Ultrasonography, also known as Contrast-enhanced Ultrasound (CEUS), is a new ultrasound technique that has been developed in the last decade and has revolutionized ultrasonography. With the intravenous injection of ultrasound contrast agent, the ability of ultrasound to detect tissue perfusion is greatly enhanced, and the fine vascular structures of normal and diseased tissues can be clearly displayed, thus providing important diagnostic information. Because ultrasonography is simple, economical, efficient and safe, it is now widely used in clinical practice. Indications for CEUS examination: From the perspective of ultrasonography, ultrasonography can be considered for anyone who can clearly show lesions on general ultrasound but has difficulty in qualitative diagnosis. Ultrasonography is especially suitable for qualitative diagnosis of focal liver lesions, exploration of focal liver lesions, determination of the efficacy of ablation of liver tumors, diagnosis of trauma to abdominal organs, and diagnosis of lesions in various organs such as gallbladder, bile duct, pancreas, spleen and kidney. Contraindications to CEUS: In terms of the use of contrast agents, the patient should be between 18 and 80 years of age and should be free of allergies, severe cardiopulmonary disease or hypertension, as well as being pregnant or breastfeeding. In addition, an informed consent form must be signed prior to the examination. Ultrasound contrast agent: SonoVue (Bracco, Italy) is currently used in mainland China, the main component of which is sulfur hexafluoride (SF6) gas microbubbles wrapped by phospholipids and polyethylene glycol, with an average diameter of 2-3 μm, more than 90% < 8 μm, and a concentration of (1-5) × 108/ml. In the body, SF6 is exhaled through the lungs, phospholipids are involved in metabolism, and polyethylene glycol is cleared by the kidneys. Polyethylene glycol is cleared by the kidney. The commercial package is lyophilized powder, 59mg/bottle, when used, inject 5ml of sterile saline into the bottle and shake vigorously until it becomes a homogeneous suspension. The ultrasound contrast agent is different from the iodine contrast agent used in CT, there is no iodine allergy and no allergy test is needed before contrast. The examination method of CEUS: First, routine ultrasound examination is performed to understand the location, size, shape, boundary, and echogenic characteristics of the lesion. Following this, color Doppler and spectral Doppler are used to detect the blood flow characteristics of the lesion. Finally, ultrasonography is performed via intravenous injection of ultrasound contrast agent. The whole procedure takes about 15-30 minutes. Patients generally do not need special preparation before the examination, but need to fast from food and water for more than 8 hours before the ultrasonography examination of gallbladder and pancreatic lesions; during the examination, patients need to give appropriate breathing cooperation to the doctor; after the examination, need to observe for at least 15 minutes and report to the doctor in time if they feel panic, chest tightness and other discomfort. The efficacy of CEUS examination: ultrasonography has greatly improved the qualitative diagnostic ability of ultrasonography for a variety of lesions in the liver, gallbladder, pancreas and kidney, especially for a variety of benign and malignant liver lesions with an accuracy rate of more than 90%, comparable to CT or MRI. Many liver lesions diagnosed by CEUS do not require repeat CT or MRI examinations. At the same time, ultrasonography is safe, cost-effective and efficient, with an adverse reaction rate of less than 0.1% and a cost of only 40% to 50% of that of CT or MRI, with enhanced images and reports available immediately without waiting.