3. Meningeal Layers, Dural Folds And Dural Venous Sinuses

Question 1

What are the 3 membranous layers that surround and protect the brain and spinal cord?

Answer 1

Pia mater
Arachnoid mater
Dura mater

Question 2

Where is the pia mater?

Answer 2

Stuck to brain surface, unable to separate it from the brain

Question 3

What is the space between the arachnoid and pia mater nd what does it contain?

Answer 3

Subarachnoid space

Contains cerebrospinal fluid and cerebral arteries, cerebral veins

Question 4

What are the leptomeninges?

Answer 4

Pia mater and arachnoid mater

Question 5

Is there space between the dura and arachnoid mater?

Answer 5

No it is a potential space - subdural space

Question 6

Describe the 3 layers of the meninges

Answer 6

Dura -tough, fibrous membrane
Arachnoid - soft, fibrous translucent membrane
Pia - microscopically thin, delicate adherent to surface of brain, follows every fold

Question 7

What does the dura fuse with?

Answer 7

Periosteum lining inner table of skull bones

Question 8

What are the 2 layers of the dura while within the skull?

Answer 8

Periosteal - part against inner table of bone

Meningeal - part adjacent to arachnoid

Question 9

What is the extension of dura formed from meningeal layer in the vertical plane called?

Answer 9

Falx cerebri

Question 10

What is the extension of dura formed from the meningeal layer in the horizontal plane?

Answer 10

Tentorium cerebelli

Question 11

Why do we have dural folds?

Answer 11

Help to stabilise the brain and act as rigid dividers

Question 12

What happens to the brain with a rise in pressure due to the dural folds?

Answer 12

Can lead to compression and displacement of parts of brain against rigid dural folds and/or through foramen magnum

Question 13

The opening within the tentorium cerebelli which allows passage of the brainstem is called what?

Answer 13

Tentorial notch

Question 14

What are dural venous sinuses?

Answer 14

Venous blood filled spaces created by separation of meningeal from periosteal layer of dura

Question 15

Where do dural venous sinuses drain into?

Answer 15

Internal jugular vein

Question 16

What do bridging veins traverse?

Answer 16

Subdural space

Question 17

Where do bridging veins go to and from?

Answer 17

From cerebral vein in subarachnoid space to dural venous sinus

Question 18

What is the role of emissary veins?

Answer 18

Traverse through skull to connect scalp veins with dural venous sinuses

Question 19

What is bleeding within the brain tissue itself called?

Answer 19

Intracerebral haemorrhage

Question 20

Where does the middle meningeal artery run?

Answer 20

Periosteal dura and inner table of bone

Question 21

Where does the blood come from in a subdural haemorrhage?

Answer 21

Venous bleed usually from bridging veins

Question 22

Where does the blood come from in a subarachnoid haemorrhage?

Answer 22

Arterial bleed - usually from a branch of ‘Circle of Willis’

Mixes with CSF

Question 23

What causes a subarachnoid haemorrhage?

Answer 23

Secondary to trauma or spontaneous rupture of blood vessel