Technegas肺通气显像中医务人员的辐射剂量水平监测与评价  

Monitoring and evaluation of occupational radiation dose during Technegas lung ventilation imaging

作　　者：李蓓蕾[1] 姚之丰[2] 陈绍亮[1] 

机构地区：[1]复旦大学附属中山医院核医学科,上海200032 [2]复旦大学附属肿瘤医院核医学科,上海200032

出　　处：《复旦学报（医学版）》2008年第2期232-235,共4页Fudan University Journal of Medical Sciences

摘　　要：目的监测锝气体(Technegas)发生器使用和肺通气显像采集过程中,医务人员接受的外、内照射剂量水平和方法。方法20例锝气体(Technegas)肺通气显像,制备Technegas平均使用高锝(99mTc)酸钠注射液419MBq(370～555MBq)。测定医务人员在加样、给药过程中手套、口罩上沾染的放射性活度,以及接受的外照射当量剂量率。测定6例医务人员口罩和口罩内侧特制面罩上沾染的放射性活度,推测一次性医用口罩对Technegas颗粒的阻挡能力。根据Technegas药代动力学和内照射剂量的有关数据,计算肺内放射性颗粒沉积量,以及由此造成的肺部吸收剂量和有效剂量。结果一次Technegas肺通气检查过程中,医务人员向石墨坩埚中添加高锝酸钠注射液时手套上的放射性活度为(112.41±272.41)kBq,给患者吸入锝气体时手套上沾有的放射性活度为(6.95±6.15)kBq,整个操作过程中口罩上的放射性活度为(3.13±2.00)kBq。医务人员操作Technegas发生器时接受的外照射累积剂量为(0.69±0.31)μSv,其中最高当量剂量率来自向石墨坩埚中添加高锝酸钠注射液,为(34.25±38.24)μSv/h。一次性口罩对Technegas颗粒的阻挡率达到(85.05±5.65)%。平均有(0.60±0.61)kBqTechnegas颗粒沉积在肺内,造成肺部吸收剂量(0.058±0.059)μGy,有效剂量(0.0096±0.0098)μSv。结论医务人员在整个Technegas发生器使用过程中接受的外照射剂量低。根据"ICRP60"提出放射性工作者平均5年内接受外照射有效剂量<20mSv/a计算,医务人员年操作Technegas发生器可达20000次以上。医务人员在整个Technegas发生器使用过程中接受的内照射剂量低。根据放射性工作者吸入99mTc标记化合物的年摄入量限值(ALI)为2000MBq,医务工作者在佩戴口罩前提下,操作Technegas发生器的次数可达无限多。Objective To measure and evaluate both the external and internal radiation dose for operator exposed to Technegas examination.Methods Twenty Technegas ventilation scintygraphies were performed with the mean charge of ^99mTc-pertechnetate solution of 419 MBq（range 370-550 MBq）.During the filling of the carbon crucible and administering Technegas,the ^99mTc activities on gloves and mouthmask,and dose rate were measured.During 6 examinations,the operator wore a special mouthmask while administering Technegas.Radioactivity on the mask was measured to test the capacity of adsorption of the mouthmask.On the basis of pharmacokinetic data and internal radiation dose of Technegas we got in former research,the percentage of radioactivity deposited in the lungs,the absorption dose of lungs and the effective dose were calculated.Results The activity on the gloves worn during the filling of the crucible with generator eluate and during administration of the gas,and on the mask worn by the operator during the whole study was（112.41±272.41）kBq,（6.95±6.15）kBq and（3.13±2.00）kBq,respectively.Total body dose of operator from external radiation during the adaptation of the Techneas apparatus was（0.69±0.31）μSv.The highest dose rate was（34.25±38.24）μSv/h during the filling of the crucible with generator eluate.The mouthmask used to stop the Technegas particles was found to retain 85.05%±5.65%.The assumption of（0.60±0.61）kBq deposited in the lungs gave absorption dose of（0.058±0.059）μGy,effective dose of（0.009 6±0.009 8）μSv,respectively.Conclusions The external radiation dose during operation of a Technegas generator was very low.With a whole body dose of 0.69 μSv per examination,an operator can perform up to 20 000 examinations a year without exceeding the permitted average annual dose published as ICRP 60 standard.The internal radiation dose during operation of a Technegas generator is very low.An operator may perform an almost unlimited number of Technegas studies before reaching the

关 键 词：锝气体 肺通气显像 辐射剂量 

分 类 号：R817.4[医药卫生—影像医学与核医学]