Suggested amendment of TI-RADS classification of thyroid nodules by shear wave elastography

Abstract

Background

The application of the ultrasound elastography and Thyroid Imaging Reporting and Data System (TI-RADS) classification further expands the scope of ultrasound differential diagnosis between benign and malignant thyroid nodules.

Purpose

To investigate the value of the quantitative parameter of ultrasonic shear waves in optimizing the TI-RADS classification of thyroid nodules.

Material and Methods

A total of 168 thyroid nodules, initially classified using TI-RADS and scanned by shear wave elastography (SWE), were retrospectively analyzed. All cases were diagnosed by fine needle aspiration and histology following surgery.

Results

The benign rate of TI-RADS 3 nodules was 76.5%, while the benign rate of TI-RADS 4a nodules was 71.7%. Furthermore, the malignant rate of TI-RADS 4b nodules was 69.7%, while the malignant rate of TI-RADS 4c nodules was 85.7%. In differentiating benign from malignant nodules, the combination of TI-RADS classification and E_mean had the largest area under the receiver operating characteristic curve (AUC). Using an E_mean value of 42.25 kpa as the cut-off point, the malignant rate of TI-RADS 4a nodules decreased from 28.3% to 23.5%, while the malignant rate of TI-RADS 4b nodules increased from 69.7% to 79.4%. Compared to conventional ultrasound alone, the sensitivity, negative predictive value, and AUC of conventional ultrasound combined with SWE in the diagnosis of benign and malignant thyroid nodules significantly improved (P=0.012, 0.029, 0.001).

Conclusion

The SWE technique can be used to further determine the benign and malignant nature of TI-RADS 4 lesions, providing further reference for the choice of clinical treatment. The TI-RADS classification system corrected by SWE is more significant in the diagnosis of benign and malignant thyroid nodules.