Arachnoid cysts are benign cranial lesions that are often caused by abnormalities in the developing arachnoid membrane, as well as by infection and trauma. They are most often located on the surface of the brain and are common in single or multiple cases. It is often detected during CT or MRI of the head due to trauma or other causes. Most scholars believe that surgery is not necessary for those without clinical symptoms. For symptomatic patients, surgical treatment is required for internal decompression of the cyst and removal of the cyst wall, and the treatment modalities are as follows: 1. Drainage of the cyst: (1) Internal drainage of the cyst fluid into the subdural cavity. (2) Cyst-abdominal shunt to drain the cystic fluid into the abdominal cavity. 2.Cyst wall dissection: (1) craniotomy to remove the cyst. (2) Various endoscopic techniques as well as laser-assisted techniques to remove the cyst. (3) Drilling or needle aspiration to drain the cystic fluid. 4.Medication for epilepsy or painful symptoms.