The Flow of Cerebrospinal Fluid

Step 8

At arachnoid villi, CSF is reabsorbed into venous blood of dural venous sinuses.

Step 7

CSF fills subarachnoid space and bathes external surfaces of brain and spinal cord.

Step 4

CSF flows down cerebral aqueduct to fourth ventricle.

Step 6

CSF flows out two lateral apertures and one median aperture.

Step 2

CSF flows through interventricular foramina into third ventricle.

Step 1

CSF is secreted by choroid plexus in each lateral ventricle.

Step 5

Choroid plexus in fourth ventricle adds more CSF.

Step 3

Choroid plexus in third ventricle adds more CSF.