As the most advanced ultrasound imaging technology, ultrasonography is known as a non-invasive microcirculatory angiography. It can provide richer and clearer diagnostic information than conventional ultrasound and color Doppler ultrasound. It enhances the body’s blood flow signal by intravenous injection of ultrasound contrast agent on the basis of conventional ultrasound examination, and dynamically observes the microvascular perfusion information of tissues in real time to improve the detection rate of lesions and to discriminate the benign and malignant nature of lesions. The whole examination process is quite short, about 10 minutes to complete, and is a new imaging technique that is non-invasive and free of ionizing radiation. Ultrasonography requires the use of an ultrasound contrast agent. Ultrasound contrast agent is a microbubble suspension that can be circulated through the lungs. When microbubbles are injected into human blood, the blood flow signal is significantly enhanced, which significantly improves the display of small vessels and low flow rates, providing rich blood flow information for diagnosis. This enables physicians to observe the perfusion of normal organs and masses in real time and dynamically, improving the specificity and sensitivity of ultrasound diagnosis. After the contrast agent is injected through a peripheral vein, it reaches the target tissue with the blood circulation to visualize the lesion, and then the gas inside the microbubble is quickly exhaled through the lungs. It has been used in hundreds of thousands of patients at home and abroad, with minimal toxic side effects, safe and reliable, and no allergy test is required. At present, the contrast agent used in domestic ultrasonography is sulfur hexafluoride microbubble for injection, which is a very safe microbubble suspension preparation with an average diameter of microbubbles smaller than that of red blood cells, and is eliminated from the body through breathing (almost all the gas is expelled after 15 minutes). Since all components of the product are non-toxic, the incidence of adverse reactions is extremely low, there is no nephrotoxicity or cardiotoxicity, and ultrasonography is a safe and reliable clinical diagnostic technique.