摘要
目的研究各种条件下的体位固定材料在不同能量X射线路径上对放射治疗患者吸收剂量和体表剂量的影响,为临床放射治疗计划设计提供参考依据。方法在专用模体中,用电离室测量不同能量下,模体上添加各种体位固定材料前后剂量的变化,得到体位固定材料在不同能量X射线路径上对放射治疗患者吸收剂量和体表剂量的影响。结果添加体位固定材料后使放射治疗患者的吸收剂量减少,随着X射线能量的增加固定材料对放射治疗患者吸收剂量的影响变小;同一能量,有机玻璃对吸收剂量的影响最大,面膜、真空袋、碳纤维对吸收剂量的影响较小。不同厚度的面膜、真空袋对表面剂量影响不同,厚度越大,影响越大;面膜孔径越大对表面剂量影响越小。结论体位固定材料在X射线路径上对放射治疗患者吸收剂量和体表剂量有较大的影响,在治疗计划设计过程中应根据临床要求,进行补偿修正。
Objective To investigate the impacts of position fixing material on absorption dose and surface dose under various conditions in patients who accept radiotherapy , and to provide some references for the design of clinical radiotherapy plan .Methods Ion chamber was used to measure the doses before or /and after adding different position fixing material on the specific pattern , and to get the variation of the doses in different energy X-ray with different illumination path in radiotherapy patients .Results The absorption dose decreased in radiotherapy patients after adding position fixing material.With the increasing of X-ray energy,the effect of adding position fixing material on the absorption dose in radiotherapy patients became less .In the same energy condition ,organic glass absorbed the largest amount of dose compared with face membrane ,vacuum bag and carbon fire .The face membranes of different thicknesses had various impacts on surface dose ,so did the vacuum bags of different thicknesses .The thicker one impacted more . Especially for face membranes , the one with larger aperture had less impacts on surface dose .Conclusion In the process of making plan ,the relative dose should be compensated since position fixing material has a significant effect on absorption dose and surface dose .
出处
《广西医学》
CAS
2014年第6期767-769,共3页
Guangxi Medical Journal
关键词
放射治疗
体位固定材料
吸收剂量
体表剂量
Radiotherapy
Position fixing material
Absorption dose
Surface dose
