Study on the diagnostic values of virtual touch tissue imaging quantification and virtual touch tissue quantification techniques in differentiating thyroid benign and malignant nodules / 中华医学超声杂志（电子版）

ABSTRACT

Objective To compare the diagnostic performances of two elastography techniques, virtual touch tissue imaging quantification (VTIQ) and virtual touch tissue quantification (VTQ), in differentiating between benign and malignant thyroid nodules. Methods A total of 182 patients with 186 nodules evaluated by VTQ and VTIQ were enrolled in this study. Shear wave velocities (SWV) of benign and malignant nodules were measured and compared between different groups by t test . The receiver operating characteristic curve (ROC) was used to assess the value of VTIQ and VTQ in differentiating benign and malignant nodules. And the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of VTIQ and VTQ were calculated. According to areas under the curve (AUC), the diagnostic values of these two elastography techniques for thyroid nodules′ qualitative diagnosis were compared by Z test. Results In pathology, 104 thyroid nodules were benign and 82 were malignant. AUC of VTIQ SWV mean, VTIQ SWV median, VTQ SWV mean, VTQ SWV median were 0.848, 0.790, 0.759, 0.717, respectively. In the VTIQ and VTQ techniques, the SWV mean had higher diagnostic efficacy than the SWV median (VTIQ techniques Z=2.104, P=0.0354; VTQ techniques Z=2.190, P=0.0285). There were statistical differences in the diagnosis performance between VTIQ SWV mean and VTQ SWV mean (Z =2.115, P=0.0344). The VTIQ SWV mean value in the nodule had the best diagnostic value in comparison with other SWV values. The cut-off value of VTIQ SWV mean was 2.91 m/s. According to ROC curve analysis, the sensitivity, specificity, accuracy, PPV and NPV for VTIQ SWV mean were 72.12%, 87.80%, 79.03%, 88.24%, 71.29%, respectively. Conclusions The results demonstrated that VTQ and VTIQ have good diagnostic performance on distinguishing malignant from benign thyroid nodules. VTIQ SWV mean shows a better diagnostic performance than VTQ SWV mean.