Ultrasound elastography in the diagnostic evaluation of indeterminate thyroid nodule

Abstract

Objective: To assess the accuracy of US-elastography in the evaluation of indeterminate thyroid nodules, using the cytological/histopathological analysis as the reference. Patients and methods: Fifty patients with 73 indeterminate thyroid nodules were enrolled in this prospective study. They were examined using US features and elastography scoring according to Rago criteria; then, fine-needle or postoperative biopsy was taken and diagnosis was made. Results: Fifty patients with 73 indeterminate thyroid nodules were included, 16 nodules were malignant and 57 were benign. On US elastography, all 57 nodules diagnosed as benign had a score of 1–3, while 15 of 16 (93.75%) diagnosed as carcinoma had a score of 4–5, with 93.3% sensitivity, 100% specificity and 97.8% accuracy. Combined US findings with elastography revealed that hypoechogenicity/score 4–5 was most predictive of malignancy with sensitivity 80%, specificity 100%; and accuracy 93.4%. The strain ratio cutoff value for malignant nodules was determined as 2.3. Five nodules out of sixteen had SR between 2.31 and 4 (sensitivity 96% and specificity 83%). Conclusion: Thyroid nodules with suspicious US criteria can be evaluated by US elastography that seems to be a useful addition for the assessment of such indeterminate nodules. It may reduce FNAC or select a nodule for aspiration.

Keywords

• Elastography
• Ultrasound
• Thyroid gland
• Indeterminate
• Thyroid nodules