Comparison of the value of ultrasound-guided fine needle aspiration biopsy and contrast-enhanced ultrasound in different sizes of thyroid nodules

The purpose of this study was to evaluate the diagnostic value of ultrasound-guided fine needle aspiration biopsy (US-FNAB) and contrast-enhanced ultrasound (CEUS) in the presence of thyroid nodules of different sizes. We retrospectively analyzed 110 patients with surgically operated unimodular thyroid nodules in Yichang City Central Hospital from July 1, 2021, to April 1, 2023, all of whom underwent conventional thyroid ultrasound, CEUS, and US-FNAB, and all of whom were classified according to the size of nodules into <0.5, 0.5 to 1, and ≥1 cm groups. The diagnostic accuracy, sensitivity, and specificity of the 2 methods for benign and malignant nodules were calculated. Among 110 thyroid nodules, 102 were malignant nodules and 8 were benign nodules. In patients with nodule diameters <1 cm the sensitivity of US-FNAB and CEUS was 87.02% and 93.89%, respectively, and the specificity was 100.00% and 66.67%, with an accuracy of 87.31% and 93.28%, respectively. In patients with nodule diameter <0.5 cm, the sensitivities of US-FNAB and CEUS were 74.29% and 100.00%, respectively, and the differences were statistically significant (P < 0.05); in patients with nodule diameter 0.5 to 1 cm, the sensitivities of US-FNAB and CEUS were 79.59% and 95.92%, respectively, and the differences were statistically significant (P < 0.05); among patients with nodule diameters ≥1 cm, the sensitivities of US-FNAB and CEUS were 88.89% and 77.78%, respectively, with no statistically significant difference (P > 0.05). For thyroid nodules ≤1 cm in diameter, the sensitivity of CEUS examination was higher than that of US-FNAB; and CEUS still has good diagnostic accuracy in the diagnosis of benign and malignant thyroid nodules <0.5 cm, CEUS is recommended for thyroid nodules diagnosed negatively by US-FNAB with a diameter of <1 cm; and CEUS should be preferred for thyroid nodules with a diameter of <0.5 cm. CEUS should be preferred for thyroid nodules <0.5 cm in diameter.