Sonographic characteristics of high-frequency ultrasound and elastography of thyroid microcarcinoma and the analysis of misdiagnosis / 中华超声影像学杂志

ABSTRACT

Objective To summarize the sonographic characteristics of high frequency ultrasound and elastography of thyroid microcarcinoma(TMC),and to analyze the causes of misdiagnosis.Methods The preoperative ultrasonic data of 245 suspicious TMCs in 202 patients,as confirmed by operation pathology,were retrospectively analyzed.Results Preoperative ultrasonography accurately diagnosed 221 TMCs,the diagnosis rate was 90.2％,and the misdiagnosis rate was 9.8％.Among the missed diagnosed lesions,18 lesions were nodular goiter,others were 3 nodular goiter with focal papillary hyperplasia of follicular epithelium,2 nodular goiter with adenomatous hyperplasia,1 focal lymphocytic thyroiditis,respectively.The thyroid lesions≤0.5 cm in diameter were more easily to misdiagnose.According to the importance of the ultrasonographic features of TMC,the order were aspect ratio (A/T) ≥ 1,irregular-shape,microcalcifications,low or very-low echo.Based on the above corresponding characteristics and considering other features together,the diagnostic accuracy rate were 94.1 ％,93.9％,92.4％ and 90.5％,respectively.Less blood supply and ill-defined boundary were the secondary sonographic signs of TMC.The elastographic scores of TMC were most showed 4 to 5 points.Diagnosis of TMC relied on elastography alone is less effective,but when elastograph diagnosis based on high frequency ultrasound,the diagnostic accuracy is much higher,especially when there is no calcification in the lesions.Conclusions High-frequency ultrasound has a very important value in the diagnosis of TMC,while elastography has certain assistant value on the basis of high-frequency ultrasonic diagnosis.