摘要
目的:研究医用直线加速器外挂式物理楔形板的质量控制方法,对物理楔形板的剂量分布进行测量和分析,提高放射治疗精度。方法:利用指型电离室测量参考点处(固体水下5 cm)的点剂量,并与治疗计划系统(treatment planning system,TPS)的计算结果进行对比。利用二维矩阵电离室测量固体水下5 cm的平面剂量分布,用点剂量的测量结果校正后,与TPS的计算结果进行Gamma 3 mm/3%分析对比。结果:医用直线加速器加装外挂式物理楔形板后,点剂量实测值与计算值偏差小于1%,二维剂量分布相似度大于95%,可以满足临床放疗精度要求。结论:利用指型电离室和二维矩阵电离室可以方便有效地对外挂式物理楔形板的剂量分布进行测量和分析,适合用于加速器日常质控。
Objective To explore the quality control method for the external physical wedge plate to measure the dose distribution under the physical wedge plate.Methods A finger point ionization chamber was used to measure the point dose at the reference point and the measurements were compared with the calculated results of TPS.The plane dose distribution of 5 cm under water was measured by 2D-matrix chamber,and the results were corrected with the results of point dose measurement,and compared with the calculated results of TPS by Gamma 3 mm/3%analysis.Results The deviation of point dose between measured value and TPS calculation was less than 1%.The similarity of two-dimensional dose distribution was greater than 95%.The result showed that the wedge filter met the requirements of clinical accuracy.Conclusion The finger chamber and 2D-matrix chamber can be used to measure and analyze the external wedge plate conveniently and effectively.This method can be used for daily accelerator quality control.
作者
辛思谕
刘剑华
XIN Si-yu;LIU Jian-hua(Radiotherapy Department,Tumor Hospital of Jilin City,Jilin 132012,Jilin Province,China)
出处
《医疗卫生装备》
CAS
2018年第12期49-51,77,共4页
Chinese Medical Equipment Journal
关键词
医用直线加速器
楔形板
电离室
放射治疗
质量控制
medical linear accelerator
wedge plate
ionization chamber
radiotherapy
quality control
作者简介
辛思谕(1987—),男,硕士,放疗物理师,主要从事放射治疗质控方面的研究工作,E-mail:syxinsyxin@fox mail.com。
