-
[♪ Music ♪]
-
Hello.
-
Today we’re going to talk about
cerebrospinal fluid
-
and its flow through the ventricles
and the sub-arachnoid spaces
-
in the brain and spinal cord.
-
CSF is the fluid which supplies
nutrients to the cortex
-
and to deeper structures
within the brain
-
rather than the blood flow,
which supplies nutrients
-
to the surface regions.
-
It is produced in the CHOROID PLEXUS,
shown here in red;
-
which covers the floor
of the LATERAL VENTRICLE,
-
and the roof of the THIRD VENTRICLE.
-
The CSF flows from the choroid plexus
through the body and tail
-
of the lateral ventricle;
and into the third ventricle
-
via the INTERVENTRICULAR FORAMEN.
-
CSF then flows to the 4th VENTRICLE
via the CEREBRAL AQUEDUCT,
-
exiting via the MEDIAL
and LATERAL apertures.
-
CSF exiting from the lateral apertures
flows to the PONTINE CISTERN
-
on the ventral surface of the brain stem;
while flow from the medial aperture
-
enters the CEREBELLO-MEDULLARY cistern.
-
It then follows one of two paths.
-
The first flows round the CEREBELLUM,
draining into the SUPERIOR CISTERN
-
from where it flows into
the INTERPEDUNCULAR CISTERN.
-
The second path flows down
the sub-dural space
-
surrounding the spinal cord
to the LUMBAR CISTERN.
-
This is where fluid is taken from
in a LUMBAR PUNCTURE.
-
CSF then flows back up the spinal cord
and it joins flows from the 4th ventricle
-
and the superior cistern.
-
From the ventral cisterns,
CSF flows across the cortical surfaces
-
in the sub-arachnoid space
draining into the SUPERIOR SAGITTAL SINUS
-
via the ARACHNOID GRANULATIONS.
-
It the flows down the posterior surface
towards what is called
-
the CONFLUENCE OF THE SINUSES
where it joins the venous blood
-
flowing from sub-cortical regions
via the STRAIGHT SINUS.
-
[♪ Music ♪]