Meninges and spinal cord

Question 1

Name the meninges

Answer 1

Dura mater, arachnoid mater, pia mater

Question 2

Describe the dura mater in the skull

Answer 2

2 layers, endosteal is similar to the periosteum, inner meningeal layer
Usually fused but sometimes separate to form sinuses for venous blood drainage

Question 3

Describe the dura mater in the spinal cord

Answer 3

Continuous with meningeal dura, separated from the periosteum of spinal vertebrae by loose fatty CT that contains the internal vertebral venous plexus

Question 4

What is the falx cerebri?

Answer 4

Fold of dura in the mid saggital plane between the 2 hemispheres

Question 5

What is the tentorum cerebelli?

Answer 5

Dura that covers the cerebellum and supports occipital lobes. Attached to petrous temporal bone and occipital bone

Question 6

What is the falx cerebelli?

Answer 6

Small vertical fold of dura between two cerebellum hemispheres (attaches to occipital bone and tentorum cerebelli)

Question 7

What happens to the dura when cranial nerves leave the skull?

Answer 7

Blends with epineurium

Question 8

What is the blood supply to the dura?

Answer 8

meningeal arteries

Middle meningeal artery lies between meningeal and endosteal layers of dura

Question 9

What is in the subarachnoid space?

Answer 9

CSF and cerebral vessels, cranial nerves also pass through

Question 10

What are arachnoid granulations?

Answer 10

Protrusions of arachnoid mater that provide a route for CSF to return to blood, found in venous sinuses (esp. superior sagittal sinus)

Question 11

Describe the pia mater

Answer 11

Closely invests in the brain and accompanies cerebral arteries into the substance of the brain

Question 12

What is a cistern? Name 3 examples

Answer 12

An enlargement of subarachnoid space

E.g. interpenduncular, cerbromedullary and pontine

Question 13

What happens if there is a rupture of an aneurysm of the circle of willis?

Answer 13

Subarachnoid haemorrhage

Thunderclap headache at back of head

Question 14

What happens if there is a tearing of the veins in the brain?

Answer 14

Subdural haemorrhage
Occurs in very young and very old due to smaller brains
Slower and self limiting as bleeds into venous sinuses

Question 15

What happens if there is a minor blow to the head at the pterion?

Answer 15

Middle meningeal vessel damage

Extradural haemorrhage

Question 16

Where is a lumbar puncture taken and why?

Answer 16

Subarachnoid space (containing CSF) extends to S2 whereas spinal cord terminates at L1 so L2-L4 is safe

Question 17

What is the ligamentum denticulatum?

Answer 17

Attaches pia mater to dura and arachnoid mater so the spinal cord is suspended in the dural sheath

Question 18

What is the blood supply of the spinal cord?

Answer 18

Anterior spinal artery and 2 posterior spinal arteries (from vertebral arteries)
Reinforced by segmental arteries from intervertebral foramina
All that enter spinal medulla are end arteries

Question 19

What is the venous drainage of the spinal cord?

Answer 19

Drain into totuous longitudinal channels that communicate with the venous sinuses of the skull and with the internal vertebral venous plexus