目的：探讨超声造影（CEUS）结合定量分析法在诊断甲状腺微小乳头状癌（PTMC）中的价值。方法：回顾性分析63个甲状腺实性结节（直径≤10 mm）的超声造影增强特征，应用QLAB软件定量分析结节峰值强度（PI）、上升时间（RT）、平均通过时间（MTT）、曲线下面积（AUC）、浓度减半时间（TPH）、达峰时间（TTP）、上升斜率（WS）各定量参数，所有结节性质均经手术病理证实。结果：PTMC与甲状腺良性小结节的增强方式有差别（χ2=33.542，P=0.000），以早期低增强或低增强判断PTMC的敏感性、特异性分别为82.82%、79.40%。PTMC中PI低于其周围组织、甲状腺良性小结节及其周围组织，且差异有统计学意义（P<0.05）。甲状腺良性小结节PI低于其周围组织，且差异有统计学意义（P<0.05）。PTMC中AUC、TTP、WS均低于甲状腺良性小结节周围组织，且差异有统计学意义（P<0.05）。其余各组数据比较差异均无统计学意义（P>0.05）。甲状腺定量分析参数PI诊断PTMC的敏感性、特异性分别为86.21%、88.23%。结论：PTMC以早期低增强或低增强为主要灌注模式。定量参数中以PI价值最大，可作为鉴别甲状腺良、恶性小结节的重要参考指标。甲状腺定量参数RT、MTT、AUC、TPH、TTP、WS对鉴别甲状腺良、恶性小结节价值不大。

Objective: To explore the value of CEUS combined with quantitative analysis in the diagnosis of papillary thyroid microcarcinoma(PTMC). Methods: The CEUS features of 63 solid thyroid nodules(diameter≤10 mm) were retrospectively analyzed. The peak intensity(PI), the rise time(RT), the mean transit time(MTT), the area under the curve(AUC), the time from peak to one half(TPH), the time to peak(TTP), the wash in slope(WS) of nodules were quantitatively analyzed by QLAB software, all nodules were confirmed by surgery and pathology. Results: There was a difference between PTMC and benign small thyroid nodules in enhancement patterns(χ2=33.542, P=0.000). The sensitivity and specificity of early hypo-enhancement or hypo-enhancemen in the diagnosis of PTMC were 82.82% and 79.40% respectively. PI in PTMC was lower than that in tissues surrounding thyroid malignant nodules, benign small nodules of thyroid and tissues surrounding benign small nodules, and the difference was statistically significant(P<0.05). The PI of thyroid benign nodules was lower than that of tissues surrounding the benign nodules, and the difference was statistically significant(P<0.05). The AUC, TTP and WS of PTMC were lower than those of tissues surrounding the benign nodules(P<0.05). There was no significant difference in other groups(P>0.05). The sensitivity and specificity of PI in the diagnosis of PTMC were 86.21% and 88.23% respectively. Conclusion: The main perfusion mode of PTMC was early hypo- or hypo-enhancement. PI is the most valuable quantitative parameter of ROI, which can be used as an important reference index for differentiating benign and malignant thyroid nodules. Quantitative parameters such as RT, MTT, AUC, TPH, TTP and WS have little value in differentiating benign and malignant thyroid nodules.