the ventricular system

Question 1

What are ventricles in the brain

Answer 1

Series of CSF-filled interconnected spaces, continuous with the subarachnoid space and central canal.

Question 2

How do the ventricles appear in an MRI

Answer 2

ventricles appear black

Question 3

what structures surround the lateral ventricles

Answer 3

the septum pellucidum and the corpus callosum sits in the roof.
The caudate nucleus sits in the lateral walls and the hippocampus sits in the floor of the inferior horn

Question 4

How do the lateral ventricles communicate

Answer 4

They communicate with the third ventricle through the interventricular foramen also called the foramen of monro

Question 5

Outline the 3rd ventricles

Answer 5

appears as a slit-like cleft, thalami sit in lateral walls and fornix sits in the roof.

Question 6

How does the 3rd ventricle communicate with the 4th

Answer 6

communicate via the cerebral aqueducts which is surrounded by midbrain

Question 7

What surrounds the 4th ventricle

Answer 7

surrounded by hindbrain, cerebellum posterior, pons and medulla anterior, cerebellar peduncles lateral.

Question 8

How does the 4th ventricle communicate with the subarachnoid space

Answer 8

3 foramina exit into the subarachnoid space, two foramen of luschka (lateral) and one foramen of magendie (middle).

Question 9

How is cerebral spinal fluid produced

Answer 9

produced by choroid plexus and it is present throughout ventricles.

Question 10

Outline the structure of choroid plexus

Answer 10

capillary network surrounded by cuboidal epithelium, blood filtered through cap fenestrations and components transported through cuboidal epithelium into ventricles, tight junction between cuboidal epithelium forms the blood csf barrier as it prevents macromolecules from entering.

Question 11

outline structure of cuboidal epithelium

Answer 11

villi to increase SA, active transport csf components, bidirectional, not all csf produced by choroid plexus within ventricles.

Question 12

How does CSF flow within the ventricles

Answer 12

goes from lateral ventricle to third via interventricular foramen to fourth via cerebral aqueduct to cisterna magna via foramina of luschka and magendie.

Question 13

outline the importance of CSF in subarachnoid space

Answer 13

CSF alway in contact with the brain parenchyma which is important for the transfer of micronutrients into the brain and removal of metabolites.

Question 14

outline absorption of CSF

Answer 14

CSF pressure in subarachnoid space exceeds pressure in venous sinuses, prevents blood pooling in subarachnoid space.

Question 15

How much CSF is made per day

Answer 15

around 500ml of CSF per day

Question 16

What are the functions of CSF

Answer 16

hydraulic buffer to cushion brain against trauma, vehicle for removal of metabolites from CNS,
stable ionic environment for neural function and transport of neurotransmiters and chemicals.

Question 17

What are the colours of CSF in disease

Answer 17

yellow or pink shade in subarachnoid haemorrhage

cloudy or turbid in bacterial meningitis due to wbc

Question 18

How is CSF sampled

Answer 18

Taken by lumbar puncture at lumbar cistern, L4/5 for kids and L3/4 for adults.

Question 19

What is hydrocephalus

Answer 19

dilation of the ventricles due to blocked CSF circulations which may be due to impaired absorption or over secretion. increased intracranial pressure on surrounding tissue affects neurological function

Question 20

Symptoms of hydrocephalus

Answer 20

headaches, vomiting, visual disturbances, papilledema, seizures, altered cognition, balance and coordination problems. may be congenital or acquired

Question 21

What are the 2 types of hydrocephalus

Answer 21

communicating and non communicating,

Question 22

Outline non-communicating hydrocephalus

Answer 22

blockage within ventricular system due to tumour, cyst, stenosis.
CSF does not circulate over surface of brain, surgery: insert shunt to reduce intracranial pressure.

Question 23

What is daddy walker syndrome (form of non-com hydrocephalus)

Answer 23

congenital malformation of the cerebellum, obs within foramina of 4th ventricle, dilation of lateral, third and 4th ventricle (symmetrical). child head may be large

Question 24

Outline communicating hydrocephalus

Answer 24

CSF can pass through ventricular system, enter subarachnoid space but cannot enter venous sinuses, can be due to trauma, subarachnoid haemmorhage or bac meningitis.