Value of biopsy by contrast-enhanced ultrasound in diagnosis of nature of type 4 thyroid nodules by thyroid imaging reporting and data system

Objective To investigate the value of contrast-enhanced ultrasound (CEUS) guided fine needle aspiration (FNA) in diagnosing the nature of type 4 thyroid nodules by thyroid imaging reporting and data system (TI-RADS).

Methods A total of 120 patients with TI-RADS type 4 thyroid nodules were selected as subjects. Sixty patients underwent CEUS-guided FNA (CEUS group), while the other 60 patients underwent conventional ultrasound-guided FNA (conventional ultrasound group). Using pathological results as the gold standard, Kappa consistency tests were used to analyze the diagnostic consistency of conventional ultrasound-guided FNA and CEUS-guided FNA for TI-RADS type 4 thyroid nodules.

Results Among 120 patients with TI-RADS type 4 thyroid nodules (138 nodules), 85 malignant nodules and 53 benign nodules were confirmed by pathology. In the CEUS group, there were 28 benign nodules and 42 malignant nodules (40 papillary thyroid carcinomas and 2 medullary carcinomas). In the conventional ultrasound group, there were 25 benign nodules and 43 malignant nodules (39 papillary thyroid carcinomas and 4 medullary carcinomas). The false positive rate and false negative rate of conventional ultrasound-guided FNA for diagnosing malignant TI-RADS type 4 thyroid nodules were 3.62% and 5.07%, respectively. For CEUS-guided FNA, the rates were 2.17% and 2.90%, respectively. The sensitivity, specificity and accuracy of conventional ultrasound-guided FNA for diagnosing the nature of TI-RADS type 4 thyroid nodules were 83.72%, 80.00% and 82.35%, respectively, with Kappa value of 0.627. For CEUS-guided FNA, these values were 90.48%, 89.29% and 90.00%, respectively, with Kappa value of 0.793. Based on pathological examination, the diagnostic agreement rates for malignant TI-RADS type 4 thyroid nodules were 79.07% for conventional ultrasound-guided FNA and 83.33% for CEUS-guided FNA, with Kappa values of 0.719 and 0.786, respectively.

Conclusion CEUS-guided FNA can provide high-resolution, real-time dynamic imaging information, thereby improving the sensitivity and specificity of diagnosing the nature of TI-RADS type 4 thyroid nodules.