CT双期增强扫描对182枚甲状腺良恶性结节的诊断价值

Value of double-phase enhancement CT scan in the differential diagnosis of 182 benign and malignant thyroid nodules

目的探讨CT双期增强扫描在甲状腺良恶性结节鉴别诊断中的价值。方法回顾性分析经组织病理学证实的175例182枚甲状腺结节CT资料,其中良性结节60例,恶性结节122例。观察结节形态、密度、位置、ΔCT值(甲状腺与结节的CT差值)及强化方式在良恶性结节中的分布差异,采用单因素和多因素二分类Logistic回归分析进行检验,比较两组阳性CT征象对良恶性结节预测价值的OR值、预测概率曲线下面积。结果影像学显示形态(χ^(2)=50.661,P<0.001)、密度(χ^(2)=60.042,P<0.001)、位置(χ^(2)=48.916,P<0.001)、ΔCT值(χ^(2)=45.647,P<0.001)在甲状腺良恶性结节中的分布特征差异有统计学意义,强化方式在两组中差异无统计学意义(χ^(2)=1.586,P=0.434)。4种阳性征象联合预测概率曲线下面积值为0.899,当预测概率为0.711时,约登指数最大,此时诊断恶性结节的敏感度和特异性分别是0.869和0.783。结论 CT双期增强扫描对甲状腺良恶性结节鉴别诊断有重要价值,多种CT征象联合可提高甲状腺良恶性结节的预测价值。

Objective To evaluate the value of double-phase enhancement CT scan in the differential diagnosis of benign and malignant thyroid nodules. Methods The CT data of 182 nodules confirmed by histology in 175 patients were retrospectively analyzed, including 60 benign nodules and 122 malignant nodules. The shape, density, location, CT difference between thyroid and nodules(ΔCT) and reinforcement type were evaluated between the benign and malignant groups. Univariate and multivariate dichotomous Logistic regression were performed to evaluate the OR value of CT features of benign and malignant nodules, and the area under the receiver operating characteristic(ROC) curve were compared between the two groups. Results There were significant differences in the shape(χ^(2)=50.661, P<0.001), density(χ^(2)=60.042, P<0.001), location(χ^(2)=48.916, P<0.001) and ΔCT value(χ^(2)=45.647, P<0.001) between benign and malignant nodules, but there was no significant difference in reinforcement type(χ^(2)=1.586, P=0.434). The area under the ROC curve was 0.899 for the combined prediction probability of four positive signs. When the prediction probability was 0.711, the Youden Index reached its maximum value, and the sensitivity and specificity of diagnosing malignant nodules were 0.869 and 0.783, respectively. Conclusion CT double-phase enhanced scan is of great value in the differential diagnosis of benign and malignant thyroid nodules. Combination of multiple CT signs can improve the accuracy of diagnosis.