Where does cerebral spinal fluid (CSF) come from?
The CSF is created within the ventricles, fluid-filled spaces near the center of the brain. There are two lateral ventricles, which connect to the third and fourth ventricle before emptying into the subarachnoid space. The ventricles contain a choroid plexus, a capillary network that creates CSF from blood plasma. The CSF circulates around the brain and spinal cord and is later reabsorbed into the blood by way of the arachnoid granulations near the top of the skull. CSF is secreted and absorbed in a continuous process called the CSF circulation (see illustration below).
