Real-time Shear Wave Elastography For Eva Luating TI-RADS 3-5 Nodules Diagnostic Value And Influencing Factors

Objective: To analyze the diagnostic value of real-time shear wave elastography(SWE)in thyroid imaging reporting and data system(TI-RADS)3-5 nodules,and to explore the influencing factors of SWE in differentiating benign and malignant TI-RADS 3-5 nodules.Methods:123 TI-RADS 3-5 thyroid nodules were selected for fine-needle aspiration(FNA)or surgical resection.All patients underwent routine ultrasonography and SWE examination.The pathological results were taken as gold standard.The results were compared with those of FNA puncture or surgery.The receiver operating characteristic curve(ROC curve)was drawn.The truncation values of SWE for benign and malignant diagnosis of thyroid nodules were obtained.The Emax,Emean and discrete values were compared.The area under curve(AUC)of four parameters,standard deviation(SD)and Ratio value(mean nodule/mean thyroid tissue),was calculated to evaluate the sensitivity,specificity,accuracy,positive predictive value,negative predictive value and AUC of SWE in differential diagnosis of TI-RADS 3-5 nodules.Elastic image typing of thyroid nodules was analyzed and the difference between benign and malignant thyroid nodules was compared.Using binary logistic regression model,the possible influencing factors were evaluated,and the influencing factors of differential diagnosis of TI-RADS 3-5 nodules by Emax value were analyzed.Result: Using pathological results as the gold standard for diagnosis,the areas under the curves of Emax,Emean,SD and Ratio of real-time shear wave elastography were 0.873,0.792,0.811 and 0.762,respectively.The optimal truncation values were 40.8 kpa,22.9 kpa,5.15 kPa and 2.55 kpa.The sensitivity was 86.8%,79.2%,81.1%,66.0%,and the specificity was 88.6%,75.7%,68.6%,85.7 kpa,respectively.The positive predictive values were 83.6%(46/55),70.7%(41/58),66.2%(43/65),77.8%(35/45),and the negative predictive values were 89.7%(61/68),81.5%(53/65),82.8%(48/58)and 76.9%(60/78),respectively.Emax value had better sensitivity,specificity,positive predictive value,negative predictive value and AUC in judging benign and malignant lesions,higher than Emean value,SD and Ratio value.Elastic images of benign nodules were mainly negative,vertical bright bands or spots.Malignant nodules were mainly multicolor lesions,hard rings and absent center.The sensitivity,specificity and accuracy of diagnosis were 81.1%,88.6% and 85.4%,respectively.The binary logistic regression analysis showed that the presence of calcification and diffuse thyroid lesions could affect the Emax value in the diagnosis of benign and malignant TI-RADS 3-5 thyroid nodules.Conclusion: SWE can be used to differentiate benign and malignant TI-RADS3-5 nodules qualitatively and quantitatively.The main factors affecting the differential diagnosis of TI-RADS 3-5 nodules by real-time SWE with or without diffuse thyroid lesions and calcification.Comprehensive analysis of the relevant factors of real-time SWE can improve the application value and reduce the diagnostic error.