The value of superb microvascular imaging (SMI) scoring assignment method in differentiating benign and malignant thyroid nodules by conventional ultrasound

PURPOSE: To explore the application value of SMI scoring assignment method combined with 2017 American College of Radiology (ACR) Thyroid Imaging, Reporting and Data System (TI-RADS) in differentiating benign and malignant thyroid nodules. METHODS: According to the 2017 ACR TI-RADS classification, the enrolled nodules were divided into 3 points group, 4 points group, 5 points group, 6 points group and >= 7 points group. The nodules were assigned scores according to the echocity of the nodules and the microvessels detected by SMI and their distribution patterns based on ACR TI-RADS. Accompany with the scores increased or decreased after assignment, the thyroid nodules were re-grouped. RESULTS: The AUC after the scores assignment is better than before (Z=3.881, P< 0.001). The specificity, positive predictive value and accuracy after score assigned are better than those of before (Z = 8.323, P< 0.001; Z = 8.619, P< 0.001; Z =5.345, P< 0.001), there is no statistical difference in sensitivity before and after score assigned (Z = -0.513, P = 0.60), and the negative predictive value before assigned score is better than that of after (Z = -3.826, P< 0.001). CONCLUSION: The diagnostic efficacy after scoring was better than that of before.