The characteristics and value of ultrasonography in the diagnosis of thyroid microcarcinoma / 中华超声影像学杂志

ABSTRACT

Objective To investigate the role of gray-scale sonography in the diagnosis of thyroid microcarcinoma(TMC).Methods The sonographic characteristics of 58 TMC and 61 benign thyroid nodules(≤1 cm)were retrospectively reviewed and compared with each other.The size,echogenicity,internal solid/cystic component,configuration,anteroposterior to transverse dimension ratio(A/T),margin,halo sign and calcification type of the nodules were studied.Statistical analysis was performed using the chi-square test.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of individual sonographic characteristics were calculated respectively.Results In ultrasonography,TMC manifested as marked hypoechoic in 48.3%,solid lesion in 98.3%,irregular-shape in 74.1%,irregular halo sign in 37.0%,with internal microcalcifications in 62.1%.There were significantly statistical differences between the benign and malignant nodules in those findings (P＜0.001).However,there was no obviously statistical difference in the obscure margin.The sensitivity,specificity and accuracy were 86.2%,77.0% and 81.5% respectively when using marked internal hypoechoic echo,A/T≥1 and microcalcification as a new combined criterior.Conclusions The gray-scale sonographic findings between the small benign and malignant thyroid nodules(≤1 cm)are different.Combining these sonographic signs can significantly improve diagnostic value of TMC.