Glymphatic system, illustration. Also known as the glymphatic clearance pathway or the paravascular system, this system clears waste and fluid from the vertebrate central nervous system (CNS). Interstitial fluid is removed via the cerebrospinal fluid (CSF). It is similar to the lymphatic system, but functions to remove waste products from the brain and spinal cord. This view shows the subarachnoid space (across top) between the brain and its membranes. The blue arrows show the movement of interstitial fluid and solutes.