MENINGES

Question 1

What are the three layers of the meninges

Answer 1

Dura mater
Arachnoid mater
Pia mater

Question 2

What are the two layers of the dura mater

Answer 2

Periosteal

Meningeal

Question 3

Describe the periosteal layer

Answer 3

Seal the skull from pathogens etc. Periosteal layer has different names depending on location.
Is continuous with the periosteum on outer surface of skull at foramina

Question 4

What are the dural partitions

Answer 4

falx cerebri, tentorium cerebelli, falx cerebelli, diaphragma sellae

Question 5

What is the blood supply of the dura mater

Answer 5

The anterior, middle and posterior meningeal arteries. They run in the periosteal layer in groves in skull. Main is from middl menangial which enters through foramen spinosum, runs behind pterion suture.

Question 6

What is the innervation of the dura

Answer 6

Trigeminal nerve branches, 1, 2, 3 cervical nerves and maybe CIX and CXII

Question 7

Where do venous sinus form

Answer 7

Between periosteal and meningial layers of the dura

Question 8

Where are the cavernous sinuses found

Answer 8

Either side of the turkish saddle. The body of the sphenoid bone

Question 9

What structures run through the cavernous sinus (along wall and medially

Answer 9

Along wall: CIII, CIV, V1, V2

Internal: VI, internal carotid artery

Question 10

What are emissary veins

Answer 10

Run from external skull to internal sinus.

Question 11

What are diploic veins

Answer 11

Drain from within bone to sinuses

Question 12

What are cerebral veins

Answer 12

Drain from brain to sinuses.

Question 13

Describe the arachnoid mater

Answer 13

Avascular membrane, does not enter grooves or fissures (except the longitudnal fissure), roof of subarachnoid space.

Question 14

What is the purpose of arachnoid granulations

Answer 14

Drain CSF to sinuses

Question 15

Describe the pia mater

Answer 15

Invests the surface of the brain. Firmly adherent.

Question 16

If meningeal artery is damaged what kind of bleeding would you get

Answer 16

Extradural haemorrhage. Between periosteal layer and calvarium.

Question 17

What causes extradural haemorrhage

Answer 17

Almost always arterial origin, usually at pterion, middle meningeal artery.

Question 18

Where does a subdural haemorrhage occur

Answer 18

Within the meningeal layer, i.e. the meningeal layer kind of splits.

Question 19

What causes subdural haemorrhage

Answer 19

Usually venous origin. Often in elderly as a result of cerebral atrophy

Question 20

What is the origin of subarachnoid haemorrhage

Answer 20

Usually cerebral artery from a ruptured cerebral aneurysm of the circle of willis

Question 21

What are the three forms of intracranial haemorrhage

Answer 21

Subdural, extra dural, subarachnoid

Question 22

Describe the middle menangial artery

Answer 22

Branches from the Maxillary, enters skull via pterygopalatine fossa and foramen spiniosum (posterio part of greater wing of sphenoid), supplies dura mater and meninges. At risk of rupture in skull fracture around the pterion causing extradural haemorhage

Question 23

What supplies innervation of the dura

Answer 23

Trigeminal

Question 24

Where do venous sinuses form

Answer 24

Between the periosteal and meningeal layers of the dura

Question 25

What sinus becomes the internal jugular vein

Answer 25

Sigmoid sinus

Question 26

What is found in the cavernous sinus

Answer 26

Internal carotid and abducent nerve medial

Lateral walls Trochlear, occulomotor, V1 and V2

Question 27

Where is the cavernous sinus

Answer 27

Either side of the sella turcica

Question 28

What do the opthalmic veins drain to

Answer 28

Cavernous sinus

Question 29

If a patient has periorbital cellulitis what is the risk

Answer 29

Cavernous sinus thrombosis

Question 30

What causes raccoon eyes

Answer 30

Skull fracture, blood leaks from skull into potential space in eelids via a tear in the periosteum layer of meninges

Question 31

What are emissiary veins

Answer 31

Run between outside of the skull to the sinuses

Question 32

What is a diploic vein

Answer 32

Vein within skull draining to skull bone

Question 33

Difference between dura in skull and spine

Answer 33

2 layers in skull- periosteal and meninges. 1 layer in spine meningeal

Question 34

Is the arachnoid mater vascular or avascular

Answer 34

Avascular

Question 35

What drains CSF to sinus

Answer 35

Arachnoid granulation

Question 36

What layer are the meningeal arteries found

Answer 36

Between the periosteal layer and the dura of the skull

Question 37

What layer are the cerebral arteries found

Answer 37

Subarachnoid space

Question 38

What layers do the cerebral veins need to cross to drain in to sinus

Answer 38

Arachnoid mater and meningeal layer of the dura

Question 39

If meningeal artery damaged what kind of haemmorhage ensues

Answer 39

Extradural

Question 40

What layer is a subdural haemmorhage

Answer 40

Within the meningeal layer of the dura

Question 41

In the subdural haemmorhage what is the usual cause

Answer 41

Venous damage from cerebral veins in elderly

Question 42

What is usual origin of subarachnoid haemmorhage

Answer 42

Cerebral arteries- can be veins

Question 43

What is the surface anatomy of the pterion

Answer 43

2.6cm posterio and 1.3cm above the posterolateral birder of the frontozygomatic suture

Question 44

What is the thinnest part of the skull

Answer 44

Squamous part of temporal bone