Dose inter-comparison studies for Co γ-ray and 10 MeV electron beam irradiation were carried out 60 from July to October in 2002. The purpose of the studies was to check the reliability of the alanine-PE film dosime-...Dose inter-comparison studies for Co γ-ray and 10 MeV electron beam irradiation were carried out 60 from July to October in 2002. The purpose of the studies was to check the reliability of the alanine-PE film dosime- ters made by CIAE, which will be used as transfer standard dosimetry system mainly for electron beam irradiation. The expanded uncertainty of CIAE alanine/EPR dosimetry system was 4.1% for doses not higher than 10 kGy and 5.4% for those above 10 kGy (k=2). CIAE alanine-PE film dosimeters were sent to JAERI, RISO (National Labora- tory in Denmark) and INCT respectively, which were irradiated by Co gamma-rays or electron beams in each labo- 60 ratory. The irradiated dosimeters were then sent back to CIAE for electron paramagnetic resonance (EPR) analysis. The agreements were obtained to be ±1.9% for gamma-ray dose measurement and ±4.3% for electron beam dose measurement, which were all within the combined uncertainty of the reference and CIAE alanine/EPR dosimetry system. Furthermore, the overall mean ratio was found to be 0.995 with 1.8% in the coefficient of variation (CV). The preliminary inter-comparison studies indicated that CIAE film alanine/EPR dosimetry system had the potential to be used as a transfer dosimetry system for high dose measurement.展开更多
目的:比较碳离子二维放射治疗(two-dimensional carbon-ion radiotherapy,2D-CIRT)计划与光子容积调强放射治疗(volume modulated arc therapy,VMAT)计划在Ⅲ期非小细胞肺癌中剂量学优劣,为临床碳离子治疗提供依据。方法:选取我中心13...目的:比较碳离子二维放射治疗(two-dimensional carbon-ion radiotherapy,2D-CIRT)计划与光子容积调强放射治疗(volume modulated arc therapy,VMAT)计划在Ⅲ期非小细胞肺癌中剂量学优劣,为临床碳离子治疗提供依据。方法:选取我中心13例Ⅲ期非小细胞肺癌患者,使用相同的处方剂量及危及器官约束条件,分别在Ciplan计划系统上设计2D-CIRT计划和Eclipse计划系统上设计VMAT计划,比较剂量-体积直方图,评价靶区剂量分布及危及器官受量。采用SPSS 22.0软件进行数据分析。结果:CIRT和VMAT计划肿瘤覆盖率均较好,PTV1的D_(98)、D_(95)、D_(50)差异无统计学意义,两种计划的均匀性指数(homogeneity index,HI)相似(CIRT与VMAT:0.39 Gy与0.38 Gy,P>0.05)。PTV2两种方案在D_(95)、D_(98)、D_(50)、D_(2)均有显著性差异,PTV2采用CIRT的HI也明显优于VMAT(CIRT vs VMAT:0.08 Gy vs 0.16 Gy,P=0.003)。与光子VMAT相比,CIRT计划中健侧肺的V_(5)、V_(10)、V_(20)、V_(30)、V_(40)和D_(mean)明显降低。患侧肺中CIRT的V_(5)低于VMAT(CIRT vs VMAT:53.00 vs 64.41,P=0.003),V_(10)、V_(20)、V_(30)、V_(40)、D_(mean)两种计划均无统计学差异;CIRT有较低的脊髓D max(CIRT vs VMAT:18.61 Gy vs 43.03 Gy,P=0.000)、食管D_(mean)(CIRT vs VMAT:16.25 Gy vs 20.38 Gy,P=0.031)和V_(5)0(CIRT vs VMAT:4.49 Gy vs 11.43 Gy,P=0.005)、骨V_(10)和V_(30),以及气管和支气管树的V_(5)0。结论:与光子VMAT相比,2D-CIRT被动束流扫描技术在Ⅲ期非小细胞肺癌治疗中显著降低了对危及器官的辐射剂量,对正常组织有更好的保护作用。展开更多
目的:提高放射治疗剂量控制水平,加强放射治疗中的质量保证,配合2009年IAEA/WHO世界范围内,中国片区(中国四川)放射治疗机输出剂量的(TLD)剂量比对进行本次核查。方法:采用LiF(Mg,Cu,P)TLD剂量计,在5cm水深处、10 x 10cm照射野,SSD和SA...目的:提高放射治疗剂量控制水平,加强放射治疗中的质量保证,配合2009年IAEA/WHO世界范围内,中国片区(中国四川)放射治疗机输出剂量的(TLD)剂量比对进行本次核查。方法:采用LiF(Mg,Cu,P)TLD剂量计,在5cm水深处、10 x 10cm照射野,SSD和SAD照射,对我省20个地、市、县34家医疗单位的放射治疗机的输出量进行比对。结果:13台^(60)Co放射治疗机合格11台,合格率占84.6%。21台加速器合格18台,合格率占85.7%。结论:本次我省放疗单位放射治疗机输出剂量比对合格率低于发达国家水平,高于全国调查平均水平。展开更多
文摘Dose inter-comparison studies for Co γ-ray and 10 MeV electron beam irradiation were carried out 60 from July to October in 2002. The purpose of the studies was to check the reliability of the alanine-PE film dosime- ters made by CIAE, which will be used as transfer standard dosimetry system mainly for electron beam irradiation. The expanded uncertainty of CIAE alanine/EPR dosimetry system was 4.1% for doses not higher than 10 kGy and 5.4% for those above 10 kGy (k=2). CIAE alanine-PE film dosimeters were sent to JAERI, RISO (National Labora- tory in Denmark) and INCT respectively, which were irradiated by Co gamma-rays or electron beams in each labo- 60 ratory. The irradiated dosimeters were then sent back to CIAE for electron paramagnetic resonance (EPR) analysis. The agreements were obtained to be ±1.9% for gamma-ray dose measurement and ±4.3% for electron beam dose measurement, which were all within the combined uncertainty of the reference and CIAE alanine/EPR dosimetry system. Furthermore, the overall mean ratio was found to be 0.995 with 1.8% in the coefficient of variation (CV). The preliminary inter-comparison studies indicated that CIAE film alanine/EPR dosimetry system had the potential to be used as a transfer dosimetry system for high dose measurement.
文摘目的:比较碳离子二维放射治疗(two-dimensional carbon-ion radiotherapy,2D-CIRT)计划与光子容积调强放射治疗(volume modulated arc therapy,VMAT)计划在Ⅲ期非小细胞肺癌中剂量学优劣,为临床碳离子治疗提供依据。方法:选取我中心13例Ⅲ期非小细胞肺癌患者,使用相同的处方剂量及危及器官约束条件,分别在Ciplan计划系统上设计2D-CIRT计划和Eclipse计划系统上设计VMAT计划,比较剂量-体积直方图,评价靶区剂量分布及危及器官受量。采用SPSS 22.0软件进行数据分析。结果:CIRT和VMAT计划肿瘤覆盖率均较好,PTV1的D_(98)、D_(95)、D_(50)差异无统计学意义,两种计划的均匀性指数(homogeneity index,HI)相似(CIRT与VMAT:0.39 Gy与0.38 Gy,P>0.05)。PTV2两种方案在D_(95)、D_(98)、D_(50)、D_(2)均有显著性差异,PTV2采用CIRT的HI也明显优于VMAT(CIRT vs VMAT:0.08 Gy vs 0.16 Gy,P=0.003)。与光子VMAT相比,CIRT计划中健侧肺的V_(5)、V_(10)、V_(20)、V_(30)、V_(40)和D_(mean)明显降低。患侧肺中CIRT的V_(5)低于VMAT(CIRT vs VMAT:53.00 vs 64.41,P=0.003),V_(10)、V_(20)、V_(30)、V_(40)、D_(mean)两种计划均无统计学差异;CIRT有较低的脊髓D max(CIRT vs VMAT:18.61 Gy vs 43.03 Gy,P=0.000)、食管D_(mean)(CIRT vs VMAT:16.25 Gy vs 20.38 Gy,P=0.031)和V_(5)0(CIRT vs VMAT:4.49 Gy vs 11.43 Gy,P=0.005)、骨V_(10)和V_(30),以及气管和支气管树的V_(5)0。结论:与光子VMAT相比,2D-CIRT被动束流扫描技术在Ⅲ期非小细胞肺癌治疗中显著降低了对危及器官的辐射剂量,对正常组织有更好的保护作用。
文摘目的:提高放射治疗剂量控制水平,加强放射治疗中的质量保证,配合2009年IAEA/WHO世界范围内,中国片区(中国四川)放射治疗机输出剂量的(TLD)剂量比对进行本次核查。方法:采用LiF(Mg,Cu,P)TLD剂量计,在5cm水深处、10 x 10cm照射野,SSD和SAD照射,对我省20个地、市、县34家医疗单位的放射治疗机的输出量进行比对。结果:13台^(60)Co放射治疗机合格11台,合格率占84.6%。21台加速器合格18台,合格率占85.7%。结论:本次我省放疗单位放射治疗机输出剂量比对合格率低于发达国家水平,高于全国调查平均水平。