Cerebrospinal fluid is a clear, colorless liquid that exists in the ventricles and subarachnoid space and has a variety of functions for the brain and spinal cord, including protective support and nutrition. The main site of cerebrospinal fluid production is the lateral ventricular choroid plexus, which accounts for about 95% of the cerebrospinal fluid, with the rest originating from the third and fourth ventricles, among other sites. Cerebrospinal fluid flows through the interventricular foramen, into the third ventricle, the midbrain aqueduct, the fourth ventricle, and finally, through the middle foramen of the fourth ventricle and two lateral foramina, to the surface of the brain and spinal cord, to the subarachnoid space and the brain pool. Most of the cerebrospinal fluid is absorbed through the arachnoid granules on the surface of the cerebral vault, absorbed into the superior sagittal sinus, and a small portion is absorbed through the interstitial space of the spinal nerve roots. The total amount of cerebrospinal fluid in adults is 110-200 mL, with an average of 130 mL. It is produced at a rate of 0.3-0.5 mL per minute, generating 400-500 mL per day.