OBJECTIVETo evaluate the efficacy and the limitation of ultrasound-guided core-needle biopsy, ultrasound-guided core-needle aspiration and ultrasound-guided fine-needle aspiration in micro-nodules of thyroid.

METHODSA retrospective was performed in 92 patients with suspectable malignent micro-nodules in thyroid. Of them, 52 patients underwent US-CNB and US-FNA and 40 patients underwent US-CNA and US-FNA. The diagnoses for the micro-nodules were identified by histopathlogical examination after surgery.

RESULTAmong 52 cases with both US-CNB and US-FNA, 41 got nondiagnostic US-CNB and 11 cases successfully got the correct diagnoses of US-CNB; 6 cases got the incorrect diagnosis of US-FNA and 46 cases got the correct diagnosis of US-FNA. Of 40 cases with US-CNA and US-FNA, unsatisfactory specimen of US-CNA occurred in 14 cases and satisfactory specimen of US-CNA were got in 26 cases; unsatisfactory specimen of US-FNA occurred in 4 cases and satisfactory specimen of US-FNA. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of US-FNA in 92 cases for the diagnosis of malignancy were 93.4%, 86.7%, 97.3%, 72.2% and 92.3%, respectively.

CONCLUSIONSUS-FNA is the most valuable method for the diagnosis of suspectable malignent micro-nodules in thyroid before operation.