Study On Retained Body Activity And Ambient Dose Equivalent Rate Of Patients Receiving ¹³¹I Therapy For Hyperthyroidism

This study established the function of the retained body activity and the ambient dose equivalent rate of patients treated by 131I. The retained body activities of patients can be estimated by the ambient dose equivalent rate at any distance and at any time based on this function. The ambient dose equivalent rate and retained body activity of sixty-eight patients were measured. The ambient dose equivalent rate was measured at 0.5h,4h,8h,24h,48h, 72h,96h,120h,144h and 192h after the administration with distances of 0.3m,0.6m, lm, and 2m, respectively, the urine was received at the same time which was used to calculate the retained body activity. The function of the retained body activity and the external dose rate of patient at 1m is Y=(22.8±0.2)X+(3.3±0.9); the function calculated by the data of the whole body counter is Y=(20.6±0.3)X+(1.3±0.6).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. Medical personnel can calculate the retained body activity by measuring the ambient dose equivalent rate of patients at distance of 1m.Thus, medical personnel can make protection suggestions for medical care people, the public and family and determine whether to allow patients to leave the hospital in accordance with national standards. This study also provide for formulation or revision of the relevant national standards with reliable data and feasible operating method.