［Abstract］Objective： To evaluate the influence factors of ultrasound (US)guided percutaneous microwave ablation (MWA) for benign cystic solid thyroid nodules. Methods： From January 2020 to June 2021, a total of 160 patients with benign cystic solid thyroid nodules were included. All patients underwent USguided percutaneous MWA. Each patient was followed up at the 6month after treatment. According to the nodule volume reduction rate (VRR), VRR≥ 50% was defined as significant effective group (122 cases) and VRR<50% as nonsignificant effective group (38 cases). Univariate analysis and multivariate analysis were used to evaluate the factors influencing the VRR of thyroid nodules. Results： Univariate analysis showed that features such as gender, age, body mass index (BMI), nodule size, maximum nodule diameter, nodule morphology, blood flow, and aspect ration were not significantly associated with VRR<50% (all P>0.05). For nonsignificant effective group, nodules located in the risk triangle, nodules being calcified, and proportion of cystic components＜50% were lower than those in the significant effective group (all P<0.05). Based on multivariate analysis, the features of nodule located in risk triangle（OR=26.076,95% CI: 6.983~97.424,P<0.001） and proportion of cystic components＜50%（OR=18.690,95% CI: 5.412~64.605,P＜0.001）were independent risk factors influencing the effect of MWA on benign cystic solid thyroid nodule. The logistic regression equation was established as follows: M=-3.855+(3.261×nodule located in risk triangle)+(2.928×proportion of cystic components＜50%). The associated sensitivity was 78.9% (30/38), specicity was 95.1% (116/122), accuracy was 91.3% (146/160). Conclusion：USguided percutaneous MWA is an effective and safe technique for the treatment of benign cystic solid thyroid nodules. It can significantly reduce the volume of thyroid nodules. The proximity of nodules to the risk triangle and proportion of cystic components＜50% may affect the efficacy of MWA in the treatment of benign cystic solid thyroid nodules.

Objective:To investigate the clinical significance of combined shear wave elastography (SWE) parameters and quantitative analysis parameters of contrastenhanced ultrasound (CEUS) in the differential diagnosis of benign and malignant thyroid nodules. Methods: A total of 71 patients with malignant thyroid nodules and 65 patients with benign thyroid nodules who underwent auxiliary diagnosis in the ultrasound department of Taicang First People′s Hospital from January 2019 to January 2021 were selected. All patients underwent SWE and CEUS. The differences in twodimensional ultrasonographic appearance of benign and malignant nodules, SWE and CEUS parameters in the central area were analyzed.Logistic regression model was used to screen the parameters for judging malignant nodules in SWE and CEUS, the receiver operator characteristic (ROC) curve was drawn using pathological diagnosis as the gold standard, and the area under the curve (AUC) was calculated,and the predictive value of each factor and combined diagnosis of malignant thyroid nodules was analyzed.Results: The twodimensional ultrasonography of benign and malignant thyroid nodules had significant differences in morphology, margin, aspect ratio and microcalcification, and there were differences in central area Emin, Emean, Emax, Peak and AUCt of benign and malignant thyroid nodules (P<0.001). Logistic regression results showed that Emax and Peak entered the regression equation. The ROC curve results showed that among the SWE parameters, the area under the Emax curve was the largest and had the highest diagnostic performance, while Peak was the best diagnostic index in the CEUS parameters, and the AUC value of Emax and Peak in the diagnosis of malignant thyroid nodules was 0.837, which was greater than that of either SWE or CEUS alone.Conclusion:The diagnostic value of Emax and Peak in the central area of thyroid nodules is higher than that of other single parameters, and it has certain guiding significance for the noninvasive examination and diagnosis of thyroid nodules in clinical practice.

Objective： To investigate effects of preoperative ultrasound guidance and intraoperative injection of carbon nanoparticles on lymph node clearance of thyroid papillary carcinoma. Methods： The clinical data of 162 patients undergoing thyroid papillary carcinoma surgery in our hospital were retrospectively analyzed, including 59 patients in the preoperative ultrasound guided group and 103 patients in the intraoperative carbon nano injection group. The number of dissected lymph nodes and the number of detected metastatic lymph nodes in the two groups were analyzed . Results： The numbers  of lymph node clearance, metastasis lymph node detection,<5 mm lymph node clearance,<5 mm metastasis lymph node detection,>5 mm lymph node clearance,>5 mm metastasis lymph node detection, lymph node clearance in central region, the central transfer lymph node detection, lateral neck lymph node clearance， lateral neck metastasis lymph node detection in preoperative ultrasound guided group were higher than those in intraoperative injection group (P<0.05 and P＜0.001).Conclusion：Compared with intraoperative injection group, preoperative ultrasoundguided carbon nanoparticles injection exents better lymph node clearance rate.

［Abstract］Objective： To investigate the value of ACR TIRADS categories in predicting cervical lymph node metastasis in thyroid papillary carcinoma (PTC)patients with Hashimoto′s thyroiditis(HT). Methods： A retrospective analysis was performed in 271 PTC patients with HT. They were divided into metastasis group and nonmetastasis group according to the presence or absence of cervical lymph node metastasis. The differences of preoperative ultrasonography between the two groups were compared, then Kwak TIRADS and ACR TIRADS categories were graded according to the ultrasonography features. Binary logistic regression analysis was performed to determine the independent predictors of cervical lymph node metastasis. The ROC curve was drawn to evaluate the diagnostic efficiency of each factor. Results： Age, sex, maximum diameter, aspect ratio, and ACR TIRADS score were correlated with cervical lymph node metastasis in PTC patients with HT (all P<0.05). Binary logistic regression analysis showed that maximum diameter, ACR TIRADS score and aspect ratio>1 were independent factors for predicting cervical lymph node metastasis（OR=1.169,1.392,2.765, all P<0.05）. The area under ROC curve (AUC) of the combined prediction model was 0.887 (95% CI： 0.849-0.925), the sensitivity and specificity were 86.2% and 75.0%, respectively. Conclusion：ACR TIRADS score is the independent predictor of cervical lymph node metastasis in PTC patients with HT. The combined prediction model can provide some imaging references for clinical treatment.