Abstract: Liver fibrosis is a ultimate pathological manifestation of various chronic liver diseases, and also an inevitable stage for liver cirrhosis. However, how to accurately diagnose liver fibrosis has always been a challenge and research hotspot in the clinical setting. Although liver biopsy remains the gold standard for the diagnosis of liver fibrosis, its application is limited by its invasiveness, relatively high risk potential complications such as bleeding, infection, and rupture of organs, high cost, low patient's acceptance and it is not suitable for repeatable test, which limited the surveillance for liver fibrosis in the follow-up. In recent years, how to noninvasively and accurately stage liver fibrosis has become a new research hotspot. And ultrasound elastography, as a diagnosis technique combining a new type of medical imaging and biomechanics is characterize for its non-invasiveness and simpleness, advantage of real-time visualization and its quantitative nature, which can be used to quantitatively evaluate liver stiffness. As a result, it was extensively used to stage fibrosis of chronic liver disease and to evaluate the liver stiffness after liver transplantation. Also, it could be integrated into the guidance for clinical treatment prognosis assessment, and dynamic surveillance for the patients. This article briefly introduces the technique principles, latest developments, application status, and challenges of ultrasonic elastography.

Key words: Ultrasonic elastography, Liver fibrosis, Liver stiffness, Liver allograft