【摘要】 目的探讨和分析现行国家标准GBZ/T 144-2002光子外照射剂量转换系数的局限性,以期为其更新提供一些参考。方法将国家标准GBZ/T 144-2002和ICRP 116号出版物剂量转换系数比较。结果二者剂量转换系数(D_T/Ka)整体变化趋势一致,但是肝脏左侧位照射时,ICRP 116号出版物女性、男性剂量转换系数高于GBZ/T 144,能量小于150 keV时,相对变化可超过30%;除了右侧位照射以外,ICRP 116号出版物女性剂量转换系数高于男性,能量在30~200 keV,左侧位照射相对变化超过30%,能量越低差异越大,最大超过100%。女性乳腺前后位照射能量高于4 MeV时,相对变化超过50%。结论不同照射条件下,GBZ/T 144-2002与ICRP 116号出版物器官剂量转换系数的变化趋势相一致,但是当考虑参考体模类型及参考人参数、性别、次级电子以及入射光子能量等时差异较明显,GBZ/T 144需要稍作调整。更多还原

【Abstract】 Objective To explore and analyze the limitations of the dose conversion coefficients of the current national standard GBZ / T144- 2002 external photon irradiation,in order to provide some reference for its update. Methods Compare the dose conversion coefficients of the national standard GBZ / T144- 2002 with the International Commission on Radiological Protection( ICRP) 116 and analyze the differences. Results The overall change trends of the two dose conversion coefficients are consistent,however,the left lateral geometry of the liver radiation,dose conversion coefficients of the ICRP 116 for females and males are higher than GBZ / T144,when the energy is less than 150 keV,the relative changes can be more than 30%; in addition to the right lateral geometry,dose conversion coefficients of the ICRP 116 for females are higher than males;the energy from 30 keV to 200 keV,the relative changes of the left lateral geometry in radiation are more than 30%,the lower the energy,the greater the difference,the largest is more than 100%. The antero- posterior geometry radiation of the female breasts,the energy higher than 4 MeV,the relative changes are more than 50%. Conclusion Under different radiation conditions,the national standard is consistent with the results of ICRP 116,but when considering the type of reference phantom and reference persons’ parameters,gender,secondary electron,incident photon energy and so on,the difference is obvious and the dose conversion coefficients of the GBZ / T144 need to make some adjustments.更多还原