甲状腺显像归一化分析在131I治疗Graves甲亢中的价值

摘要

目的 探讨计算机辅助的甲状腺显像归一化分析在131I治疗Graves甲状腺功能亢进症(简称甲亢)中的作用.方法 回顾分析131I治疗的Graves甲亢患者60例,以甲状腺小于35g且没有结节为入组标准.重新调取甲状腺扫描的原始数据,经计算机软件行归一化处理和图像放大.对甲状腺两叶面积比值、放射性计数比值、灰阶比值、呈多中心放射性分布的例数、用药次数和总治疗剂量进行多重线性回归分析(逐步回归法),研究总治疗剂量和用药次数与性别、年龄及上述因素的相关性,并根据临床转归进行分组,分析转归为甲状腺功能(简称甲功)正常和甲功减退(简称甲减)与上述因素的相关性.结果 根据Marinelli公式计算的131I剂量,单次给药甲亢治愈率50％( 30/60),其余患者需要多次给药治疗.除了甲状腺质量和摄碘率外,131I总剂量还和女性(F=4.23,P=0.050)、两叶面积比(F=6.20,P=0.020)、多中心放射性分布(F=5.12,P=0.033)有关.131I治疗次数与两叶灰阶比(F=8.89,P=0.006)和多中心放射性分布(F=4.98,P=0.034)有关.转归为甲功正常组服药剂量与两叶灰阶比(F=10.66,P=0.017)和面积比(F=10.42,P=0.018)相关;而转归为甲减组的影响因素为甲状腺质量(F =7.65,P=0.013)和多中心放射性分布(F=8.01,P =0.011).结论 计算机辅助归一化分析对Graves甲亢治疗计划的制定和预后有一定帮助,对于出现明显的甲状腺两叶放射性分布不均者,应增加剂量和多次治疗;对于放射性分布均匀者,应注意避免剂最增大与甲状腺质量增大呈线性关系,否则甲减概率会增高.%Objective To explore the value of normalization analysis of thyroid scans on 131 I treatment planning for Graves' disease.Methods Patients with hyperthyroidism treated by 131I were retrospectively analyzed.Sixty cases with thyroid glands less than 35 g and without thyroid nodules were enrolled.Raw data of thyroid scans were re-processed using a software for normalization and magnification.Correlation between total dose,the number of treatments and other factors,such as area ratios of bilateral lobes,bilateral radioactive counts,bilateral gray scales and multifocal uptake patterns,were analyzed using step-bystep regression analysis.Correlations between normal thyroid function,hypothyroidism and the abovementioned factors were analyzed using multiple linear regression analysis.Results Fifty percent (30/60) of cases were cured after a single-dose treatment,and the remaining 50％ required multiple treatments.In addition to thyroid mass and radioactive iodine uptake,total dose correlated with gender ( F =4.23,P =0.050 ),area ratio of bilateral lobes ( F =6.20,P =0.020) and multifocal uptake pattern ( F =5.12,P =0.033 ).The number of treatments correlated with ratio of bilateral gray scales ( F =8.89,P =0.006) and multifocal uptake pattern (F =4.98,P =0.034).According to outcomes,patients were divided into a normal thyroid function group and a hypothyroidism group.131 I dose correlated with the area ratio of bilateral lobes ( F =10.42,P =0.018 ) and ratio of bilateral gray scales in the normal thyroid function group ( F =10.66,P =0.017 ) ; whereas in the hypothyroidism group,the clinical outcome correlated with thyroid mass (F=7.65,P=0.013) and multifocal uptake pattern (F=8.01,P=0.011 ).Conclusions Computeraided normalization analysis is useful for 131I dose calculation in the treatment of hyperthyroidism.For patients with significantly unbalanced bilateral radiotracer distribution,increasing the dose and the number of treatments should be suggested.For patients with homogeneous radiotracer distribution,a linear method of dose increment according to the thyroid mass should be avoided to reduce the rate of hypothvroidism.