Impact of thyroid nodule sizes on the diagnostic performance of Korean thyroid imaging reporting and data system and contrast-enhanced ultrasound.

OBJECTIVE: This study aimed to evaluate the impact of thyroid nodule sizes on the diagnostic performance of Korean thyroid imaging reporting and data system (TIRADS) and contrast-enhanced ultrasound (CEUS). METHODS: In total, 308 consecutive patients with 382 thyroid nodules underwent US-guided FNA or surgery were included in this retrospective study. The nodule size was classified into 3 categories: ≤10 mm (group A), 10-20 mm (group B), and ≥20 mm (group C). We compared the risk of malignancy in each subgroup, categorized according to the TIRADS and CEUS patterns. RESULTS: In group A, the differences in diagnostic value between TIRADS and CEUS were significant (AUC: 0.804 vs 0.733, P = 0.028, sensitivity: 81.8% vs 72.7%, P = 0.013, specificity: 88.9% vs 79.4%, P = 0.011). In group B, the AUC (0.897), sensitivity (88.1%) and specificity (91.9%) of CEUS were highest. In group C, the specificity of CEUS was significantly higher compared with TIRADS classification (90.8% vs 82.9%, P = 0.023), while the sensitivity and AUC showed no significant difference between the two models (84.2% vs 81.5%, P > 0.406, 0.848 vs 0.820, P = 0.545). CONCLUSIONS: Nodule size influences the diagnostic accuracy of the two methods. TIRADS have best value in nodules ≤10 mm, while CEUS perform best for differentiating lesions >10 mm, especially in lesions ≥20 mm.

Diagnostic performance of thyroid imaging reporting and data system (TI-RADS) alone and in combination with contrast-enhanced ultrasonography for the characterization of thyroid nodules.

BACKGROUND: The thyroid imaging reporting and data system (TI-RADS), classified and determined the risk of thyroid nodule malignancy with ultrasound scanning. Contrast-enhanced ultrasound (CEUS) is newly developed methods which could measure perfusion features. OBJECTIVE: The aim of the study was to investigate the value of diagnosing thyroid nodules using TI-RADS combined with CEUS and determine whether improvements were made to the diagnostic accuracy. METHODS: The features of conventional ultrasonography (US) and CEUS ion 117 case of thyroid nodules samples, which were confirmed by fine-needle aspiration and/or surgery, were retrospectively analyzed. The independent US and CEUS predictors for malignancy were determined and quantified using logistic regression analysis. The receiver operating characteristic (ROC) curve analysis was used to compare the diagnostic efficiency of each method in predicting malignant solid thyroid nodules. RESULTS: The TI-RADS + CEUS combination had the highest accuracy (94.02%), sensitivity (94.74%), specificity (93.33%), PPV (93.10%) and NPV (94.92%), significantly greater than that of TI-RADS alone and CEUS alone (χ2 = 8.746, P < 0.001; χ2 = 9.825, P < 0.001). The area under the ROC curve (AUC) of TI-RADS alone, CEUS alone, and combined use of TI-RADS and CEUS were 0.871, 0.884, and 0.942, respectively. The following conventional US and CEUS features based on logistic regression analysis showed significant predictive value for thyroid malignant nodules: Obscure margin, calcification, hypoechoic, low enhancement, rim-like enhancement. CONCLUSIONS: TI-RADS in combination with CEUS has superior diagnostic efficiency in the discrimination of benign and malignant thyroid lesions, compared with TI-RADS and CEUS alone.