甲亢患者碘治疗后^(131)I滞留量与周围剂量当量率的关系

Study on retained body activity and external dose rate of patients receiving ^(131)I therapy for hyperthyroidism

为实现通过测量患者周围剂量当量率间接估算出其体内131I活度滞留量,建立了甲亢患者体内131I滞留量与周围剂量当量率的关系函数。选取68例甲亢患者,测量患者服碘后0.5 h、4 h、8 h、24 h、48 h、72 h、96 h、120 h、144 h和192 h时距离患者0.3 m、0.6 m、1 m和2 m处的周围剂量当量率;同时收集患者服碘后上述各时间段的全部尿液,测量患者尿液中131I放射性活度,估算出患者的体内131I活度滞留量。拟合得到患者体内131I活度滞留量(Y,单位MBq)与1 m处周围剂量当量率(X,单位μSv/h)的关系为函数Y=22.8X+3.3。医护人员可以通过测量患者1 m处的周围剂量当量率估算出患者的体内131I活度滞留量,该法方便快捷,能够极大降低周围人群的受照剂量,从而对医护人员进行有效的防护。

This study established the function of the retained body activity and the external dose rate of patients treated by 131I. The retained body activities of patients can be estimated by the external dose rate based on this function. The external dose rate and retained body activity of sixty-eight patients were measured. The external dose rate was measured at 0.5 h, 4 h, 8 h, 24 h, 48 h, 72 h, 96 h, 120 h, 144 h and 192 h after the administration with distances of 0.3 m, 0.6 m, 1 m, and 2 m, respectively, with the urine received at the same time for the calculation of the retained body activity. The function of them is Y=22.8X＋3.3; Y stands for the retained body activity （MBq）, X stands for the external dose rate of patient at lm （μSv/h）. This study is beneficial for radiation safety decision-making.