Preliminary Evaluation of Virtual Touch Tissue Imaging Quantification for Differential Diagnosis of Metastatic and Nonmetastatic Cervical Lymph Nodes.

Abstract

Virtual Touch tissue imaging quantification (VTIQ; Siemens Medical Solutions, Mountain View, CA) is useful for assessing tissue hardness. This study aimed to investigate the value of VTIQ in differential diagnosis of cervical lymph nodes. We retrospectively analyzed conventional sonograms and VTIQ images of 85 pathologically confirmed patients with superficial lymph node lesions. Conventional sonography was first performed, with 2-dimensional images described. Then VTIQ shear wave velocity (SWV) values of superficial lymph nodes were measured. With pathologic diagnosis as the reference standard, a receiver operating characteristic curve was generated to evaluate VTIQ efficacy in differential diagnosis of metastatic and nonmetastatic cervical lymph nodes. Of the 85 nodes, 44 and 41 were metastatic and nonmetastatic, respectively. The latter group included 24 and 17 hematologic/lymphatic system disease and reactive hyperplastic nodes, respectively. Shear wave velocity values of metastatic nodes were significantly higher than those of their nonmetastatic counterparts (P < .001). With an area under the curve (AUC) of 0.953 and SWV cutoff of 3.27 m/s, accuracy, sensitivity, and specificity were 89.4%, 88.6%, and 90.2%, respectively, for distinguishing metastatic and nonmetastatic nodes. An AUC of 0.943 and SWV cutoff of 3.23 m/s yielded accuracy, sensitivity, and specificity of 88.2%, 88.6%, and 87.5% for differentiating metastatic from hematologic/lymphatic system disease nodes. Finally, an AUC of 0.968 and SWV cutoff of 3.27 m/s yielded accuracy, sensitivity, and specificity of 90.2%, 88.6%, and 94.1% for differentiating metastatic from reactive hyperplastic nodes. Virtual Touch tissue imaging quantification is efficient in differential diagnosis of metastatic and nonmetastatic cervical lymph nodes.