Preoperative differentiation of thyroid adenomas and thyroid carcinomas using high resolution contrast-enhanced ultrasound (CEUS)

Background: To evaluate the impact of high-resolution contrast-enhanced ultrasound (CEUS) in combination with Color Coded and Power Doppler Sonography (CCDS/PD) in the preoperative differentiation of thyroid adenomas and thyroid carcinomas. Methods: A total of 101 patients (55 female, median age 54 years) underwent surgery for thyroid adenoma and thyroid carcinoma. CCDS/PD and CEUS were performed in all patients by an experienced examiner using a multifrequency linear transducer (6-9 or 6-15 MHz) and were digitally stored. Reading of the ultrasound images was performed by two experienced radiologists in consensus. A histopathological evaluation was obtained as standard of reference in all patients. Results: Altogether, 75 thyroid adenomas and 26 thyroid carcinomas were detected. Mean diameter of thyroid adenomas and thyroid carcinomas was 27mm and 32 mm, respectively. The differences in microcirculation of thyroid adenomas and thyroid carcinomas were statistically highly significant (p < 0.01). Representative features for thyroid adenomas were either no wash-out or wash-out with persisting edge in late phase, for thyroid carcinomas a complete wash-out in late phase. Thus, a calculation of sensitivity, specificity, positive and negative predictive value of 81%, 92%, 97% and 63%, respectively, for the differentiation of benignity and malignancy was possible. Conclusions: Dynamic evaluation of microcirculation using CEUS and CCDS/PD enables a more reliable preoperative discrimination between thyroid adenomas and thyroid carcinomas.