医院SPECT/CT机房工作人员甲状腺、眼晶状体和手部受照辐射水平及其防护研究

Study on exposure levels and protection of the thyroids,eye lenses and hands of technologists in SPECT/CT room of hospital

目的:对单光子发射型电子计算机断层扫描与X射线计算机断层扫描(SPECT/CT)设备机房工作人员甲状腺、眼晶状体和手部的受照剂量及辐射水平进行研究,为评估SPECT/CT机房工作人员受到辐射危害及放射防护提供参考。方法:选取2019年2月至2020年10月中国医学科学院肿瘤医院核医学科在SPECT/CT机房1和SPECT/CT机房2的工作人员各2名,采用光致发光(OSL)剂量计对4名SPECT/CT机房工作人员7个季度的受照剂量进行监测,4名工作人员摆位总量为20 682例患者。工作人员在工作中常规穿戴防护铅衣(0.5 mmPb)和铅围脖(0.5 mmPb)等防护用品,将OSL剂量计分别佩戴在每名机房摆位人员的甲状腺、眼睛附近位置和手部。4名工作人员每人佩戴1套(甲状腺、眼睛附近和手部位置共3枚)OSL剂量计。佩戴OSL剂量计时长为21个月,对甲状腺部位的10 mm深度个人剂量当量[Hp(10)]、眼晶状体部位的3 mm深度个人剂量当量[Hp(3)]和手部的0.07 mm深度个人剂量当量[Hp(0.07)]进行季度监测,评估SPECT/CT机房4名工作人员甲状腺、眼晶状体和手部的受照剂量。4名工作人员均接受常规外照射个人剂量监测。结果:4名工作人员每人年平均摆位例数约2 955例患者,其中仅1名工作人员甲状腺、眼晶状体和手部年平均所受的剂量最高,分别为0.129、0.071和0.151 mSv/a,但远低于放射工作人员剂量约束值5、5和125 mSv/a。结论:SPECT/CT机房4名工作人员为患者摆位时直接接触注射过放射性药物的患者,但其甲状腺、眼睛和手部受照剂量均远低于放射工作人员剂量约束值。按要求合理使用个人防护用品能够有效防护摆位工作中的辐射。

Objective:To study exposure doses and radiation levels of thyroids,eye lenses and hands of technologists who worked in the single-photon emission computed tomography/computed tomography(SPECT/CT)room,so as to provide a reference for assessing radiation hazards and radiation protection of technologists in SPECT/CT machine room.Methods:During February 2019 and October 2020,2 technologists each of two SPECT/CT machine rooms of the department of nuclear medicine of Cancer Hospital,Chinese Academy of Medical Sciences were selected,and the optically stimulated luminescence(OSL)dosimeters were used to monitor the exposure doses of four technologists in the SPECT/CT room in 7 quarters.The total amount that they put positions of patients were 20682 patients.The technologist routinely wore lead aprons(0.5 mmPb)and lead collars(0.5 mmPb)during clinical work.OSL dosimeters were placed on the thyroids,the locations nearby the eyes and hands of each technologist.Each one of 4 technologists wore a set of dosimeters(included three sets for the thyroid,the locations nearby the eye and hand).The monitoring period that technologists wore OSL dosimeters was 21 months.The personal dose equivalent[Hp(10)]of thyroid at 10 mm depth,the personal dose equivalent[Hp(3)]of the location nearby eyes at 3 mm depth,and the personal dose equivalent[Hp(0.07)]of hands at 0.07 mm were monitored as quarter.The exposure doses of the thyroids,eye lens and hands of 4 technologists in SPECT/CT machine room were assessed on the basis of these results of measurements.All four technologists also underwent dose monitor of routine external radiation.Results:The average number of each technologist who put position was approximately 2955 patients.Among of the four technologists,the exposure doses of thyroid,eye lens and hand of only one technologist were highest,which were respectively 0.129,0.071 and 0.151 mSv,while they were far below the constraint values(5,5 and 125 mSv/a)of dose for radiation workers.Conclusion:The four technologists of the SPECT/CT room directly contact with patients who have been injected with radiopharmaceuticals during they put the positions of patients.But,the exposure doses of their thyroid,eye lenses and hands are far below the constraint value of dose for radiation workers.The reasonable use of personal protective equipment as requirement can effectively safeguard against radiation exposure during technologist put position of patient.