Ultrasonic elastography and conventional ultrasound in the diagnosis of thyroid micro-nodules

Objective: To investigate the clinical value of conventional ultrasound, ultrasound elastography and conventional ultrasound combined with ultrasound elastography in differential diagnosis of benign and malignant thyroid micro-nodules.

Methods: Eighty-six patients who were found with thyroid micro-nodules with the maximum diameter no more than 10 mm in the physical examination in our hospital from June 2015 to December 2017 were selected, and 102 nodules were included. All patients were confirmed with thyroid micro-nodules by puncture or surgical pathology and underwent conventional ultrasound and ultrasound elastography. Taking the surgical pathological results as a control, the value of conventional ultrasound, ultrasound elastography and conventional ultrasound combined with ultrasound elastography in differential diagnosis of benign and malignant thyroid micro-nodules were compared. A receiver operating characteristic (ROC) curve was drawn, and the area under the ROC curve was calculated.

Results: One hundred and two thyroid nodules were detected by surgical pathology, including 75 benign nodules (73.53%) and 27 malignant nodules (26.47%). The sensitivity and diagnostic accordance rate of ultrasound elastography were significantly higher than those of conventional ultrasound in the diagnosis of thyroid microcarcinoma, and the missed diagnosis rate of ultrasound elastography was significantly lower than that of conventional ultrasound; the difference was statistically significant (P<0.05). However, the difference between the two methods was not statistically significant in terms of diagnostic specificity and misdiagnosis rate (P>0.05). The areas under the ROC curve in the diagnosis of benign and malignant thyroid nodules by conventional ultrasound and ultrasound elastography were 0.735 and 0.743 respectively.

Conclusion: Conventional ultrasound can be used as a routine examination technique in differential diagnosis of benign and malignant thyroid nodules, while ultrasound elastography can improve the sensitivity and diagnostic rate in the diagnosis of thyroid micro carcinoma. It can help to reduce the clinical missed diagnosis, which also can be be used as an effective supplement for conventional ultrasound.