The Value Of The Quantitative Parameters Of Real-Time Shear Wave Elastography In Differentiating Malignant From Thyroid Benign Nodules

Objective : To investigate the diagnostic value of the quantitative parameters of real-time shear wave elastography(SWE)in differentiating malignant and benign thyroid nodules and SWE was used to obtain the parameters of benign and malignant nodules.Methods:A total of 119 thyroid nodules in 119 patients were included.All thyroid nodules were underwent conventional ultrasound and SWE before fine needle aspiration biopsy and/or surgery in our hospital between July 2017 and June2018.SWE elasticity indices of the maximum(Emax),mean(Emean),minimum(Emin)and SD in thyroid nodules were measured.Repeating the process,at least 3successive measurements were carried out for each nodule by SWE and we got the average statistics of the three-time measurement.The 119 thyroid nodules with histology or cytology were classified into two groups:the benign thyroid nodules and malignant thyroid nodules.The parameters of optimal cut-of values were calculated by using receiver operating characteristic(ROC)curve(AUC).Area of AUC was used to evaluate diagnostic performance in distinguishing thyroid nodules.Group according to the maximum diameter of thyroid nodules(>1cm nodule group and < 1cm nodule group),and then compare whether the size of thyroid benign and malignant nodules will affect the best diagnostic efficiency of Young’s modulus and SD by statistical methods.Results:The final status of the 119 thyroid nodules was benign in 50 and malignant in69.Emax,Emean,Emin and SD of SWE were significantly higher in malignant nodules than in benign nodules(P<0.05).Compared with other SWE parameters,Emax with the optimal cut-off value set at 53.4 kPa had the highest AUC value,showing a diagnostic sensitivity,a specificity,a accuracy,a false negative rate,a false positive rate,a positive predictive value and an negative predictive value of 72.5%,86.0%,69.74%,27.54%,14.0%,87.71%,69.35% respectively.The boundry of the thyroid nodules’ size was 1cm,the difference of Emax and SD between benign nodulesand malignant nodules was statistically significant(P< 0.01).Parameters of Emax and SD of benign nodule groups aren’t statistically significant(P>0.05);The parameter of Emax of malignant nodule groups is statistically significant(P <0.01),but the parameter of SD isn’t statistically significant(P>0.05).P<0.05 was considered statistically siginigicant.Conclusions : 1.The max,mean,min,SD of Young’s modulus had diagnostic performances in differentiating malignant and benign nodules,Compared with other SWE parameters,Emax was most effective and the parameter of SD value was second.2.The boundry of the thyroid nodules’ size was 1cm,parameters of Emax and SD of benign nodules were different from malignant nodules;parameters of Emax and SD of benign nodule groups are statistically significant;the parameter of Emax of malignant nodule groups is statistically significant,but the parameter of SD isn’t statistically significant.