Title: Monte Carlo-based estimation of patient absorbed dose in 99mTc-DMSA, -MAG3, and -DTPA SPECT imaging using the University of Florida (UF) phantoms Show Chinese title

Title: 基于蒙特卡罗方法的99mTc-DMSA、-MAG3和-DTPA SPECT成像中患者吸收剂量的估算，使用佛罗里达大学（UF）体模

Abstract: SPECT imaging is one of the common modalities used to examine kidney disease. The radiopharmaceuticals such as 99mTc-MAG3, 99mTc-DTPA, and 99mTc-DMSA are commonly employed for pediatric patients. It is generally accepted that children organs are more sensitive to radiation than adults, due to their growth rate. Therefore, evaluating the absorbed dose in children to avoid irrecoverable damage is highly crucial. In this work, absorbed dose by different organs of children within the SPECT imaging for the above-mentioned radiopharmaceuticals were estimated through the use of Monte Carlo simulation for patients at the ages of 4, 8, 11, and 14-years old. The patients absorbed dose was estimated based on the specific radiopharmaceutical uptake patterns and the age-related human body models. To this end, we used the University of Florida (UF) voxel-wise baby phantoms and the Monte Carlo simulation for the pediatric patients at 4, 8, 11, and 14 years of age. The accuracy of the dosimetric outcomes was evaluated versus the ICRP 128 data. The highest and lowest doses absorbed by the kidneys were 0.48 mGy-MBq and 0.0042 mGy-MBq obtained for 4-year-old and 14-year-old children using 99mTc-DMSA and 99mTc-MAG3 radiopharmaceuticals, respectively. Moreover, in these cases, the relative errors of simulation results compared to the reference ICRP data were 12.1% and 0.95%, respectively. The simulation results were in good agreement with the ICRP 128 data. The results showed that the highest absorbed dose was by kidneys and when 99mTc-DMSA was used. The highest and lowest absorbed dose in the organs occurs when 99mTc-DMSA and 99mTc-MAG3 (in normal renal function) are used, respectively. On the other hand, the results indicated that the dose received by the organs decreases with age. Show Chinese abstract

Abstract: 单光子发射计算机断层扫描（SPECT）成像是用于检查肾脏疾病的一种常用模式。 如99mTc-MAG3、99mTc-DTPA和99mTc-DMSA等放射性药物常用于儿童患者。 通常认为，由于生长速度的原因，儿童的器官对辐射更敏感。 因此，评估儿童吸收的辐射剂量以避免不可逆损伤是非常重要的。 在本研究中，通过使用蒙特卡罗模拟，估算了上述放射性药物在4岁、8岁、11岁和14岁患者的SPECT成像中不同器官的吸收剂量。 患者的吸收剂量是基于特定的放射性药物摄取模式和与年龄相关的体模进行估算的。 为此，我们使用了佛罗里达大学（UF）的体素婴儿体模和4岁、8岁、11岁和14岁儿童的蒙特卡罗模拟。 将剂量学结果的准确性与ICRP 128数据进行了比较。 使用99mTc-DMSA和99mTc-MAG3放射性药物分别获得4岁和14岁儿童的肾脏吸收最高和最低剂量，分别为0.48 mGy-MBq和0.0042 mGy-MBq。 此外，在这些情况下，与参考ICRP数据相比，模拟结果的相对误差分别为12.1%和0.95%。 模拟结果与ICRP 128数据高度一致。 结果表明，最高吸收剂量来自肾脏，并且当使用99mTc-DMSA时达到最高值。 当使用99mTc-DMSA和99mTc-MAG3（在正常肾功能情况下）时，器官中的最高和最低吸收剂量分别出现。 另一方面，结果表明，器官接受的剂量随着年龄的增长而减少。