Meninges and Ventricle system Flashcards
What are the three layers of the Meninges
Dura mater, Arachnoid and pia mater
Describe the outer most layer of meninges
Dura mater
Outer layer - right under skull, surrounds entire brain
Inner layer - Connected to outer until branches off between two hemispheres of the brain.
Describe the inner most layer of meninges
Pia mater
Adheres to brain, follows gyri and extends into sulci.
describe the middle layer of meninges
Arachnoid mater
Forms the subarachnoid space which contains blood vessels and CSF
What are the Dural folds and their locations
Falx cerebri - Separates cerebral hemispheres
Falx cerebelli - Separates cerebella hemispheres.
Tentorium cerebelli - Separates cerebrum from cerebellum.
What are Venus sinus’
Where the dura mater layers separate. Collects Venus blood from brain and ‘old’ CSF once cycled through ventricular system
What do arachnoid granulations do
Perforate inner layer of dura mater and transport ‘old’ CSF from subarachnoid space into Venus sinus’
Where do veins sit
In subarachnoid space on top of pia mater.
What is the ventricle system
Network of interconnected ‘spaces’ within the brain filled with CSF
What are the ventricles and their locations
Lateral ventricle (2) - One in each hemisphere Third ventricle (1) - In diencephalon Fourth ventricle (1) - Level with cerebellum
What is the path of the CSF
From lateral ventricle to 3rd ventricle through cerebral aqueduct into 4th ventricle to the arachnoid space, flows around brain and spinal cord and out through arachnoid granulations into Venus sinus’
What does Cerebral Spinal Fluid (CSF) do
Transports nutrients and waste and helps to protect the brain and spinal cord (nourishes and protects)
How does CSF circulate
ventricles are internally lined with ependymal cells which circulate CSF with waving cilia
Where is CSF produced
By choroid plexus within ventricles
