Qualitative Evaluation of Virtual Touch Imaging Quantification: A Simple and Useful Method in the Diagnosis of Breast Lesions

Objective: To test the value of qualitative virtual touch imaging quantification (VTIQ) features in differentiating benign from malignant breast lesions. Methods: From November 2016 to August 2017, 230 lesions were subjected to conventional US and virtual touch imaging quantification before biopsy. The maximum shear wave velocity (SWVmax) was measured using a standardized method. Qualitative VTIQ features, including the "stiff rim" sign and color pattern classification, were assessed according to a binary classification. The sensitivity, specificity and area under the receiver operating curve (AUC) of Breast Imaging Reporting and Data System (BI-RADS), SWVmax, qualitative VTIQ features, and combined data were compared. Results: Among the 230 breast lesions, 150 were benign and 80 were malignant. Compared to the benign lesions, the malignant ones had higher SWVmax values and were more likely to show the "stiff rim" sign and VTIQ pattern 2 (P <0.001 for all). The AUC value was 0.885 for the qualitative VTIQ combination (the presence of the "stiff rim" sign and/or the display of VTIQ pattern 2), similar to that for SWVmax (P=0.472). BI-RADS combined with the qualitative VTIQ combination and with SWVmax yielded similar results, including significantly higher AUC values (P = 0.018 and 0.014, respectively), significantly higher specificities (P<0.001 for both), and nonsignificantly decreased sensitivities (P = 0.249 for both) compared to BI-RADS alone. Conclusion: The dual-category classification of qualitative VTIQ features according to the presence of the "stiff rim" sign and/or the classification of VTIQ pattern 2 is a simple and useful method that may be representative of quantitative VTIQ parameters in the evaluation of breast masses.