Abstract: Objective The aim of this study was to investigate the clinical value of contrast enhanced ultrasonography(CEUS)combined with acoustic radiation force impulse(ARFI)in the diagnosis of peripheral pulmonary masses. Methods A total of 51 peripheral lung diseases patients who were confirmed by surgical or biopsy pathology in the Second Affiliated Hospital of Harbin Medical University from January 2019 to June 2021 were retrospectively studied,and their focus related data in routine ultrasound,CEUS and ARFI examinations were analyzed.The diagnostic performance of CEUS,ARFI,and their combination in differentiating benign and malignant masses was evaluated and compared. Results There was a significant difference between benign and malignant groups in whether the tumor was round or not under conventional ultrasound(P＜0.01).The rise time(RT)of malignant tumors in CEUS was longer than and the time to peak(TTP)was shorter than that of benign lesions(P＜0.05).In ARFI examination,the shear wave velocity(SWV)of malignant masses was significantly higher than that of benign masses(P=0.04).The sensitivity,specificity,and accuracy of diagnosing malignancy in CEUS were 77.4%,85.0%,and 72.5%,respectively,when the occupied RT and TTP exceeded 10.5s and 19.5s,respectively.The sensitivity,specificity and accuracy of diagnosing malignancy in ARFI examination were 83.9%,50.0% and 70.6%,respectively,with a mean SWV ＞2.02 m/s.CEUS and ARFI met at least one of the criteria,with a sensitivity of 96.8%,a specificity of 40.0%,and an accuracy of 74.5% to determine malignant lesions. Conclusion CEUS combined with ARFI is more sensitive and accurate in the diagnosis of peripheral benign and malignant lung masses,and can effectively reduce the rate of missed diagnosis.

Key words: Lung cancer, Peripheral pulmonary mass, Contrast enhanced ultrasonography, Acoustic radiation force pulse imaging