The total amount of cerebrospinal fluid in adults is about 110-200 mL, with an average of about 130 mL and a daily production of about 500 mL.1. Adult cerebrospinal fluid is mainly produced in the choroid plexus of the lateral ventricles, with a small percentage originating in the 3rd and 4th ventricles. Generally, cerebrospinal fluid passes through the interventricular foramen to the third ventricle, then through the middle cerebral aqueduct to the fourth ventricle, and then through the middle and lateral foramina to the brain and subarachnoid space.2 However, there are some diseases that can affect the secretion of cerebrospinal fluid, such as acute or chronic intracranial inflammation, peak cerebral edema, or choroid plexus papilloma, the secretion of cerebrospinal fluid can increase significantly, reaching 5,000-6,000 mL per day. 6000mL or so, so the amount of cerebrospinal fluid in adults is usually around 130mL.