Intracranial arachnoid cysts are cystic cavities formed by cerebrospinal fluid surrounded by the arachnoid membrane and are benign lesions. Arachnoid cysts are commonly found in the lateral fissure, longitudinal fissure, surface or base of the brain, and cerebellum, as well as in the saddle area, optic nerve, tegmental area, slope, and pontocerebellar horn. There are two clinical types: congenital intra-arachnoid cysts, which are caused by abnormal development of the embryonic arachnoid membrane and account for the majority of cases; and secondary arachnoid cysts, which are the result of extensive adhesions to the arachnoid membrane caused by trauma and inflammation. The main manifestations of the patient are similar to other intracranial occupying lesions, but the entire course of the disease progresses slowly and can remain in a relatively stable state for a long time. The main manifestations include impaired consciousness, progressive sensory disturbances, various cerebral nerve dysfunctions, etc. Some patients may have mild paralysis or seizures. Cysts located in the optic chiasm, i.e., the saddle area, may cause visual acuity loss and visual field changes. . The presence or absence of progression of the cyst goes hand in hand with the development of symptoms. Lateral fissure arachnoid cysts are most common in young children and may present with temporal skull augmentation, temporal bone thinning, and chronic intracranial pressure increase, but they go unnoticed until adulthood when symptoms develop. Symptoms are related to the size of the cyst and the site of growth. Small cysts may be asymptomatic and are occasionally found at autopsy. Many patients with congenital arachnoid cysts progress very slowly throughout the course of the disease and can remain relatively stable for long periods of time or even for life, without affecting work, school, or life. Not all intracranial arachnoid cysts require surgery; asymptomatic surgery may not be necessary, and those without increased intracranial pressure and local neurological abnormalities may be held off surgery and may be followed up for observation. However, surgery is required if symptoms of compression, such as hemiparesis and vision loss, occur. The following conditions should be seen in a timely manner: 1) Regular radiographic examination to note whether the cyst is progressively enlarging. 2) The presence of cyst compression of brain tissue, producing intracranial hypertension or neurological localization signs. 3) Presence of intolerable symptoms and ineffective conservative treatment. 4) Cyst-induced epilepsy.