探讨常规超声（US）与超声造影（CEUS）在甲状腺微小乳头状癌（PTMC）的诊断价值。

收集2013年2月至2017年5月南京市浦口医院、南京大学医学院附属鼓楼医院及南京军区南京总医院甲状腺结节患者158例，手术切除的结节最大直径<1 cm，其中74例甲状腺小乳头状癌（PTMC组），84例腺瘤（TA组）。术前均行US和CEUS检查，对PTMC组和TA组的边缘、纵横比和增强方式、均匀性和强度等变量先进行χ²检验或Mann-Whitney U检验，再采用Logistic回归分析筛选甲状腺微小癌的危险因素。

TA组和PTMC组在边缘、纵横比、钙化、包膜连续4项US检查参数方面比较，差异均有统计学意义（P均<0.01），CEUS的强化方式、强度和均匀性定性分析以及Peak、Grad、Area定量分析显示，差异均有统计学意义（P均<0.01）。US诊断甲状腺癌的敏感度、特异度和准确性分别为82.1%（69/84）、66.2%（49/74）、74.7%（118/158）。Logistic回归分析显示纵横比≥1、包膜不连续和低强化是影响PTMC超声征象的危险因素（P<0.05）。以Logistic回归模型判断甲状腺恶性结节概率的预测值绘制受试者工作特征（ROC）曲线，曲线下面积为0.887，敏感度、特异度分别为81.7%和84.2%。

US联合CEUS对小于1 cm的甲状腺肿瘤的鉴别诊断具有重要价值。

To evaluate the combination of conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) in the differential diagnosis of papillary thyroid microcarcinoma (PTMC) and thyroid adenoma (TA).

From February 2013 to May 2017, 158 patients with single thyroid lesions (74 PTMC, 84 TA) in Drum Tower Hospital, Medical School of Nanjing University and Nanjing General Hospital were enrolled in this retrospective study. Before operation, all the patients were examined by conventional US and CEUS. The ultrasonic data and pathologic findings were available. The margin, microcalcification, the degree and homogeneity of enhancement of the TA and PTMC, and other variables were subjected to Fisher′s exact test or Mann-Whitney U analysis. The risk factors of thyroid microcarcinoma were screened by logistic regression analysis.

There were statistically significant differences in edge, aspect ratio, calcification and four consecutive US examination parameters in group TA and group PTMC (P<0.01). Qualitative analysis of CEUS intensification, intensity and uniformity, and quantitative analysis of Peak, Grad and Area showed that the differences were statistically significant (all P<0.01). The sensitivity, specificity and accuracy of US in diagnosing thyroid cancer were 82.1% (69/84), 66.2% (49/74) and 74.7% (118/158), respectively. Multivariate logistic regression analysis indicated that the risk factors of PTMC in ultrasonography were A/T ratio≥1, invasion and low enhancement (P<0.05). The receiver operating characteristic curve (ROC) of predictive value of Logistic regression model to determine the probability of thyroid malignant nodules was drawn, and the area under the curve was 0.887, and the sensitivity and specificity were 81.7% and 84.2% respectively.

Conventional US combined with CEUS is of great value in the differential diagnosis of thyroid tumors less than 1cm.