Objective To compare the values of elasticity imaging(EI)and Virtual Touch TM tissue imaging and quantification(VTIQ)in diagnosing thyroid nodules and explore the factors influencing the accuracy of these two techniques.Methods Totally 62 patients who were planned to receive surgery for thyroid nodules underwent conventional ultrasound,EI,and VTIQ examinations.EI patterns were scored according to the degree and distribution of strain,the strain of nodule and surrounding normal reference tissue were measured,and then strain index was calculated.Shear wave velocity in nodules were obtained under VTIQ mode.Results The nodules were malignant in 40 patients and benign in 22 patients.When the strain score of 3 was regarded as malignant,the diagnostic sensitivity,specificity,and accuracy of EI in detecting thyroid nodules were 90.00%,31.82%,and 69.32%,respectively.Receiver operating characteristic curve results showed that the area under curves of EI-SI and VTIQ methods for diagnosing thyroid nodules was 77.8%(95%CI:0.64-0.91)(P=0.000)and 74.3%(95%CI:0.62-0.87)(P=0.002),respectively.Thyroid nodules' characteristics location(P=0.04)and size(P=0.02)were correlated with the diagnostic accuracy of EI.The accuracy of SI and VTIQ were not affected by thyroid nodules' characteristics(P>0.05).Conclusions The diagnostic accuracy of EI for thyroid nodules is related to nodules' characteristics.EI combined with semi-quantitative SI and quantitative VTIQ can effectively improve the diagnostic capability for thyroid nodules.