Comparative Study Of Smi And ACR TI-RADS Classification In The Diagnosis Of Benign And Malignant Thyroid Nodules

Objective: To explore the diagnostic efficacy of super micro-vascular imaging(SMI)technique and American College of Radiology Thyroid Imaging Report And Data System(ACR TI-RADS)classification in benign and malignant thyroid nodules.Methods: 62 cases of thyroid nodules were examined by color Doppler ultrasound and SMI,and the nodules were graded according to ACR TI-RADS classification.The diagnostic efficacy of SMI,ACR TI-RADS classification alone or in combination with each other was analyzed with pathological results as gold standard.Results: There were 21 benign nodules(31.82%)and 45 malignant nodules(68.18%).The maximum diameter of benign nodules was significantly higher than that of malignant nodules [(2.44±1.16)cm vs(1.54±1.24)cm,P<0.05].The proportion of TR3 in benign thyroid nodules was the highest(71.43%),and that in malignant nodules was the highest(75.56%).There was significant difference in ACR TI-RADS classification between benign nodules and malignant nodules(P<0.05).The malignant rates of TR3,TR4 and TR5 were 7.14%,71.43% and 94.44%,respectively.The mean RI of blood flow in benign nodules was 0.60 ± 0.14 and that of malignant nodules was0.75 ± 0.12 in SMI mode.The RI value of malignant nodules was significantly higher than that of benign nodules(P<0.05).Regarding the distribution of blood flow in the nodules,The blood flow distribution in benign nodules was mainly peripheral type(61.90%),while that in malignant nodules was mainly in central type(57.78%).The distribution of peripheral blood flow was mainly distributed in benign nodules(22.43%).ROC curve showed that the best cut-off value of ACR TI-RADS for the diagnosis of malignant thyroid nodules was ≥ 6 points,and the optimal threshold value of SMI was RI ≥ 0.62.Compared with ACR TI-RADS and SMI alone,ACR TI-RADS + SMI had higher diagnostic efficiency for malignant thyroid nodules(AUC=0.934),and the diagnostic specificity was significantly higher than that of ACR TI-RADS and SMI alone(P< 0.05).Conclusion: 1.Thyroid Imaging Report and Data System(ACR TI-RADS)classification method has higher sensitivity and accuracy,and the malignant rate of thyroid nodules increases significantly with the increase of grading.2.The blood flow distribution of benign nodules is peripheral,the edge is mainly circular,the blood flow distribution of malignant nodules is the inner central type,and the edge is mainly concentrated.3.The blood flow RI value of malignant thyroid nodules in SMI mode is significantly higher than that of benign nodules.4.SMI and ACR TI-RADS classification have high sensitivity and accuracy in the diagnosis of benign and malignant thyroid nodules,and the combined application of both can significantly improve the diagnostic rate.