Objective To explore the application value of acceleration time index（ATI）and ratio of elastic strain rate（SR）in the differential diagnosis of benign and malignant breast tumors.Methods The clinical data of 120 breast tumor patients was analyzed retrospectively.They were divided into benign group（76 cases

98 lesions）and malignant group（44 cases

57 lesions） according to the results of pathological examination. All patients were underwent conventional ultrasound and ultrasound elastography

the ATI and SR values of the two groups were calculated and compared. The receiver operating characteristic（ROC）curve was drawn to analyze the value of ATI

SR and their combination in the differential diagnosis of malignant breast tumors

the area under the curve（AUC） was calculated.Results Two-dimensional ultrasound image characteristics（lesions form

long axis direction

echo intensity

internal echo uniformity

boundary condition

calcification degree

posterior echo intensity）were compared between the two groups

the differences were statistically significant（all P<0.05）.The ATI and SR values of patients in the malignant group were significantly higher than those in the benign group（0.18±0.05 vs. 0.11±0.03

3.05±0.65 vs. 2.33±0.41）

the differences were statistically significant（both P<0.05）.ROC curve analysis showed that the AUC of ATI and SR values for differential diagnosis of malignant breast tumors were 0.842 and 0.813

respectively

and the AUC（0.906）of the combined application was higher than that of the single application（both P<0.05）.Conclusion Both the acceleration time index and SR show good application value in the differential diagnosis of benign and malignant breast tumors

and the combined value of the two is higher.