声辐射力脉冲弹性成像在甲状腺单发实性结节良恶性鉴别诊断中的应用价值

摘要

目的探讨声辐射力脉冲弹性成像（ARFI）技术判断甲状腺单发实性结节良恶性的价值。方法选取2011年4月至2012年2月上海市第十人民医院经常规超声检查发现甲状腺单发实性或以实性为主（囊性＜25％）结节的42例患者，共42个结节。对42例患者42个结节行常规超声检查，采用声触诊组织定量（VTQ）技术检测病灶组织剪切波速度（SWV），采用声触诊组织成像（VTI）技术对病灶组织进行VTI弹性分级。常规超声以符合3项及以上恶性结节超声表现、VTQ以SWV值≥2．87 m／s、VTI以VTI分级≥Ⅳ级、常规超声＋VTI／VTQ以常规超声或VTI／VTQ其中之一诊断为恶性作为恶性结节诊断标准。以病理学诊断结果作为金标准，计算常规超声、VTQ、VTI及常规超声＋VTI／VTQ诊断甲状腺恶性单发实性结节的敏感度、特异度、阳性预测值、阴性预测值。结果42个甲状腺结节经手术后病理证实良性结节30个（结节性甲状腺肿16个，腺瘤性甲状腺肿13个，亚急性甲状腺炎1个），恶性结节12个（均为乳头状癌）。常规超声检查有3项及以上恶性结节超声表现的结节14个，包括良性结节4个，恶性结节10个；少于3项恶性结节超声表现的结节28个，包括良性结节26个，恶性结节2个。常规超声诊断甲状腺恶性单发实性结节的敏感度、特异度、阳性预测值、阴性预测值分别为83．3％（10／12）、86．7％（26／30）、71．4％（10／14）、92．9％（26／28）。 SWV值≥2．87 m／s的结节15个，包括良性结节5个，恶性结节10个；SWV值＜2．87 m／s的结节27个，包括良性结节25个，恶性结节2个；VTQ诊断甲状腺恶性单发实性结节的敏感度、特异度、阳性预测值、阴性预测值分别为83．3％（10／12）、83．3％（25／30）、66．7％（10／15）、92．6％（25／27）。 VTI分级≥Ⅳ级的结节19个，包括良性结节8个，恶性结节11个；VTI分级＜Ⅳ级的结节23个，包括良性结节22个，恶性结节1个；VTI诊断甲状腺恶性单发实性结节的敏感度、特异度、阳性预测值、阴性预测值分别为91．7％（11／12）、73．3％（22／30）、57．8％（11／19）、95．7％（22／23）。常规超声＋VTI诊断甲状腺恶性单发实性结节的敏感度、特异度、阳性预测值、阴性预测值分别为91．7％（11／12）、80．0％（24／30）、64．7％（11／17）、96．0％（24／25）。而常规超声＋VTQ诊断甲状腺恶性单发实性结节的敏感度、特异度、阳性预测值、阴性预测值分别为91．7％（11／12）、83．3％（25／30）、68．8％（11／16）、96．2％（25／26）。结论单独的ARFI技术诊断甲状腺单发实性结节良恶性的能力并不优于常规超声，但是两者联合应用可提高甲状腺单发实性结节良恶性鉴别诊断水平。%Objective To explore the value of virtual touch tissue imaging (VTI) and virtual touch tissue quantification ( VTQ) of acoustic radiation force impulse ( ARFI) elastography in the differential diagnosis between benign and malignant solitary solid thyroid nodules in ultrasound .Methods The ARFI elastography characteristics and ultrasound (US) features of 42 histologically proven solid or predominantly solid thyroid nodules in 42 patients with a solitary nodule were reviewed .The pathological diagnosis was the gold standard and the sensitivity ,specificity,positive predictive value (PPV) and negative predictive value (NPV) of US, VTQ and VTI in diagnosis of malignant solitary solid thyroid nodules were caculated. Results Forty-two nodules included 30 benign lesions(16 nodular goiters,13 adenomatous goiters and one subacute thyroiditis)and 12 malignant lesions(papillary carcinomas).The sonographic features that suggested malignancy include hypoechogenicity , irregular or microlobulated margin, microcalcification, intranodular bloodflow and taller than wide shape .Forteen nodules(four benign nodules and ten malignant nodules ) had three or more of these features and 28 nodules(26 benign nodules and two malignant nodules ) had less than three of these features.The sensitivity,specificity,PPV and NPV of US was 83.3%(10/12),86.7%(26/30), 71.4%(10/14) and 92.9%(26/28).The shear wave velocities(SWV) of 15 nodules(five benign nodules and ten malignant nodules ) were greater than or equal to 2.87 m/s and those of 27 nodules (25 benign nodules and two malignant nodules ) were less than 2.87 m/s.The sensitivity,specificity,PPV and NPV of VTQ was 83.3%(10/12),83.3%(25/30),66.7%(10/15) and 92.6%(25/27),respectively.The VTI scores of 19 nodules(eight benign nodules and 11 malignant nodules) were greater than or equal to Ⅳand those of 23 nodules (22 benign nodules and one malignant nodule ) were less than Ⅳ.The sensitivity, specificity,PPV and NPV of VTI was 91.7%(11/12),73.3%(22/30),57.8%(11/19) and 95.7%(22/23),respectively.The sensitivity,specificity,PPV and NPV of US combining VTI was 91.7%(11/12), 80.0%(24/30),64.7%(11/17) and 96.0%(24/25),respectively.The sensitivity,specificity,PPV and NPV of US combining VTQ was 91.7%(11/12),83.3%(25/30),68.8%(11/16) and 96.2%(25/26), respectively.Conclusion ARFI alone is not superior to US in predicting malignancy in thyroid nodules but can be used as a supplementary tool to improve the diagnostic level .