Virtual Touch Tissue Imaging on Acoustic Radiation Force Impulse Elastography

• DOI: 10.7863/ultra.33.4.585
• Publication Date: 2014-03-21T21:46:53Z
• Authors: Yi-Feng Zhang; Yong He; Hui-Xiong Xu; Xiao-Hong Xu; Chang Liu; Le-Hang Guo; Lin-Na Liu; Jun-Mei Xu
• Keywords: Adult; Male; Palpation; Adolescent; Reproducibility of Results; Middle Aged; Image Enhancement; Sensitivity and Specificity; 3. Good health; Diagnosis, Differential; User-Computer Interface; 03 medical and health sciences; 0302 clinical medicine; Hardness; Touch; Elastic Modulus; Image Interpretation, Computer-Assisted; Elasticity Imaging Techniques; Humans; Female; Thyroid Nodule; Algorithms; Aged

ObjectivesAcoustic radiation force impulse elastography is a newly developed ultrasound elasticity imaging technique that included both Virtual Touch tissue quantification and Virtual Touch tissue imaging (VTI; Siemens Medical Solutions, Mountain View, CA). This study aimed to evaluate the usefulness of VTI in differentiating malignant from benign thyroid nodules.MethodsThis study included 192 consecutive patients with thyroid nodules (n = 219) who underwent surgery for compressive symptoms or suspicion of malignancy. Tissue stiffness on VTI elastography was scored from 1 (soft) to 6 (hard). The VTI scores between malignant and benign thyroid nodules were compared. The intraobserver and interobserver agreement for VTI elastography was also assessed.ResultsOn VTI elastography: score 1 was found in 84 nodules (all benign); score 2 in 37 nodules (3 papillary carcinomas and 34 benign nodules); score 3 in 25 nodules (1 medullary carcinoma, 6 papillary carcinomas, and 18 benign nodules); score 4 in 53 nodules (50 papillary carcinomas and 3 benign nodules); score 5 in 17 nodules (14 papillary carcinomas and 3 benign nodules); and score 6 in 3 nodules (all papillary carcinomas). A VTI elasticity score of 4 or greater was highly predictive of malignancy (P< .01), and the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 87.0% (67 of 77), 95.8% (136 of 142), 91.8% (67 of 73), 93.1% (136 of 146), and 92.7% (203 of 219), respectively. The κ values were 0.69 for intraobserver agreement and 0.85 for interobserver agreement.ConclusionsVirtual Touch tissue elasticity imaging has great potential as an adjunctive tool combined with conventional sonography for differential diagnosis between benign and malignant thyroid nodules.