Value of contrast enhanced ultrasound combined with elastography in differential diagnosis of thyroid imaging reporting and data system 4 thyroid nodules

Abstract

Objective To assess the diagnostic value of contrast enhanced ultrasound (CEUS), elastography and their combined use in diagnosing thyroid nodules of thyroid imaging reporting and data system (TI-RADS) 4. Methods From November 2011 to August 2016, 159 TI-RADS 4 nodules diagnosed by conventional ultrasound were prospectively enrolled and examined by CEUS and elastography before surgery. Multivariate logistic regression models were established for CEUS and CEUS combined with elastography to diagnose thyroid malignancy. The diagnostic performances of CEUS, elastography and their combined use were evaluated with the receiver operating characteristic (ROC) curve. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and omission diagnostic rate of CEUS, elastography and their combined use were compared by Chi-square test. Results The CEUS features significantly predicting malignancy were heterogeneous enhancement, hypoenhancement, without or incomplete ring-enhancement and later time to peak than the surrounding parenchyma (χ2=24.378, 69.194, 29.434 and 7.375, all P 0.05). Conclusion The diagnostic value of CEUS combined with elastography was remarkably significant in the differential diagnosis of TI-RADS 4 nodules. Key words: Ultrasonography; Elasticity imaging techniques; Thyroid nodule