RESUMO
<p><b>OBJECTIVE</b>To seek for the ultrasound findings of thyroid nodules related to malignancy and benign, and to assess the role of TI-RADS in the ultrosound evaluation of thyroid nodules.</p><p><b>METHODS</b>We reviewed and analyzed the ultrasound characteristics of 1838 thyroid nodules confirmed by biopsy or surgical pathology, classified the thyroid nodules by TI-RADS grading criteria, and analyzed the malignancy rate and accuracy rate of different TI-RADS grading.</p><p><b>RESULTS</b>Among the 1 838 thyroid nodules, 1 160 cases were carcinomas confirmed by surgery, while benign nodules in 212 cases. The sensitivity, specificity, PPV, NPV, and accuracy rates were 99.7% (1 156/1 160), 41.0%(278/678), 74.3% (1 156/1 556), 98.6% (278/282), and 78.2% (1 434/1 838), respectively. There were significant differences between the malignant and benign thyroid nodules in echo, margin, shape, calcification, and blood flow (P<0.001). Hypoechogenicity, marked hypoechogenicity, ill-defined margin, microcalcification, a taller-than-wide shape, and nodule internal rich flow (type III) were significantly associated with malignancy, while hyper/isoechogenicity, smooth margin, macro/no-calcifications, a wider-than-tall shape, and nodules internal poor flow (type I or type II) were significantly associated with benign nodules. There were significant differences between the malignant rates and accuracy rates obtained by different TI-RADS classifications (P<0.01).</p><p><b>CONCLUSION</b>Understanding the ultrasound characteristics of benign and malignant thyroid nodules and applying TI-RADS grading criteria to correctly classify the thyroid nodules are crucial for the clinical treatment and prognosis.</p>