Research on mechanism and influencing factors of mirror-image artifact of color Doppler flow beside pulmonary artery

Objective To explore the mechanism and influencing factors of mirror-image artifact of color blood flow (MACBF) due to longitudinal strong echo big interface (LSEBI). Methods Fifty suspicious patients with MACBF beside the main pulmonary artery and/or the left pulmonary artery undergoing echocardiography examination from November 2018 to April 2019 in Shengjing Hospital of China Medical University were chosen as the subjects. Image characteristics of the MACBF were observed, and mechanism and influence factors of the MACBF were explored with Doppler imaging principle. Results Of all the subjects with MACBF, 36 subjects occurred only on the left side of the main pulmonary artery, 14 subjects occurred on both the left side of the main pulmonary artery and the left pulmonary artery. The LSEBI was found between the real color blood flow (RCBF) and the MACBF, there was a mirror relationship between the RCBF and the MACBF. The LSEBI on the left of the main pulmonary artery and the left pulmonary artery were the interface of the left lung and pleural. The signal strength of MACBF enhanced as the distance between the blood flow and the LSEBI got closer or the gain of the color blood flow got bigger. Conclusions MACBF may caused by LSEBI beside vessel. The formation of MACBF and its signal strength are influenced by the distance between blood flow and LSEBI and the gain of the color blood flow. Key words: Ultrasonography; Mirror-image artifact; Color Doppler flowing imaging