Neurology Anatomy- Csf, Meninges And Ventricles

Front 1

Name the structures

Back 1

Front 2

Name the structures

Back 2

Front 3

Name the structures

Back 3

Front 4

What is the percentage of epidural hematoma that is from a venous origin?

Back 4

10%

Front 5

When do you typically see an epidural hematoma?

Back 5

blows to the side of the head that ruptures a middle meningeal artery

Front 6

Most bleeds into the subarachnoid space are from?

Back 6

aneurysms from the Circle of Willis

Front 7

How would a stroke occur after a subarachnoid haemorrhage?

Back 7

blood in the subarachnoid space mixes with the CSF and coats the pia. RBCs then die and release their contents which are vasoconstrictive and decrease arterial diameter which may lead to a stroke

Front 8

Via which foramina does the 3rd ventricle communicate with the lateral ventricles

Back 8

Foramina Munro

Front 9

What is the name of the aqueduct that transverses the midbrain?

Back 9

Mesencephalic (cerebral) aquaduct

Front 10

Describe the structures around the 4th ventricle

Back 10

Sandwiched between: cerebellum, pons and rostral medulla.

It's floor = rhomboid fossa

It's roof = superior and inferior medullary vela of the cerebellum

Front 11

What are the three apertures in the 4th ventricle?

Back 11

foramen of Magendie
foramina of Luschka

Front 12

How does CSF differ from blood?

Back 12

High in: Na, Mg

Little in: K, Ca

Low in: Cells and protein

Remains stable

Front 13

Where is CSF made?

Back 13

Choriod plexus (80%) and ependyma cells (line ventricles)

Front 14

Where is the choriod plexus not found?

Back 14

anterior and posterior horns of the lateral ventricles

Note: important for catheters or measuring pressure. Choriod plexus clogs catheter tip

Front 15

How much CSF is made per day?

Back 15

500ml

Front 16

How many times is CSF replaced in a day?

Back 16

4 times

Front 17

Which Cistern contains he Circle of Willis?

Back 17

Interpeduncular Cistern

Front 18

Which Cistern is of radiological improtance and why?

Back 18

Superior Cistern

Contains:
1. great cerebral vein of Galen
2. pineal gland
3. continues rostrally into transverse fissure

Front 19

True of False:

When the pressure is high in the Subarachnoid space, it follows down it's concentration gradient into the dorsal venous sinuses (e.g. Superior Sagittal Sinus) and when the pressure is high in the sinuses, CSF flows back down its concentration gradient into the subarachonoid space

Back 19

False

The flow is unidirectional, due to valves in the arachnoid villi

Front 20

Where are the three main blood-brain-barriers?

Back 20

1. Arachnoid
2. Choroid Plexus
3. Cerebral Capillaries

Front 21

How does the arachnoid act as a BBB?

Back 21

Passive functions

1. ependymal cells fold over themselves
2. tight junctions
3. impermeable to hydrophilic substances

Front 22

How does the Choroid Plexus act as a BBB?

Back 22

Selectively permeable -prevent most macromolecules from entering CSF

1. Microvilli on CSF side -allows CSF out
2. Tight junctions -keep most things from getting in

More permeable than the other BBBs

Front 23

How does the Cerebral Capillaries act as a BBB?

Back 23

1. Non fenestrated
2. Tight Junctions of endothelial cells

Front 24

When might the BBB break down?

Back 24

1. infection
2. Trauma
3. Stroke
4. Tumour

Front 25

What type of Spina Bifida does the following features describe?

Defect in the lumbosacral region, where the SC, spinal roots and meningitis protrude into a sac/cysts and there is constant leakage of CSF

Back 25

Spina bifida cystica -myelomeningocele

Front 26

When does myelomeningocele usually occur in gestation and what is it due to?

Back 26

Usually 4th week of gestation

Due to failure of posterior neuropore closure

Front 27

When should folate supplement be given to a woman preparing to have a child and why?

Back 27

before 3-4 weeks of gestation (before neural tube is programmed to close)

Reduces the risk of myelomeningocele by 80%

Front 28

What are the reasons for a child born with myelomeningocele developing hydrocephalus?

Back 28

1. abnormal part of the SC tethering to the vertebral column. Which pulls the medulla into the foramen magnum

2. CSF is escaping through the opened neural tube, however after surgery, hydrocephalus can occur due to the above mentioned reason

Front 29

At what level does spina bifida occult usually occur?

Back 29

the arch of a single vertebra is opened usually either at LV5 or SV1

Front 30

When does spina bifida occult occur during gestation and why?

Back 30

Occurs: 5-12 weeks of gestation

Why: failure of the vertebral precursor cells to migrate around the SC

Front 31

True or False

Spina Bifida Occulta isn't associated with any clinical features because the SC is normal?

Back 31

True

Only a defect of the vertebral column which is often marked hy a tuft of hair, pigmented nevus or a dimple

Front 32

What is the only difference between Spina Bifida Occulta and Spina Bifida Cystica -meningocele?

Back 32

Several vertebrae are involved in meningocele.

Meningocele is rare malformation

Front 33

What is a common herniation?

Back 33

Herniation across the temporal lobe/over tentorium cerebelli

Causes:
1. paresis of IIIn
2. contralateral UMN symptoms (due to compression of cerebral peduncle against tentorium)

Front 34

What type of herniation is life threatening and why?

Back 34

Tonsillar herniation

because it compresses vital centres in the BS --> coma