Comparison of 2D ultrasound-based composite score method and contrast enhanced ultrasound in differential diagnosis of thyroid micronodules / 中华医学超声杂志（电子版）

ABSTRACT

Objective To evaluate the diagnostic value of 2D ultrasound (2DUS)-based composite score method and contrast enhanced ultrasound (CEUS) in differentiation between thyroid microcarcinomas and benign micronodules. Methods A total of 216 consecutive patients with 258 thyroid micronodules underwent 2DUS and CEUS examinations before thyroidectomy from June 2011 to October 2013. The scoring of each nodule was based on five 2DUS features including hypoechogencity, irregular shape, macrocalcification, and taller than wide in shape. Microcalciifcation was assigned as 2 points and the remaining features were assigned as 1 point. A composite score was ifnally given to each thyroid nodule ranging from 0 to 6 points. The sensitivity, specificity and accuracy of diagnosing thyroid microcarcinoma by 2DUS composite score method and CEUS were calculated. Results The histopathologic results of all 258 nodules were acquired, including 125 papillary microcarcinomas and 133 benign micronodules. Each nodule′s 2DUS compostie score was ranging from 0 to 6 points. The area of receiver operating characteristic (ROC) curve of 2DUS in diagnosing thyroid microcarcinoma was 0.81. The 2DUS composite score method predicted the thyroid microcarcinoma with sensitivity of 78.4%(98/125), speciifcity of 72.9%(97/133), accuracy of 75.6%(195/258), when the nodule with a score greater than or equal to 3 points was deifned as malignant. Thyroid micronodules′enhancement pattern were divided into 7 types, including early hypoenhancement, hypoenhancement, isoenhancement, hyperenhancement, local nonenhancement, nonenhancement, and ring margin ring enhancement. CEUS predicted thyroid malignant micronodules with sensitivity of 87.2%(109/125), specificity of 75.9%(101/133), and accuracy of 81.4%(210/258), when early hypoenhancement and hypoenhancement pattern was defined as malignant patterns. There were no differences in sensitivity, specificity, and accuracy between 2DUS cumulative score method and CEUS in diagnosing thyroid microcarcinoma (McNemar test, P=0.099, 0.608, 0.096). Conclusion Early hypoenhancement and hypoenhancement are CEUS characteristic enhancement pattern for thyroid microcarcinoma, CEUS has higher sensitivity, speciifcity in diagnosis than 2DUS composite score method, while there are no statistical differences.