某医院粒籽源永久性植入治疗病房的剂量监测结果分析

Analysis of dose monitoring results of the ward for permanent seed source implantation treatment in a hospital

目的研究某医院粒籽源永久性植入治疗病房内的外照射剂量水平和分布情况,对其辐射风险进行评估,为加强粒籽源永久性植入治疗放射工作人员的放射防护与监督提供科学依据,同时提出合理化的辐射防护建议。方法采用热释光剂量测量方法对粒籽源永久性植入治疗病房内10类区域的剂量水平进行为期1年的监测,并结合病人植入粒籽源数目和住院天数进行剂量分析。结果该病区一年内共收住病人1232人次,其中行粒籽源永久性植入治疗病人432人次(190人),共植入粒籽源2.746843×10^(11) Bq(7423.9 mCi),人均6.3566×10^(8) Bq(17.18 mCi),粒籽源永久性植入治疗病人年度住院天数2478天,平均住院6天。热释光剂量监测结果表明,各监测点处的剂量范围为0.23~13.94 mSv,均值为3.37 mSv,中值为1.90 mSv。其中病床两侧和输液架处的剂量范围明显高于其他点位处,经剂量/活度和剂量/(活度·天)分析,其差异依旧存在,均存在统计学差异。结论该粒籽源永久性植入病房内存在外照射剂量偏高的点位,医护人员和陪护人员应减少在此点位居留的时间或远离此点位。医护人员年度个人剂量监测结果远低于国家标准要求,亦低于本次实验点位剂量监测结果,与医护人员的实际工作和居留情况有关。工作人员在穿戴防护用品的情况下,在剂量安全范围内,可适当增加粒籽植入活度和住院天数。患者在术后穿戴防护,可明显降低其对医护人员的外照射剂量。

Objective To study the external radiation dose level and distribution in the ward for permanent seed source implantation treatment in a hospital, and evaluate its radiation risk, so as to provide scientific basis for strengthening the radiation protection and supervision of radiation workers in permanent implantation therapy. At the same time, reasonable suggestions for radiation protection are put forward. Methods The thermoluminescence dosimetry was used to monitor the dose levels of different areas of the ward for permanent seed source implantation treatment for a period of one year, The areas included 10 types of regions in Inpatient Ward. The dose analysis was carried out according to the number of implanted seeds and the days of hospitalization. Results During the period of one year, a total of 1 232 patients were admitted to the ward, of which 432(190) were treated with permanent implantation of seed source, with a total activity of 2.746 843 ×10^(11) Bq(7 423.9 mCi), and an average of 6.356 6 × 10^(8) Bq(17.18 mCi) per capita of seed source implanted. The annual hospitalization days of patients treated with permanent seed source implantation were 2 478 days, with an average of 6 days. The results of thermoluminescence dose monitoring showed that the dose range of each monitoring point was 0.23 mSv^13.94 mSv, the average value was 3.37 mSv, and the median value was 1.90 mSv. Among them, the dose range on both sides of the bed and at the infusion rack was significantly higher than that at other points. By dose/activity and dose/(activity · day)analysis, there were statistical differences. Conclusion There is a point where the external radiation dose is on the high side in the ward for permanent seed source implantation treatment, and the medical staff and accompanying staff should reduce the time of staying at this point or stay away from this point.The annual personal dose monitoring results of medical staff are much lower than the requirements of national standards, and also lower than the results of this experimental site dose monitoring, which is related to the actual work and residence of medical staff.When workers wear protective equipment, within the safe range of dose, the seed implantation activity and average hospital stay can be increased appropriately. Patients wearing protection after operation can significantly reduce their external radiation dose to medical staff.