OBJECTIVETo 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.

METHODSWe 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.

RESULTSAmong 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).

CONCLUSIONUnderstanding 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.