实时剪切波弹性成像鉴别甲状腺结节良恶性的应用价值

The value of shear wave elastography for differential diagnosis of benign and malignant thyroid nodules

目的探讨实时剪切波弹性成像（shearwavee｜astography，SWE）鉴别甲状腺结节良恶性的应用价值。方法分析156例患者156个结节的常规超声特征，包括位置、大小、形态、边界、回声强度、内部回声、后方回声、有无钙化及血供情况。测量结节杨氏模量值，包括最大值、平均值、最小值、标准差以及结节最硬处的平均值、最小值、标准差。绘制ROC曲线，获取各参数区分良恶性的临界值。与病理结果对照，比较常规超声和SWE鉴别甲状腺结节良恶性的效能。结果156个结节中包括良性38个，恶性118个。恶性结节杨氏模量值高于良性结节，差异有统计学意义（P≤0．001）。以杨氏模量平均值32．1kPa鉴别结节良恶性，敏感性、特异性分别为83．9％、92．1％，特异性高于常规超声，差异有统计学意义（P〈O．05），所有参数中，杨氏模量平均值ROC曲线下面积最大（0．880，95％CI：0．817，O．943），但差异无统计学意义（P〉0．05）。结论以结节的平均杨氏模量值鉴别甲状腺结节良恶性时，在不降低敏感性的前提下，能显著提高特异性。

Objective To investigate the value of shear wave elastography （SWE） for differential diagnosis of benign and malignant thyroid nodules. Methods A total of 156 patients referred for surgery of thyroid nodules underwent standard ultrasound as well as elastography. The following characteristics of all the nodules were assessed：location, size, shape, margin, eehogenicity, calcification and blood flow. The SWE elasticity indices of maximum （Emax）, mean （Emean）, minimum （Emin）, and standard deviation （Esd） were automatically calculated by the US system. Thresholds were calculated by receiver operating characteristic （ROC） curve analysis. The diagnostic performance of conventional US and SWE were compared. Histopathologic examination was used as the reference standard. Results Among a total of 156 nodules, 118 were malignant and 38 were benign. SWE elasticity indices were significantly higher in malignant than in benign nodules （ P ≤0.001） . Sensitivity and specificity for predicting malignancy were 83.9 %, 92.1 % respectively using Emean with a threshold of 32.1 kPa, the specificity was significantly higher than using conventional ultrasound （ P 〈0.05）. Area under the ROC curve （Az） of Emean was highest （0.880,95% CI..0.817,0.943）,however the differences were not significant（ P 〉0.05）. Conclusions SWE provides higher specificity for predicling malignancy without losing sensitivity.