Objective To investigate the diagnostic value of real-time ultrasound elastography (RTE) in adjusting the classification of Chinese thyroid imaging reporting and date system (C-TIRADS) classification 4 type nodules. Methods The clinical data of 82 C-TIRADS 4 nodules in 72 patients in the Affiliated Hospital of Yangzhou University from January 2016 to December 2019 were retrospectively analyzed. Conventional ultrasound and RTE examination were performed in all patients before surgery. The nodules were divided into ≤10 mm and >10 mm groups. Using the Asteria RTE scoring method

the C-TIRADS grade of RTE score <3 nodules were downgraded and the score ≥3 nodules were upgraded. The Receiver Operating Characteristic (ROC) curves of before and after RTE adjustments were drawn and the diagnostic efficacies were compared. Results The sensitivity

specificity

accuracy

positive predictive value (PPV) and negative predictive value (NPV) of C-TIRADS in distinguishing benign and malignant thyroid nodules before and after RTE adjustment were 90.4%

56.7%

78.0%

78.3%

77.3% and 96.2%

80.0%

90.2%

89.3%

92.3%

respectively. The corresponding area under the ROC curves were 0.735 and 0.881

respectively (Z=2.869

P=0.004). The diagnostic sensitivity

specificity

accuracy

PPV and NPV were 95.0%

80.0%

88.6%

86.4%

92.3% in the ≤10 mm group and 96.9%

80.0%

91.5%

91.2%

92.3% in the >10 mm group

respectively. The corresponding ROC area under the curves were 0.875 and 0.884

respectively. For ≤10 mm group

the diagnostic efficacy of adjusted C-TIRADS had been significantly improved (Z=3.211

P=0.001). Conclusion C-TIRADS 4 nodules adjusted by RTE can significantly improve its diagnostic efficacy

especially for ≤10 mm nodules.