SE及SWE技术对≤1 cm的TI-RADS 4类甲状腺结节的鉴别诊断价值

Value of SE and SWE elastic ultrasound in differential diagnosis of TI-RADS 4 thyroid nodule with a maximum diameter≤1 cm

目的:探索应变弹性成像(strain elastography,SE)与剪切波弹性成像(shear-wave elastography,SWE)对最大径≤1 cm的甲状腺影像报告和数据系统(Thyroid Imaging Reporting and Data System,TI-RADS)4类甲状腺结节的鉴别诊断价值。方法:回顾并分析251例患者的263个甲状腺结节的超声检查结果,患者术前均行常规超声、SE及SWE检查,以手术后病理学检查或细针穿刺活检结果为金标准。在SE图像上,以结节周围同深度的甲状腺组织为参照,测量弹性应变率比值(strain ratio,SR);在SWE图像上同理测量剪切波速度比(E_(ratio))。通过受试者工作特征(receiver operating characteristic,ROC)曲线得到SR及E_(ratio)诊断截断值,评估不同检查方法的诊断效能。结果:研究共纳入恶性病灶144个,良性病灶119个。恶性组的SR和E_(ratio)值分别高于良性组(SR:3.14 vs 1.20;E_(ratio):2.13 vs 1.21;P<0.05)。SR、E_(ratio)及常规超声检查的ROC曲线的曲线下面积分别为0.896、0.840及0.746(P<0.05)。以SR≥2.32对最大径≤1 cm的TI-RADS 4类恶性结节的灵敏度、特异度及诊断准确度分别为87.5%、88.2%及87.8%;联合常规超声及SR将诊断特异度提升至90.8%;常规超声与SR及E_(ratio)联合将诊断特异度提升至97.8%。结论:对于最大径≤1 cm TI-RADS 4类甲状腺结节,相较于E_(ratio)指标,SR指标对良恶性鉴别诊断具有较高效能,SR与常规超声联用,或进一步与SWE中E_(ratio)联用,可以提高诊断特异度,避免良性结节患者接受侵入性操作可能性。

Objective:To explore the value of strain elastography(SE)and shear wave elastography(SWE)in the differential diagnosis of Thyroid Imaging Reporting and Data System(TI-RADS)4 thyroid nodules with a maximum diameter≤1 cm.Methods:The ultrasonic imaging results of 263 thyroid nodules in 251 patients who underwent conventional ultrasound,SE and SWE before surgery were retrospectively analyzed,and the pathological results of surgical resection or fine-needle aspiration biopsy were the gold standard.On the SE image,the thyroid tissue around the nodule at the same depth was used as a reference to measure the strain ratio(SR);on the SWE image,the E_(ratio)was similarly measured.The diagnostic cutoff values of SR and E_(ratio)were obtained by receiver operating characteristic(ROC)curve to evaluate the diagnostic efficacy of different examination methods.Results:A total of 144 malignant lesions and 119 benign lesions were included in the study.The SR and E_(ratio)values of the malignant group were higher than those of the benign group(SR:3.14 vs 1.20;E_(ratio):2.13 vs 1.21;P<0.05).The areas under the ROC curves of SR,E_(ratio)and ultrasound were 0.896,0.840 and 0.746,respectively(P<0.05).The sensitivity,specificity and diagnostic accuracy of SR≥2.32 in the diagnosis of TI-RADS 4 malignant nodules with a maximum diameter≤1 cm were 87.5%,88.2%and 87.8%,respectively;combined with ultrasound and SR,the diagnostic specificity was increased to 90.8%;ultrasound combined with SR and E_(ratio)improved the diagnostic specificity to 97.8%.Conclusion:For TI-RADS 4 thyroid nodules with a maximum diameter≤1 cm,compared with the E_(ratio)index,the SR index has higher efficacy in the differential diagnosis of benign and malignant.The combination of SR with conventional ultrasound,or further combined with E_(ratio)in SWE,can improve the diagnostic specificity and avoid the possibility of invasive procedures in patients with benign nodules.