实时剪切波弹性成像对甲状腺结节良恶性的诊断及影响因素分析

目的 探讨剪切波弹性成像(SWE)各参数对甲状腺结节良恶性鉴别诊断的临床价值。方法 应用SWE对拟接受手术或活检的221例甲状腺结节患者(265个结节)进行检查,测量结节的绝对弹性值。以病理结果为金标准,绘制ROC曲线,得到最优的诊断界点,并以此进行良恶性诊断。根据ROC曲线下面积评价各个SWE参数的诊断价值。同时,分析可能存在的影响因素。结果 265个甲状腺结节中,良性177个,恶性88个。恶性结节的杨氏模量均高于良性结节,差异有统计学意义(P均<0.05)。5个SWE参数(SWE_whole_mean、SWE_whole_min、SWE_mean、SWE_min、SWE_max)诊断结节良恶性的ROC曲线下面积分别为0.793、0.656、0.801、0.796和0.791。SWE_mean的ROC曲线下面积(AUC)面积最大,以最优的诊断界点为39.2 kPa进行良恶性诊断,诊断的敏感度和特异度分别为67.05% 和83.62%。各可能的影响因素中,结节内钙化会使测量到的杨氏模量值增加。SWE与常规超声联合应用的诊断敏感度为86.36%。结论 SWE有助于甲状腺结节良恶性的鉴别诊断。

Real-time shear wave elastography in differentiating malignant from benign thyroid nodules and its influence factors

Objective To evaluate diagnostic performance of shear wave elastography (SWE) on distinguishing malignant from benign thyroid nodules. Methods A total of 221 patients with 265 focal thyroid nodules scheduled thyroid surgery or thyroid biopsy were performed SWE examination. SWE_whole_mean, SWE_whole_min, SWE_mean, SWE_min, and SWE_max values were measured. SWE parameters were correlated with cytology or histology and their optimal cut-off values were calculated using receiver operating characteristic (ROC) curve. Area of ROC curve (AUC) was used to assess and compare the diagnostic performance in discriminating thyroid nodules. Moreover, the possible influence factors were evaluated. Results There were 177 benign nodules and 88 malignant nodules on cytology or histology in the total of 265 thyroid nodules. All the SWE parameters were higher in malignancy than benign nodules (all P<0.05). The AUC of 5 SWE parameters (SWE_whole_mean, SWE_whole_min, SWE_mean, SWE_min and SWE_max) was 0.793, 0.656, 0.801, 0.796 and 0.791, respectively. The area under ROC curve of SWE_mean was the largest. And the optimal cut-off value of SWE_mean as 39.2 kPa achieved a sensitivity of 67.05% and a specificity of 83.62%. Among the possible influence factors, calcifications increased the Young modulus. When conventional US was combined with SWE, the sensitivity was raised to 86.36%. Conclusion SWE is helpful for the identification of benign and malignant thyroid nodules.