Shear wave elastography versus real-time elastography on evaluation thyroid nodules: a preliminary study

To comparatively evaluate shear wave elastography (SWE) and real-time elastography (RTE) in distinguishing malignant from benign thyroid nodules.

49 patients with 64 focal thyroid nodules were enrolled and underwent SWE and RTE before surgery. SWE elasticity indices (mean, minimum and maximum value of 2-mm region of interest) of nodules were measured. For RTE, elastograms were assessed by Rago criteria and nodules with scores of 4 or 5 were classified as suspicious for malignancy. Surgery histopathologic results were adopted as diagnostic standard.

Of the 64 nodules, 19 were papillary thyroid carcinomas and 45 were benign. SWE indices were significantly higher in malignant than benign nodules (P<0.05). Areas under the ROC curves (AUC) of SWE parameters were 0.840, 0.831 and 0.788, which were not significantly different from that of RTE showed as 0.880 (P=0.148-0.482). When the most accurate cut-off, 38.3kPa for mean value was applied to predict malignancy, the diagnostic specificity, sensitivity, accuracy, positive predictive value and negative predictive value of SWE and RTE were 68.4% versus 79.0%, 86.7% versus 84.4%, 81.3% versus 78.1%, 68.4% versus 64.7% and 86.7% versus 83.3%, respectively (P=0.683-1.000).

SWE as a promising tool can be performed in differentiating thyroid nodules with comparable results to RTE.