Real-time Ultrasound Elastography in the Differential Diagnosis of Benign and Malignant Thyroid Nodules

Abstract

Abstract Background: Elastosonography is a promising noninvasive technique that developed in recent years for evaluating thyroid nodules. It assesses nodule stiffness or displacement depending on the applied force to differentiate malignant from benign thyroid nodules. Objectives: The aim of this study was to evaluate the diagnostic utility of real-time ultrasound (US) elastography in the differentiation the benign from malignant thyroid nodules. Patients and Methods: A prospective study was carried out on 40 patients attending the US unit/radiology in Al-Imamein Al-Kadhimein Medical City in Baghdad, Iraq, from September 2018 to August 2019. All patients were examined by B-mode US, color Doppler, and real-time elastography by Voluson-E6 US machine. Final diagnoses were obtained from histological and/or cytological evaluation. Results: The mean age of 40 patients was 43.7 ± 11.7 years, with a range of 25–70 years. Twenty-eight (70%) of them were female and 12 (30%) were male. Of the 40 lesions, 34 (85%) were benign and 6 (15%) were malignant lesions. Malignant thyroid nodules were significantly hypoechoic, with irregular margin, taller than wider, showed microcalcification, and exhibited a significant increase in vascularity with varying rates of sensitivity and specificity. Orientation (taller than wider) was the most US predictive pattern of malignancy with sensitivity, specificity, and accuracy of 66.7%, 100%, and 92.5%, respectively. The mean ± standard deviation of the strain ratio (SR) of all nodules was 2.7 ± 2.1 (range: 0.4–13.5) with significant result. The optimal SR cutoff value was >2.5 and showed to have a sensitivity of 100%, a specificity of 88.2%, a positive predictive value of 67%, a negative predictive value of 100%, and an accuracy rate of 90%. Conclusion: Elastosonography can assist in the differential diagnosis of malignant and benign thyroid nodules, as strain elastosonography improves the diagnostic performance in differentiating the benign and malignant thyroid nodules. SR is higher in malignant than benign nodules.