L.5

Question 1

What makes up the ventricular system

Answer 1

• 2 lateral ventricles
• the 3rd ventricle
• the 4th ventricle

Question 2

Where are the lateral ventricles located

Answer 2

cerebral hemispheres

Question 3

What are the 4 main structures of lateral structures

Answer 3

• anterior horn
• posterior horn
• inferior horn
• body

Question 4

What is the function of the septum pellucidum

Answer 4

separates lateral ventricles from each other

Question 5

What is the function of corpus callosum

Answer 5

forms rood of ventricles

Question 6

Where is the caudate nucleus located

Answer 6

forms the lateral wall of the ventricle

Question 7

Where is the hippocampus located

Answer 7

lies on floor of the inferior horn

Question 8

What is the function of the foramen of monro

Answer 8

communication between lateral ventricles and 3rd ventricles

Question 9

Where is the third ventricle located

Answer 9

it is in between the thalamus and hypothalamus

Question 10

What is the function of the cerebral aqueduct

Answer 10

it connects the 3rd and 4th ventricle

Question 11

Where is the 4th ventricle located

Answer 11

between the pons/medulla and cerebellum

Question 12

What is the function of the 4th ventricle

Answer 12

it is continuous with the central canal of spinal cord and allows CSF to flow down to spinal cord

Question 13

What are 2 structures part of 4th ventricle

Answer 13

• foramina of Luschka
• foramen of Magendie

Question 14

What is the function of the foramina of Luschka

Answer 14

2 lateral openings that allow CSF to exit into the subarachnoid space

Question 15

What is the function of the foramen of Magendie

Answer 15

a single midline opening that allow CSF to flow into the subarachnoid space (cisterna magna)

Question 16

Why are these foramina important

Answer 16

• they maintain the flow of CSF
• they prevent a buildup of CSF in the brain

Question 17

What are the functions of the CSF

Answer 17

• cushions brain against trauma
• removal metabolites (metabolic waste) from CNS
• transport NTs and chemicals
• stable ionic environment for neuronal function

Question 18

Where is the choroid plexus located

Answer 18

they are located in each ventricle of the brain

Question 19

What are the function of choroid plexus

Answer 19

produces CSF

Question 20

How is CSF produced

Answer 20

choroid plexus filters blood from internal carotid and basilar arteries to produce CSF

Question 21

What is the structure of the choroid plexus

Answer 21

it has fenestrated capillaries surrounded by cuboidal epithelium for blood filtration

Question 22

What is the blood CSF barrier

Answer 22

• tight junctions between epithelial cells
• prevent macromolecules from CSF
• permeable to water and CO2

Question 23

What are the features of cuboidal epithelium

Answer 23

• microvilli = increase SA
• bidirectional transport
• specialised ependymal
• active transport or facilitated diffusion

Question 24

Why is a stable ionic environment important for CSF

Answer 24

good for neuronal function

Question 25

Outline the CSF circulation

Answer 25

1. lateral ventricles --> interventricular foramen --> 3rd ventricle 2. 3rd ventricle --> cerebral aqueduct --> 4th ventricle 3. 4th ventricle --> Luschka and Magendie foramina --> subarachnoid space (cisterna magna)

Question 26

Where does the CSF flow from and into

Answer 26

CSF flows from ventricles to the subarachnoid space

Question 27

Where is the subarachnoid space located

Answer 27

located between the pia and arachnoid mater

Question 28

What is the function of the subarachnoid space

Answer 28

transfer electrolytes into brain and removal of metabolites

Question 29

What are arachnoid granulations

Answer 29

herniations of arachnoid membrane that allow CSF to drain from subarachnoid space into the venous sinuses

Question 30

What is the function of arachnoid granulations

Answer 30

removal of excess CSF and metabolites

Question 31

What happens if CSF pressure > venous pressure

Answer 31

1. arachnoid granulation open 2. allows CSF to flow into venous sinuses 3. prevents blood pooling in subarachnoid space

Question 32

What happens if venous pressure > CSF pressure

Answer 32

1. arachnoid granulations close off 2. stops CSF from flowing into the venous system 3. prevents loss of too much CSF and maintains balance

Question 33

What is the normal colour of CSF

Answer 33

clear

Question 34

What does a yellow/pink colour of CSF mean

Answer 34

bleed into subarachnoid space (subarachnoid haemorrhage)

Question 35

What does cloudy CSF mean

Answer 35

infection: cells and protein within CSF

Question 36

Why is lumbar puncture performed at lower level in children

Answer 36

the spinal cord ends lower in children due to ongoing skeletal growth

Question 37

At which vertebral levels is a lumbar puncture usually performed

Answer 37

L4/L5

Question 38

What is hydrocephalus

Answer 38

the dilation of brain ventricles

Question 39

What are the main causes of hydrocephalus

Answer 39

- blocked CSF circulation - impaired absorption - over-secretion CSF

Question 40

What is the overall effect of hydrocephalus

Answer 40

increased intracranial pressure

Question 41

What is the cause of non-communicating hydrocephalus

Answer 41

blockage within the ventricular system by a tumour or cyst

Question 42

What is the effect of non-communicating hydrocephalus

Answer 42

CSF can't reach the arachnoid space

Question 43

In non-communicating hydrocephalus, which ventricles appear dilated

Answer 43

3rd ventricle but 4th ventricle would appear normal

Question 44

What is Danfy-Walker syndrome

Answer 44

- obstruction within foramina od 4th ventricle - dilation of latera, 3rd & 4th ventricle

Question 45

What is the cause of communicating hydrocephalus

Answer 45

obstruction in the arachnoid villi

Question 46

What is the effect of communicating hydrocephalus

Answer 46

movement of CSF into venous sinuses is impeded (impaired absorption)