The Clinical Value Of Contrast-enhanced Ultrasound Combined With Elastography In The Diagnosis Of TI-RADS 4 Thyroid Nodules

Objective:The purpose of this study was to analyze the diagnostic value of contrast-enhanced ultrasound（CEUS）,shear wave elastography（SWE）and their combined diagnosis in the thyroid imaging reporting and data system（TI-RADS）4 of benign and malignant thyroid nodules.Methods:A total of 179 patients with thyroid nodules rated as TI-RADS 4 on ultrasound examination from October 2020 to December 2021,with a total of 211 nodules,were selected for the study and underwent CEUS and SWE examinations respectively,using pathological findings as the gold standard to analyse the CEUS and SWE sonographic features of the nodules,the accuracy,sensitivity and specificity of CEUS,SWE and combined CEUS+SWE were also analyzed and calculated,and the difference in diagnostic accuracy between the three examination methods was compared using the chi-square test.A binary logistic regression model of CEUS combined with SWE was established,and the area under the curve（AUC）was analyzed using the Z-test.The diagnostic efficacy of CEUS,SWE and the combination of the two was compared using the AUC for the diagnosis in the TI-RADS 4 of benign and malignant thyroid nodules.Differences were indicated as statistically significant at P<0.05.Results:1.A total of 211 nodules in 179 patients with thyroid nodules,there were 74benign nodules,including 40 nodular goiter,26 thyroid adenoma and 8 Hashimoto’s nodule;137 malignant nodules,including 126 papillary carcinoma,4 medullary carcinoma,4 follicular adenocarcinoma and 3 undifferentiated carcinoma.2.TI-RADS 4 malignant thyroid nodules on contrast-enhanced ultrasound generally showed hypoenhancement 85.4%（117/137）,centripetal enhancement80.3%（110/137）,inhomogeneous enhancement 81.0%（111/137）,no ring enhancement74.5%（102/137）,and blurred borders 68.6%（94/137）,there was a statistically significant difference between the contrast enhancement patterns of benign and malignant thyroid nodules（P<0.05）.The sensitivity,specificity and accuracy of CEUS in diagnosing TI-RADS 4 thyroid nodules were 87.6%,79.7%and 84.8%,respectively.The cut-off value of 41.85KPa for SWE diagnosis of TI-RADS 4 thyroid nodules,its sensitivity,specificity,and accuracy were 80.3%,86.5%and 82.5%,respectively.The sensitivity,specificity and accuracy of the combined diagnosis of the two methods were 94.9%,89.2%and 92.9%respectively,which were significantly better than those of CEUS and SWE,and the difference was statistically significant（c~2=6.920,P=0.009,c~2=10.616,P=0.001）.3.The AUC for CEUS+SWE,CEUS and SWE were 0.920,0.837 and 0.839respectively,with the combination having the largest AUC and the highest diagnostic efficacy,and all differences were statistically significant（Z=4.100,P<0.0001,Z=3.330,P=0.0009）.Conclusion:Both CEUS and SWE have good diagnostic value for TI-RADS 4 thyroid nodules.They evaluate the nature of nodules from different perspectives.The combined diagnosis of CEUS and SWE has complementary advantages,which significantly improves the diagnosis of TI-RADS 4 thyroid nodules by a single imaging method,it is important for early diagnosis of malignant nodules.