Meninges

Question 1

How is spinal epidural space different to epidural space of the brain?

Answer 1

The space is real in spinal cord but only a potential space in the brain.

Question 2

Where does the pia mater end?

Answer 2

At the level of L1/2 at the conus medullaris

Question 3

What is the filum terminalis?

Answer 3

Pia mater extends from the end of the conus medullaris to the coccyx to anchor the spinal cord.

Question 4

What are denticulate ligmanets?

Answer 4

Also known as trabeculae and are projections of pia mater that anchor the spinal cord to the dura (projects through the arachnoid which is why it looks the way it does)

Question 5

What are subarachnoid cisterns?

Answer 5

Dilated subarachnoid spaces located where pia mater is not present but dura and arachnoid mater are present..

Question 6

What are arachnoid granulation/

Answer 6

Extensions of pia mater at the top of the cerebrum into dural sinus.

Question 7

What is the function of arachnoid granulations?

Answer 7

They project into superior sagittal sinuses and provide an avenue for one-way CSF flow into venous blood (i.e they drain the CSF)

Question 8

Does the dura mater get sensory nerve supply?

Answer 8

Only the periosteal layer does

Question 9

What are the layers of the dura mater?

Answer 9

Periosteal layer (adheres to periosteum of the skull)

Meningeal layer divides cranial cavity into compartments

Question 10

What does the periosteal layer of dura do?

Answer 10

Adheres to periosteum of the skull.

Question 11

What are the important functions of the meningeal layer?

Answer 11

Forms dural reflections preventing excess movement of brain within cranial cavity.

The folds anchor the brain and prevent excess movement

The folds carry veins in what are called dural venous sinuses which drain CSF

Question 12

What nerves carry sensory innervation to dura?

Answer 12

Vagus

Trigeminal

3 cervical nerves

Question 13

What are the meningeal reflections that are important for formation of compartments in the brain?

Answer 13

Falx cerebri

tentorium cerebelli

Falx cerebelli

Diaphragm sellae

Question 14

Where does the falx cerebri start?

Answer 14

At the crysta gali (cribiform plate) anteriorly and the tenrorium cerebelli posteriorly

Question 15

What does the tentorium cerebelli divide the brain into?

Answer 15

Supratentorial and infratentorial cavities

Question 16

What are the attachments of the tentorium cerebelli?

Answer 16

Anterior: Free border forms tentorial notch which attaches to the anterior clinoid process.

Posterior: Petrous part of temporal bone, occipital bone

Superior attachment: Falx cerebri

Inferior attachment: Falx cerebelli

Question 17

What is the falx cerebelli?

Answer 17

Continuation of the falx cerebri which forms a membrane that goes between the 2 hemispheres of cerebellum.

Question 18

What are the attachments of the falx cerebelli?

Answer 18

Anterior: Free border partially separating cerebellar hemispheres

Posterior Occipital bone

Superior: Tentorium cerebelli

Inferior: Posterior foramen magnum

Question 19

What is the function of the diaphragm sellae?

Answer 19

Cover the sella turcica and forms the root of the pituitary fossa.

Allows passage of infundibulum

Question 20

What are the attachments of the diaphragm sellae?

Answer 20

Anterior: Tuberculum sellae

Posterior: Dorsum sellae, posterior clinoid process.

Question 21

Sinuses are easier to learn by looking at diagram on the slides.

Answer 21

All we really need to know is that they all drain into the internal jugular.