Liver cysts are one of the most common benign diseases of the liver and are not tumors, although they are an occupying lesion. Liver cysts are divided into two categories: parasitic cysts and nonparasitic cysts. Parasitic liver cysts are caused by parasites, such as encapsulated cysticercosis in pastoral areas. Non-parasitic liver cysts are the most common and clinically referred to as non-parasitic liver cysts, both congenital and acquired. Acquired hepatic cysts are: (1) hematoma and degenerative cysts; (2) lymphatic cysts; (3) retention cysts due to bile duct obstruction; and (4) cystic adenomas. Of these, retention cysts are the most common and are mostly due to inflammation, edema, scarring, trauma, and puncture. The majority of congenital liver cysts seen clinically are due to abnormal development of intrahepatic bile ducts or lymphatic vessels during the embryonic period. Liver cysts are also classified as monogenic or multiple. Solitary hepatic cysts are often located in the right lobe of the liver and are more commonly seen in women. Multiple hepatic cysts are more common and may invade the left and right hepatic lobes and may be combined with polycystic kidneys. Liver cysts grow slowly and may be asymptomatic for a long time or for life, and their clinical manifestations vary with the location, size, number and presence of complications. When the cyst increases to a certain extent, it may compress adjacent organs, such as stomach, duodenum and colon. Symptoms usually appear after 40-50 years of age, most of them are mild, with occasional painless masses in the upper abdomen, or distension and pain in the liver area, loss of appetite, belching, nausea, vomiting, and wasting. If the cyst enlarges and presses on the common bile duct, there is jaundice, rupture may have intracapsular bleeding, and torsion of the cyst with tip may have acute abdominal pain, mostly in the upper abdomen or right rib cage, sometimes radiating to the shoulder, back or chest. The liver is enlarged but no pressure pain. About half of the patients have polycystic lesions of kidney, spleen, ovary and lung. There is chills, fever and elevated white blood cells in case of intracapsular infection. Liver cysts mainly rely on imaging diagnosis, with ultrasonography being the most important. b-mode ultrasonography has a detection rate of up to 98% for liver cysts. In terms of characterization, ultrasonography is more accurate than CT; however, CT is superior to B-mode ultrasonography in fully understanding the size, number and location of cysts and related organs in the liver and around the liver, especially for huge liver cysts that require surgical treatment. Simple and non-invasive B-mode ultrasonography should be performed first, which can also identify liver cysts. Next, X-rays should be selected as needed, including abdominal plain film, abdominal arteriography, gastrointestinal imaging, CT and MRI. Ultrasound or CT is very reliable in diagnosing liver cysts, so there is no need to do too many tests. The number of cysts found during ultrasound or CT examination, especially ultrasound, is sometimes more and sometimes less, because of the limitation of the examination equipment or the carefulness of the examiner, and one less does not mean good, and one more does not mean bad. Liver cysts do not become malignant. So far, the formation of liver cysts has not been found to be related to certain foods, so patients with liver cysts do not need to avoid eating. It is also not found that doing housework, sports and work have a promoting effect on the growth of liver cysts, so patients with liver cysts do not need to change their living habits and working environment, they can work and exercise, and there is nothing to pay special attention to in their life. Most of the liver cysts do not need special treatment, and single or multiple cysts without clinical symptoms do not need treatment and should be examined by ultrasound regularly. Special treatment should be considered in the following cases: (1) those with cysts over 5 cm or patients with certain clinical symptoms; (2) giant liver cysts: a few liver cysts grow faster and when the diameter exceeds 10 cm, they are called giant liver cysts. Giant liver cysts can cause compression symptoms, affect life and work, and should be considered for treatment; (3) Cyst secondary infection: liver cysts are usually rarely secondary to infection, but a few liver cysts can be secondary to infection. These patients may have inflammatory manifestations such as pain in liver area, fever, elevated blood leukocytes, etc. Ultrasound examination may show thickened cyst wall, liquid dark area and mixed enhanced light spots (suggesting pus). These patients should be treated promptly; (4) Cyst secondary hemorrhage: a few liver cysts may have spontaneous rupture of the cyst wall vessels leading to intracapsular hemorrhage, some without obvious symptoms, some with severe pain in the liver area, such as conservative treatment without effect surgical treatment; (5) Cyst torsion: torsion of overhanging cysts produces severe pain and requires laparoscopic or surgical treatment. There are three treatments for liver cysts: (1) puncture and drainage + injection of sclerosing agent; (2) surgical open cystotomy; (3) laparoscopic cystotomy. Each of the three treatments has advantages and disadvantages; puncture and sclerotomy can have a recurrence rate if not done properly, open surgery is traumatic and slow to recover, and laparoscopy is costly and also traumatic. In fact, the latter two treatments also have a higher recurrence rate, and those with problems need to discuss in detail with their doctors and choose after weighing the pros and cons. Currently, there are two main minimally invasive treatment modalities for simple liver cysts: B-ultrasound or CT-guided percutaneous puncture sclerotherapy and laparoscopic liver cyst opening. Percutaneous puncture cyst drainage + sclerotherapy for liver cysts is one of the most minimally invasive methods that does not leave any scars. The principle is that the cuboidal epithelium in the cyst wall has the function of secreting cystic fluid, and the cystic fluid is drained and injected with sclerosing agent, which can cause protein coagulation and denaturation of the epithelial cells in the cyst wall and cell destruction, resulting in sterile inflammation and closure of cystic cavity adhesions. Laparoscopic hepatic cyst windowing is another treatment modality, and most tertiary hospitals in China can carry out this kind of surgery. Theoretically, after laparoscopic hepatic cyst debulking, some of the cyst wall epithelium remains, and the cyst may still recur. Especially if the cyst is deeply embedded in the liver parenchyma and it is impossible to remove most of it, the possibility of recurrence is even greater. In contrast, as long as the cyst wall can fully contact with the sclerosing agent and coagulate, there is almost no possibility of recurrence. The recurrence is caused by improper operation. Therefore, first of all, the cyst fluid must be pumped out, otherwise the cyst fluid will dilute the sclerosing agent affect the efficacy, to pump out the cyst fluid is best to use a side hole puncture needle, ordinary long needle is not easy to do. Secondly, repeated flushing of sclerosing agent is also an important method to ensure the efficacy of the treatment, which can reduce the possibility of dilution of sclerosing agent and keep the alcohol concentration in the sac above 40%. Thirdly, it is better to use the placement method for cysts larger than 10 cm in diameter, and sclerotherapy can be done once again after adequate drainage to ensure the efficacy. Therefore, hepatic cyst puncture and sclerotherapy under the guidance of ultrasound or CT is easy to perform, safe and effective, without complications, inexpensive, with minimal trauma and quick recovery for patients, and it is a practical interventional treatment method, especially for patients with recurrence after open surgery and laparoscopic surgery, and is the first choice for treating hepatic cysts. The following is one of the cases we treated for your reference: