的楔形曲线大致重合,同深度相同角度的动态楔形板比物理楔形板的绝对剂量值大15%～25%;结论:动态楔形板完全可以替代物理楔形板,提高工作效率和机器使用率。

Objective： To compare the characteristic of dose curver between dynamic wedge and physical wedge. Methods： The Y1-IN direction 15°, 30°, 45°, 60° of dynamic wedge and the IN direction 15°, 30°, 45°, 60° of static wedge were measured with two-dimensional ion chamber array. And the fluence map of wedge field were got. The absolute dose value of 5 cm in depth of dynamic wedge and physical wedge were measured with dosel meter. Results： The wedge curve of dynamic wedge and physical wedge were approximately the same in the condition of same wedge angle. The absolute dose value of dynamic wedge was 15% -25% bigger than that of physical wedge in the condition of same depth and angle. Conclusion： The physical wedge can be completely replaced by dynamic wedge. This can improve working effeciency and utilization rate of machines.