甲状腺显像疏/甲比预测^(131)I治疗Graves病后甲状腺功能减退症

Sparse location radioactive counts/radioactive counts in thyroid area in predicting hypothyroidism after radioiodine therapy in patients with Graves disease

目的探讨99mTcO4-甲状腺显像中甲状腺内稀疏部位平均放射性计数与整个甲状腺内平均放射性计数的比值(疏/甲比)与Graves病(GD)131I治疗后甲状腺功能减退症(简称甲减)的关系。方法对172例经131I治疗的GD患者于治疗前进行99mTcO4-甲状腺显像,并计算其疏/甲比。根据治疗效果将患者分为痊愈组、甲减组和未愈组。用ROC曲线确定疏/甲比的诊断阈值,分析疏/甲比与治疗后甲减的关系。结果取疏/甲比0.92为诊断甲状腺内存在稀疏部位的临界值,其灵敏度为0.86,特异度为0.65。甲减组与痊愈组、未愈组的疏/甲比差异均有统计学意义(P<0.05)。疏/甲比<0.92时,治疗后甲减发生率高。结论疏/甲比与131I治疗后GD患者发生甲减有相关性,疏/甲比<0.92时,甲减发生率高。

Objective To explore the relationship between the specific value of sparse location radioactive counts/radioactive counts in thyroid area（S/T） of 99mTcO4-thyroid imaging and hypothyroidism following 131I treatment in patients with Graves disease（GD）.Methods 99mTcO4-thyroid imaging were performed for all of 172 patients with GD before radioiodine therapy,and the value of S/T of each imaging was measured.The patients were divided into recovery group,hypothyroidism group and non-recovery group according to curative effect after 1 year＇s following up.The diagnostic cut-off value of S/T was confirmed with ROC curve,then the relationship between S/T and hypothyroidism after treatment was assessed.Results ROC curve analysis showed the best diagnostic cut-off value of S/T was 0.92,and the responding sensitivity and specificity was 0.86 and 0.65,respectively.The difference of S/T was statistically significant between hypothyroidism group and recovery group,as well as between hypothyroidism group and non-recovery group（P0.05）.S/T0.92 was associated with high incidence rate of hypothyroidism after radioiodine therapy.Conclusion There are some relativities between the S/T and hypothyroidism after 131I treatment in patients with GD.The incidence of hypothyroidism increases when S/T0.92.