超声造影及弹性成像技术对超声造影无增强甲状腺结节良恶性的鉴别诊断价值

Value of contrast-enhanced ultrasonography and shear wave elastography in differential diagnosis of benign and malignant thyroid nodules without enhancement

目的探讨超声造影及实时剪切波弹性成像技术(SWE)对超声造影无增强甲状腺结节良恶性的鉴别诊断价值。方法选取2018年1月至2019年6月在解放军总医院行甲状腺结节超声造影检查,病灶呈无增强表现,且病灶均行SWE检查的患者100例,所有患者均经穿刺活检或手术取得病理结果,依据病理结果将患者分为良性组和恶性组。分析比较2组病灶的超声造影特征及弹性模量最大值(Emax)、弹性模量平均值(Emean),并应用四格表和ROC曲线分析超声造影及SWE对甲状腺结节良恶性的诊断效能。结果良性组与恶性组间无增强边界、结节整体完全无增强及Emax、Emean值差异均有统计学意义(P均<0.05),边界清晰主要见于良性组,边界不清主要见于恶性组,结节整体完全无增强则全部见于良性组,恶性组的Emax、Emean值均高于良性组。以病理结果为“金标准”,超声造影表现为无增强、边界不清诊断恶性甲状腺结节的敏感度、特异度、阴性预测值、阳性预测值分别为56%、75%、90%、30%;超声造影表现为整体完全无增强诊断良性甲状腺结节的敏感度、特异度、阴性预测值、阳性预测值分别为20%、100%、19%、100%。ROC曲线显示,Emax诊断恶性甲状腺结节的曲线下面积为0.696,以Emax>45.0 kPa为截断值时,其诊断敏感度和特异度分别为62.5%、64.3%;Emean诊断恶性甲状腺结节的曲线下面积为0.705,以Emean>47.7 kPa为截断值时,其诊断敏感度和特异度分别为56.3%、94.0%。结论甲状腺结节超声造影呈无增强时,是否边界清晰及是否整体完全无增强可用于鉴别结节良恶性;SWE对于超声造影无增强甲状腺结节良恶性的鉴别诊断具有一定的价值,二者结合应用可指导临床减少不必要的穿刺活检及手术治疗。

Objective To assess the value of contrast-enhanced ultrasound and real-time shear wave elastography(SWE)in the differential diagnosis of benign and malignant thyroid nodules without enhancement.Methods From January 2018 to June 2019,100 thyroid nodules were examined by contrastenhanced ultrasound in the General Hospital of the People's Liberation Army.The lesions showed no enhancement,and all lesions were examined by SWE.Pathological results were obtained by biopsy or surgery in all patients.According to the pathological results,the patients were divided into either a benign group or malignant group.The characteristics of contrast-enhanced ultrasound,maximum elastic modulus(Emax),and average elastic modulus(Emean)were compared between the two groups.The diagnostic efficacy of contrastenhanced ultrasound and SWE for benign and malignant thyroid nodules was analyzed using the four-fold table and ROC curve.Results The rates of no enhancement of the boundary and no enhancement of the whole nodule,as well as Emax and Emean values were significantly different between the two groups(P<0.05).Clear boundaries were mainly seen in the benign group,while unclear boundaries were mainly seen in the malignant group.The whole nodules without enhancement were all seen in the benign group.Emax and Emean values in the malignant group were higher than those in the benign group.The sensitivity,specificity,negative predictive value,and positive predictive value of unenhanced unclear boundaries for the differential diagnosis of benign and malignant thyroid nodules were 56%,75%,90%,and 30%,respectively;the corresponding values of whole nodules without enhancement were 20%,100%,19%,and 100%,respectively.The areas under the ROC curves of Emax and Emean were 0.696 and 0.705,respectively.When Emax>45.0 kPa was used as the cutoff value,the sensitivity and specificity for diagnosing malignant thyroid nodules were 62.5%and 64.3%,respectively.When Emean>47.7 kPa was used as the cutoff value,the sensitivity and specificity for diagnosing malignant thyroid nodules were 56.3% and 94.0%,respectively.Conclusion If there is no enhancement on contrast-enhanced ultrasound,whether the boundary is clear and whether there is enhancement in the whole nodule can be used to distinguish benign and malignant thyroid nodules.SWE has an appreciated value for the differential diagnosis of benign and malignant thyroid nodules without enhancement on contrast-enhanced ultrasound,which can help avoid unnecessary puncture biopsy and surgical treatment.