Evaluating the clinical impact of integrating superb microvascular imaging and shear wave elastography into TI-RADS.

Purpose: This study evaluates the diagnostic contribution of Superb Microvascular Imaging (SMI), and Shear Wave Elastography (SWE) to TI-RADS in differentiating benign and malignant thyroid nodules.

Materials and methods: This prospective study enrolled patients scheduled for thyroid fine-needle aspiration biopsy (FNAB). Grayscale ultrasound, SMI, and SWE of the nodules were performed before FNAB. TI-RADS categories, vascularity patterns, vascularity index, and elasticity indices were recorded. Diagnostic performance was analyzed using ROC curves, logistic regression, and the DeLong test.

Results: A total of 478 thyroid nodules were analyzed, comprising 441 (92.2%) benign and 37 (7.7%) malignant cases (35 papillary and 2 medullary carcinomas). The mean age was significantly higher in the benign group (54.61 ± 11.54 years) compared to the malignant group (46.84 ± 15.38 years, p = 0.005). The most common vascularity type was type 3 (48.5% in benign and 81.1% in malignant). Malignancy rates were significantly higher in nodules with vascularity type 3 compared to type 2 (p < 0.001). ROC analysis identified an optimal SWE cut-off value of 36.9 kPa (p < 0.001), but the VI showed no significant difference (p = 0.662). The combined model consisting of TI-RADS score, SWE mean value, and vascularity distribution type demonstrated the highest diagnostic accuracy, with an AUC of 0.89.

Conclusion: Combination of TI-RADS, SMI, and SWE improves diagnostic accuracy in thyroid nodule assessment. Vascularity type 3 and SWE index value are strong, independent predictors of malignancy. The clinical applicability of these tools has the potential to reduce the number of unnecessary biopsies and to improve the management of patients.