超声弹性成像对甲状腺实性结节的鉴别诊断价值

Evaluation of the value of ultrasound elastography in differential diagnosis of benign and malignant thyroid solid nodules

目的探讨超声弹性成像弹性评分法及顺应性比值法在甲状腺实性结节鉴别诊断中的应用价值。方法对69例患者的86个甲状腺实性结节根据术后病理结果分为良性组及恶性组，分别对两组的超声弹性图像评分及顺应性比值进行回顾性分析，与术后病理结果对比，计算弹性评分法及顺应性比值法诊断的敏感性、特异性及准确性；绘制弹性评分法及顺应性比值法的受试者工作特征曲线（ROE曲线），选取最佳诊断界点。结果86个甲状腺结节中，良性组甲状腺结节共67个，结节直径（2．05±0．21）cm；恶性组甲状腺结节共19个，结节直径（1．62±0．12）em。良性组及恶性组结节直径比较，差异无统计学意义（t=-1．736，P〉0．05）。良性组与恶性组间弹性评分（中位数分别为2、3分）及顺应性比值（中位数分别为1．66、3．97）比较，差异有统计学意义（z值分别为-5．290、-5．450，P均〈0．05）。以弹性评分〉13分为鉴别甲状腺良、恶性的诊断界点，诊断敏感性、特异性及准确性分别为84．2％（16／19）、86．6％（58／67）和86．0％（74／86），ROC曲线下面积为0．854；以顺应性比值≥2．50为鉴别甲状腺良、恶性的诊断界点，诊断敏感性、特异性及准确性分别为89．4％（17／19）、86．6％（58／67）和87．2％（75／86），ROC曲线下面积为0．911。结论超声弹性成像弹性评分法及顺应性比值法均有助于甲状腺良、恶性结节的鉴别诊断，在临床具有较高的应用价值。

Objective To evaluate the value of ultrasound elastography score and strain ratio index in the differential diagnosis of thyroid solid nodules. Methods Eighty-six thyroid solid nodules of 69 patients were divided into 2 groups based on their pathologic results： benign nodules group and malignant nodules group. Compared with pathological results, each thyroid solid nodules＇ elastographic scores and strain ratio index were respectively analyzed. The sensitivity, specificity and accuracy of elasticity score and strain ratio index were calculated. The receiver operator characteristic （ROC） curves were draWn according to the results, to choose the best cut-off value. Results There were 67 nodules in benign nodules group and 19 nodules in malignant nodules group. The diameter of benign nodules was （2.05 ± 0.21）cm, malignant nodules was （1.62 ± 0.12）cm. There were no significant differences in the elasticity score and strain ratio index between benign and malignant nodules（t = - 1.736, P 〉 0.05）. Malignant lesions had a higher score and strain ratio index（median 3, 3.97, respectively） than benign ones（median 2, 1.66, respectively, Z = - 5.290, - 5.450, all P 〈 0.05）. If the cut-off value of the elastographic scores was equal or more than 3, the sensitivity, specificity and accuracy were 84.2% （16/19）, 86.6% （58/67） and 86.0% （74/86）, respectively, with an area under ROC curve of 0.854. If the cut-off value of the strain ratio index was equal or more than 2.50, the sensitivity, specificity and accuracy were 89.4% （17/19）, 86.6% （58/67） and 87.2% （75/86）, respectively, with an area under ROC curve of 0.911. Conclusion Elasticity score and strain ratio index are helpful in differentiating benign and malignant lesions of thyroid with high clinical value.