CSF And Cerebral Blood Flow

Question 1

What is the meninges

Answer 1

The membranous coverings of brain and spinal cord

Question 2

What are the 3 layers of the meninges

Answer 2

Dura mater
Arachnoid mater
Pia mater

Question 3

What are the 2 major functions of the meninges

Answer 3

Supportive framework for cerebral and cranial vasculature
Acting with CSF to protect CNS from mechanical damage

Question 4

What is the dura mater

Answer 4

The outermost layer of meninges directly underneath bones of skull and vertebral column

Question 5

What are the 2 layered sheets of connective tissue in the dura mater

Answer 5

Periosteal layer
Meningeal layer

Question 6

What is the periosteal layer

Answer 6

Lines inner surface of bones of cranium

Question 7

What is the meningeal layer

Answer 7

Located deep to periosteal layer
Continuous with dura mater of spinal cord

Question 8

What is located between the 2 layers of dura mater

Answer 8

Dural venous sinuses

Question 9

What is dura mater innervated by

Answer 9

CNV (trigeminal)

Question 10

Where does the dura mater receive its vascular supply from

Answer 10

Middle meningeal artery and vein

Question 11

What is the dural venous sinuses responsible for

Answer 11

Venous drainage of cranium and empty into internal jugular veins

Question 12

What are the 4 dural partitions

Answer 12

Falx cerebri
Tentorium cerebelli
Falx cerebelli
Diaphragma sellae

Question 13

What does the falx cerebri do

Answer 13

Projects downwards to separate right and left cerebral hemispheres

Question 14

What does the tentorium cerebelli do

Answer 14

Separates occipital lobes from cerebellum contains space for passage of brain - tentorial notch

Question 15

What does the falx cerebelli do

Answer 15

Separates right and left cerebella hemispheres

Question 16

What does the diaphragma sellae do

Answer 16

Covers hypophysial fossa of sphenoid bone contains small opening for passage of stalk of pituitary gland

Question 17

What is the arachnoid mater

Answer 17

Middle layer of meninges lying directly underneath dura mater

Question 18

What is underneath arachnoid mater

Answer 18

Space which is known as sub arachnoid space which contains CSF acting as a cushion for the brain

Question 19

What does arachnoid mater consist of

Answer 19

Layers of connective tissue it is avascular and does not receive any innervation

Question 20

What are arachnoid granulations

Answer 20

Small projections of arachnoid mater into dura allowing CSF to re enter circulation via dural venous sinuses

Question 21

Where is pia mater located

Answer 21

Underneath sub arachnoid space

Question 22

How does the pia mater appear

Answer 22

Very thin tightly adhered to surface of brain and spinal cord
Highly vascularised with blood vessels perforating through membrane

Question 23

How many dural venous sinuses are there

Answer 23

11 in total

Question 24

Where is the straight, superior and inferior sagittal sinuses found

Answer 24

In falx cerebri of dura mater

Question 25

Which sinus is a continuation of the great cerebral vein and inferior sagittal sinus

Answer 25

Straight sinus

Question 26

What does the cavernous sinus do

Answer 26

Drains ophthalmic veins and can be found on either side of sella turcica

Question 27

How does blood return to the internal jugular vein

Answer 27

Via superior or inferior petrosal sinuses

Question 28

What are the 6 structures that the cavernous sinus receives venous drainage from

Answer 28

Facial veins Ophthalmic veins Superficial middle cerebral vein Sphenoparietal sinus Central vein of retina Pterygoid plexus

Question 29

What 3 structures travel through lateral wall of cavernous sinus

Answer 29

Oculomotor nerve Trochlear nerve Ophthalmic and maxillary branches of trigeminal nerve

Question 30

What 3 structures travel through the cavernous sinus

Answer 30

Abducens nerve Carotid plexus (post ganglionic sympathetic nerve fibres) Internal carotid artery (cavernous portion)

Question 31

What nerve is most commonly affected by cavernous sinus thrombosis

Answer 31

Abducens nerve

Question 32

What secretes CSF

Answer 32

Choroid plexus found in roof of ventricles derived from blood plasma but lower in protein

Question 33

What are the 5 functions of the CSF

Answer 33

Protection Buoyancy Chemical stability Homeostasis Cleaning waste

Question 34

Which has a higher protein content CSF or blood

Answer 34

Blood

Question 35

What is the ventricular system

Answer 35

Structures that produce CSF and transport it around the cranial cavity

Question 36

What is the ventricular system lined with

Answer 36

Ependymal cells which form choroid plexus

Question 37

What are the 4 ventricles in the ventricular system

Answer 37

Right and left lateral ventricles Third and fourth ventricles

Question 38

What is the foramen of monro

Answer 38

Where the lateral ventricles connect to the third ventricle

Question 39

What are the 2 protrusions on the anterior surface of the third ventricle

Answer 39

Supra optic recess Infundibular recess

Question 40

What are the 2 places that the fourth ventricle drains into

Answer 40

Central spinal cord Subarachnoid cisterns

Question 41

What does the choroid plexus consist of

Answer 41

Capillaries and loose connective tissue surrounded by cuboidal epithelial cells

Question 42

How is plasma filtered from blood

Answer 42

By epithelial cells to produce CSF

Question 43

What are zonula occludens

Answer 43

Provide structural support to endothelial wall, circumscribe cells and provide seal with all adjacent cells

Question 44

What are zonula adherens

Answer 44

Connects adjacent cells

Question 45

What are astrocytes

Answer 45

Highly branched cells with small bodies found both in white and grey matter

Question 46

What are the 2 paired arteries responsible for the blood supply to the brain

Answer 46

Vertebral Internal carotid arteries

Question 47

What is the circle of Willis

Answer 47

The terminal branches of the arterial supply to the brain form an anastomotic circle

Question 48

Where do the internal carotid arteries originate from

Answer 48

At bifurcation of left and right common carotid arteries at level of 4th cervical vertebrae

Question 49

Where do the right and left vertebral arteries arise from

Answer 49

Subclavian arteries, medial to anterior scalene muscle

Question 50

What are the 3 main constituents of the circle of Willis

Answer 50

Anterior cerebral arteries Internal carotid arteries Posterior cerebral arteries