Value of strain elastography and shear wave elastography in the diagnosis of benign and malignant thyroid nodules

Objective To compare the value of strain elastography (SE) and shear-wave elastography (SWE) in the diagnosis of benign and malignant thyroid nodules.

Methods A total of 109 patients with single solid thyroid nodules who were examined by ultrasound and confirmed by puncture biopsy or surgical pathology from March 2021 to March 2023 were selected as study subjects. All patients underwent SE and SWE examinations. Pathological results were taken as the "gold standard" for diagnosis, and the mean value of SE strain (SE_mean), the ratio of the mean strain of surrounding normal thyroid tissue to the mean strain of thyroid nodule (SR), elastic mean value of Young's modulus of SWE (E_mean) and ratio of the average elasticity of thyroid nodule to the average elasticity of surrounding normal thyroid tissue (ER). The value of the two elasticity techniques in differentiating benign and malignant thyroid nodule was compared, and the correlations of SE_mean and SR with E_mean and ER.

Results The pathologic examination of 109 patients with thyroid nodules confirmed that 69 cases(benign group) were benign and 40 cases (malignant group) were malignant. The maximum diameter of nodules in the malignant group was significantly smaller, and the proportion of patients with nodular aspect ratio>1, unclear boundary, solid hypoecho and lack of blood supply was higher than that in the benign group (P < 0.05). There were no significant differences in age, gender and the proportion of small calcification inside nodules between two groups (P>0.05). SR, E_mean and ER in malignant group were higher than those in benign group (P < 0.05). Receiver operating characteristic (ROC) curve analysis showed that the area under the ROC curve (AUC) of SE_mean and SR were 0.902 and 0.884, which were higher than 0.795 of E_mean and 0.806 of ER (P < 0.05). SE_mean was negatively correlated with E_mean and ER (r=-0.689 0, -0.634 9, P < 0.05), and SR was positively correlated with E_mean and ER (r=0.537 2, 0.688 3, P < 0.05).

Conclusion SE and SWE have certain clinical application value in differentiating benign and malignant thyroid nodules, but SE technique has a high diagnostic efficiency. The two techniques have shortcomings, and they can be complementary in practical application to improve the diagnosis efficiency of benign and malignant thyroid nodules.