目的 尽管放射性碘（131I）治疗Graves病（Graves’ Disease, GD）已经有较长时间的经验，但如何确定一个最佳的放射性活度以尽快控制甲亢症状，仍然是目前讨论的焦点。本文旨在研究两组不同放射性活度的甲亢患者的临床治疗效果。方法 回顾性研究我科诊断为GD并行放射性碘（131I）治疗的患者147例，根据131I活度不同，将患者分为低放射性活度组G1(〈3.7 MBq/mL)和高放射性活度组G2(〉4.44 MBq/mL)两组，并观察治疗后一年随访结果。结果 G1及G2两组患者的治愈率分别为48%或94.8%。G1及G2间的治愈率、复发率存在显著差异。结论 放射性碘用于治疗GD，高放射性活度比低放射性活度更有利于控制甲亢。因此我们推荐较高放射性活度用于GD患者。

Objective Despite the long experience in using radioiodine for treatment of the Graves' disease (GD), controversy still remains regarding the method to determine the optimal dose to achieve quick control of hyperthyroidism. The aim of this study was to examine the clinical outcome of 131I therapy with two different activities for patients. Methods We carried out a retrospective study to compare the therapeutic efficacy of two different 131I activities between <3.7 MBq/mL and >4.44 MBq/mL in 147 Graves' disease patients after a one-year follow-up period. Diagnosis of Graves’ disease was confirmed in patient’s hyperthyroidism symptoms and biochemical thyroid function tests, and met the following additional criteria, such as diffusely enlarged thyroid gland without palpable nodules and an elevated uptake of radioiodine by the gland. Results Overall 48.0% or 94.8% of the patients had successful treatment outcome in the two groups that were subjected to lower and higher radioactivity, respectively. The cure rate including both euthyridism and hypothyroidism incidence rate (confirmed by serum TSH and free T3/free T4)). There was significant difference of outcome in the cure rate and the reduced rate of thyroid volume between the lower and higher activities of radioiodine groups. Conclusion Radioiodine higher than 4.44 MBq/mL was found to be more effective than dosage less than 3.7 MBq/mL in managing patients with Graves' disease. The higher activity (4.44-5.18 MBq /mL) should be routinely used in patients.