99Tcm-DTPA SPECT/CT眼眶显像评价甲状腺相关性眼病活动性:与临床活动性评分及MRI的对比分析

The activity of thyroid-associated ophthalmopathy assessed by 99Tcm-DTPA orbit SPECT/CT:comparison with clinical activity score and MRI

目的探讨99Tcm-二亚乙基三胺五乙酸(DTPA)SPECT/CT眼眶显像对甲状腺相关性眼病(TAO)活动性判断的价值。方法回顾性分析2016年2月至2017年1月临床诊断为TAO的33例患者[男性13例、女性20例,年龄(45.36±13.44)岁]的66个眼眶的99Tcm-DTPA SPECT/CT图像、临床活动性评分(CAS)及其中21例患者(42个眼眶)的MRI图像。用感兴趣区(ROI)技术进行半定量分析,计算眼眶与枕部区域的摄取比值(UR);用肉眼观察法分别判定SPECT/CT及MRI图像的每条眼外肌的活动性,并根据MRI处于活动期眼外肌的数量给每个眼眶进行CAS评分,≥3分判定为活动期,<3分为非活动期。活动期与非活动期TAO之间的UR比较采用t检验;UR与CAS评分、MRI评分之间的相关性采用Spearman相关性分析;SPECT/CT与MRI判断眼外肌活动性的一致性比较采用Kappa分析。绘制受试者工作特征(ROC)曲线,评价SPECT/CT诊断效能。结果①66个眼眶的CAS评分与UR呈中度相关(r=0.441,P=0.000);非活动期TAO的UR(1.20±0.58)低于活动期的UR(1.56±0.57),且差异有统计学意义(t=?2.476,P=0.016)。ROC曲线下面积为0.679,区分活动期与非活动期的UR阈值为1.20,灵敏度为79.5%,特异度为55.6%。②42个眼眶的MRI评分与UR呈显著相关(r=0.515,P=0.000),非活动期TAO的UR(1.00±0.60)低于活动期的UR(1.72±0.45),且差异有统计学意义(t=?4.438,P=0.000)。③99Tcm-DTPA SPECT/CT与MRI对42个眼眶共168条眼外肌的活动性判断呈中度一致性(kappa=0.569,P=0.000)。结论99Tcm-DTPA SPECT/CT眼眶显像是判断TAO活动性较为可靠及客观的影像学方法,值得在临床推广应用。

Objective To determine the value of 99Tcm-DTPA orbit SPECT/CT in evaluating the activity of thyroid-associated ophthalmopathy(TAO).Methods The 99Tcm-DTPA orbit SPECT/CT imaging data of 66 orbits of 33 patients[13 men and 20 women,age(45.36±13.44)years old]were retrospectively analyzed,along with the clinical activity score(CAS)and MRI of the 21 patients(42 orbits).The orbit/occipital area's uptake ratio(UR)was calculated by the ROI.The activity of each extraocular muscle(EOM)on the SPECT/CT and MRI images was assessed by visual analysis.MRI score of every orbit was obtained according to the number of active EOM,the range of which was 0-4.As for the CAS,≥3 represented the active stage,and the others denote the inactive stage.The UR between the active TAO and inactive TAO was compared using t test,the correlation between the UR and CAS/MRI score was calculated by Spearman analysis,and the consistency of the activity of every EOM assessed by SPECT/CT and MRI was evaluated by Kappa test.The receiver operating characteristic(ROC)curve was depicted to determine the diagnostic efficiency of SPECT/CT using CAS as the gold standard.Results①CAS was moderately correlated with the UR of all the 66 orbits(r=0.441,P=0.000).The UR of the inactive group(1.20±0.58)was significantly lower than that of the active group(1.56±0.57)(t=-2.476,P=0.016).The area under the curve of the ROC was 0.679.The threshold differentiating the inactive phase from the active one was 1.20,with the sensitivity of 79.5%and with the specificity being 55.6%.②The MRI score of the 42 orbits was significantly correlated with UR(r=0.515,P=0.000).The UR of the inactive group(1.00±0.60)was significantly lower than that of the active group(1.72±0.45)according to the MRI score(t=?4.438,P=0.000).③The activity of the 168 muscles assessed by 99Tcm-DTPA SPECT/CT was moderately consistent with that assessed by MRI(kappa=0.569,P=0.000).Conclusions 99Tcm-DTPA orbit SPECT/CT is a reliable and objective method to evaluate the activity of TAO,and it will be helpful in clinical practice.