Meninges Flashcards
What are meninges
Several layers of tissue between skin + brain
What is the Pia Mater
- Soft connective tissue
- Anchored to CNS by astrocytes
What is the subarachnoid space
Flow to CSF
What is the Arachnoid mater
Has arachnoid granulation on superficial surface
What are the 2 layers of the dura mater
- Meningeal layer
- Periosteal layer
Describe the periosteal layer
Tough layer that clings to bone
What are the dural folds and what are their roles
Protect delicate tissue from movement:
- Falx cerebelli - Sits between 2 spheres of cerebellum
- Tentorium cerebelli - Prevents cerebellum and cerebrum from bashing
- Falx cerebri - Keeps left and right hemisphere in situ
Give the names of the layers of the meninges in order
- Pia mater
- Subarachnoid space
- Arachnoid mater
- Subdural space
- Epidural space
- Skull bone
- Scalp-skin
Describe a epidural haemorrhage
- In extra dural space, due to the meningeal layer being injured
- As it’s a bleed outside the meninges, it peels away the periostea layer of dura from the skull due to the influx of blood
- On a CT scan, it looks biconcave
Describe an subdural haemorrhage
- In subdural space, the bridging veins become torn, the blood spreads between the dura and arachnoid so on a CT scan we can see a present around the skull
Describe a subarachnoid haemorrhage
- In subarachnoid space
- A torn cerebral artery as a result of aneurysms, blood mixes with CSF
- Pia mater is close to the brain so it can invaginate into the sulci of cerebrum
Fill the gaps
Describe the dura mater of the spinal cord
- No periosteal component in spinal meninges
- Separated from bone of vertebrae by epidural space, a a real space filled with fat
Describe the arachnoid mater of the spinal cord
- Surrounds the spinal cord
- Very thin potential subdural space
Describe the Pia mater of the spinal cord
Tightly adhered to the surface of the spinal chord, between the Pia and arachnoid space containing CSF
Describe the denticulate ligaments of the spinal cord
Prevent the lateral movement of the spinal cord
What are the functions of the meninges and CSF
- Protect the CNS
- Cushion and nourish
