Value Of Contrast Enhanced Ultrasonography And Quantitative Analysis In Differentiation Of Small Thyroid Malignant And Benign Nodules

ObjectiveTo evaluate the diagnostic value of contrast enhanced ultrasonogrphy (CEUS) and quantitative analysis in differentiating between small thyroid malignant and benign nodules.Materials and methods51patients with small thyroid nodules were enrolled into this prospective study between October2012and June2013. A total of57small thyroid nodules were evaluated by CEUS, and the final pathology diagnosis was confirmed by fine-needle aspiration or thyroidectomy. The diagnostic yield of enhancement patterns and quantitative parameters were assessed for differentiating between the small malignant and benign nodules. The dynamic images were analyzed by the specific off-line software Qontrast4.00. The results of TTP (Time To Peak), PEAK (peak intensity), RBV (regional blood volume), MTT (mean transit time), SImean (mean of the signal intensity) and SImax (peak of the signal intensity) in different groups were compared between each other by Newman-Keuls Multiple Comparison test (small benign nodules and malignant nodules, small bengin nodules and surrounding tissue, small malignant nodules and surrounding tissue, small malignant nodules and surrouding small benign nodules tissue, small benign nodules and surrouding small malignant nodules tissue).ResultsEnhancement patterns were classified into five types(noncnhancc-ment, early hypo enhancement, hypo enhancement, isoenhanccment, hypcrenhancement). One small malignant and benign nodule had nonenhanccment pattern, and17small malignant nodules had early hypo enhancement pattern, and8small malignant and6benign nodules had the hypo enhancement pattern, and6small malignant and8benign nodules had the isoenhancement pattern, and3small malignant and7benign nodules had the hyperenhancement pattern. There was a significant difference between small malignant and benign enhancement patterns of thyroid nodules(X2=17.076, P=0.002). The PEAK, SImax, SImean of malignant nodules were lower than those of small benign nodules, and all with a significant difference (P<0.05). The PEAK, SImax, SImean RBV of malignant nodules were lower than those of surrounding tissue, and all with a significant difference (P<0.01). The PEAK, SImax、SImean、RBV of malignant nodules were lower than those of surrounding small benign nodules tissue, and all with a significant difference (P<0.05,except SImax P<0.01). For all other parameters, there was no statistically significant difference (P>0.05). Among seven quantitative parameters used to predict small thyroid malignant nodule, peak of the signal intensity (SImax) of lesions had highest value in differentiating between the small malignant and benign nodules with sensitivity of82.8%and specificity of63.2%, and area under receiver operating curve(AUC)of the SImax was0.74.Conclusions Different kinds of small thyriod nodules with different CEUS characteristics, in all quantitative parameters of TIC, PEAK, SImax, SImean can be regard as a significant reference item in the differentiation of small malignant and benign thyriod nodules.