二维电离室阵列在调强放疗剂量验证中的应用

Application of 2D Ionization Chamber Array in Dose Verification of Intensity Modulated Radiotherapy

目的:通过测量加速器X射线射野,评估二维电离室阵列MatriXX的剂量学特性,为调强放疗计划的剂量验证提供依据。方法:用MatriXX测量X射线射野,研究其剂量、重复性;用计算和测量相比对的方法,研究MatriXX测量多叶光栅射野的平面剂量分辨率。结果:除了射野边缘外,MatriXX有良好的剂量学特性。结论:MatriXX可用于调强放疗计划的剂量验证,对于剂量梯度较大区域的剂量验证需要进一步研究。

Objective:To investigate the dose characteristics of the MatriXX by measurement under X-ray of the accelerator,it is the foundation of dose verification of the intensity modulated radiation therapy(IMRT).Methods:It is to investigate the dose linearity,reproducibility by measurement of the X-ray fields,to investigate the planar dose resolution of multileaf collimator fields by comparison of measurement and calculation.Results:In addition to the edge of the field,MatriXX has good dose characteristics.Measurement is good consistent with calculation in large fields,it is less consistent in field edge and large dose gradient region.Conclusion:It is suitable to verify the IMRT dose distribution by MatriXX,but it needs more researches for the large dose gradient region.