99mTC-二乙烯三胺五乙酸眼眶SPECT/CT在甲状腺相关性眼病分型及活动度评价中的作用

目的 探讨根据^99mTC-二乙烯三胺五乙酸(diethylenetriaminepentaacetic acid,DTPA)眼眶单光子发射计算机断层扫描(single photon emission computed tomography,SPECT)/计算机断层扫描(computed tomography,CT)图像分析进行甲状腺相关性眼病(thyroid associated ophthalmopathy,TAO)分型,并通过计算其显像剂摄取比值(uptake rate,UR)评价在TAO活动度评估中的作用。方法 分析205例TAO患者,根据^99mTC-DTPA 眼眶SPECT/CT图像分析结果将TAO患者分为两种类型:Ⅰ型以球后病变为主,Ⅱ型以眶周病变为主,进行临床指标比较,并分析与临床活动性评分(clinical activity scores,CAS)的相关性。结果 Ⅰ型TAO球后部位显像剂摄取比值(uptake rate of retrobulbar region,URR)明显高于Ⅱ型TAO患者,而Ⅱ型TAO眶周部位显像剂摄取比值(uptake rate of periorbital region,URP)明显高于Ⅰ型,差异具有统计学意义(P<0.001);Ⅰ型和Ⅱ型TAO在性别(P=0.001)、年龄(P<0.001)、CAS评分(P<0.001)、复视评分(P<0.001)、促甲状腺激素受体抗体(thyrotropin receptor antibody,TRAb)(P=0.004)等方面差异均有统计学意义;Ⅱ型TAO患者中,UR值与CAS呈正相关(r=0.407,P<0.001),受试者操作特征曲线(receiver operating characteristic curve,ROC)显示,Ⅱ型TAO中当UR≥1.596判断疾病处于活动期的灵敏度为68.4%,特异度为64.3%,临床应用价值有限。TRAb与CAS呈正相关(r=0.215,P=0.007),但相关性较弱。结论 ^99mTC-DTPA 眼眶SPECT/CT可以为甲状腺相关性眼病患者分型提供客观依据,但用于活动度评价效果不理想。

Role of 99mTC-diethylenetriaminepentaacetic acid orbital SPECT/CT in subtype analysis and activity evaluation of thyroid associated ophthalmopathy

Objective To investigate the classification of thyroid associated ophthalmopathy(TAO)subtypes by single photon emission computed tomography(SPECT)/computed tomography(CT) image analysis of ^99mTC-diethylenetriaminepentaacetic acid (DTPA), and to evaluate its role in activity assessment of TAO by calculating imaging agent uptake rate(UR).Methods An analysis was conducted on 205 patients who were diagnosed with TAO.According to ^99mTC-DTPA orbital SPECT/CT image analysis, TAO patients were divided into two types: type I was mainly retrobulbar lesions, type Ⅱ was mainly periorbital lesions. The clinical indexes were compared and the relationship between the uptake rate of imaging agents and clinical activity scores (CAS) were analyzed. Results The uptake rate of retrobulbar region (URR) of type Ⅰ TAO was significantly higher than that of type Ⅱ TAO, while the uptake rate of periorbital region (URP) of type Ⅱ TAO was higher. The difference was statistically significant (P<0.001). Type I and Ⅱ had significant differences in gender(P=0.001),age (P<0.001), CAS (P<0.001), diplopia scores (P<0.001)and thyrotropin receptor antibody(TRAb)(P=0.004). In type Ⅱ TAO, UR was correlated with the CAS(r=0.407,P<0.001).Receiver operating characteristic curve(ROC) curve analysis showed that the sensitivity of the type1 Ⅱ TAO when UR≥1.596 to judge the disease was active, the sensitivity is 68.4%, the specificity is 64.3%,and the clinical application value was limited. TRAb was correlated with CAS (r =0.215,P=0.007), but the correlation was weak.Conclusion ^99mTC-DTPA orbital SPECT/CT can provide an objective basis for the classification of patients with TAO, but it is not ideal for the evaluation of activity.