14: Ventricular System, SC, Damage To Brain

Question 1

What causes epidural vs subdural hematoma?

Answer 1

Epidural: middle meningeal rupture
Subdural: cerebral bridging veins rupture

Question 2

What happens in the brain during an epidural hematoma?

Answer 2

Midline shift of cerebral hemispheres -> falx and/or uncal herniations

Question 3

S/S epidural hematoma vs subdural

Answer 3

Epidural: initial unconsciousness with rapid recovery, papilledema, lethargy, SZR, HA
Subdural: same as epidural, but can be delayed for days/weeks

Question 4

What causes subarachnoid hemorrhage

Answer 4

Rupture of any major blood vessel in brain

Question 5

What would lead you to suspect a subarachnoid hemorrhage

Answer 5

RBCs in CSF on LP

Question 6

Two things that can occur Post-SAH

Answer 6

1. Arachnoid villi become clogged -> transient hydrocephalus

2. Hemolyzed RBCs in CSF -> secondary (chemical) meningitis

Question 7

Two types of uncal herniations

Answer 7

Falx (subfalcine), transtentorial

Question 8

Falx herniation

Answer 8

Cerebrum herniates under falx cerebri

Question 9

Transtentorial herniation

Answer 9

Cerebrum herniates through tentorial notch

Question 10

S/S uncal herniation

Answer 10

Progressive decrease in consciousness

Question 11

What A can be occluded in an uncal herniation, and what can that cause?

Answer 11

PCA occlusion -> ischemic necrosis of primary visual cortex -> contralateral homonymous hemianopsia with macular sparing

Question 12

Tonsillar herniation

Answer 12

Mass in posterior cranial fossa -> cerebellar tonsil herniates through foramen magnum

Question 13

What is compressed in tonsillar herniation

Answer 13

Lower medulla, upper cervical SC

Question 14

What condition can cause tonsillar herniation

Answer 14

Arnold-Chiari malformation

Question 15

Ischemic penumbra

Answer 15

Tissue surrounding the core ischemic territory - is too ischemic to function, but is critically viable and can be rescued with stroke therapy

Question 16

Central cord syndrome: caused by

Answer 16

ASpA disruption

Question 17

Central cord syndrome - what happens to the SC?

Answer 17

Central necrosis and cavitation, development of a syrinx

Question 18

S/S central cord syndrome, anterior, and posterior

Answer 18

Central: abrupt onset neurological S/S with amelioration
Anterior: motor paralysis below lesion, loss of pain and temp
Posterior: loss of proprioception and vibration below lesion

Question 19

What can cause anterior cord syndrome

Answer 19

Flexion injuries, injury to ASpA

Question 20

Lining of ventricular system

Answer 20

Ependymal cells

Question 21

What separates the two lateral ventricles

Answer 21

Septum pellucidum

Question 22

lateral ventricle: anterior horn, body, posterior horn, inferior horn locations

Answer 22

Anterior horn: frontal lobe
Body: parietal lobe
Posterior: occipital lobe
Inferior: temporal lobe

Question 23

Third ventricle location

Answer 23

Between thalami

Question 24

Fourth ventricle shape

Answer 24

Four-sided pyramid

Question 25

Fourth ventricle location

Answer 25

Between cerebellum + pons

Question 26

Base and apex of fourth ventricle

Answer 26

Base: formed by tegmentum of Metencephalon Apex: towards cerebellum

Question 27

Where does the obex lead from the fourth ventricle?

Answer 27

A blind-ended central canal

Question 28

What layer of meninges is related to choroid plexus

Answer 28

Pia mater

Question 29

Hydrocephalus

Answer 29

Increase in cerebral size/mass due to excess CSF in ventricular system, subarachnoid space, or both

Question 30

Clinical signs of hydrocephalus

Answer 30

Strabismus (abducens palsy), sundown gaze, papilledema

Question 31

External hydrocephalus

Answer 31

Excess CSF in subarachnoid space + enlargement of space due to compression of CNS

Question 32

Two types of external hydrocephalus

Answer 32

Supratentorial external and infratentorial external

Question 33

Supratentorial external hydrocephalus is associated with what?

Answer 33

Senile atrophy of cortex (ex: Alzheimer’s)

Question 34

Internal hydrocephalus is also called what?

Answer 34

Non-communicating hydrocephalus

Question 35

What causes internal hydrocephalus

Answer 35

Obstruction somewhere in ventricular system

Question 36

What does internal hydrocephalus cause?

Answer 36

Dilation of ventricles proximal to obstruction

Question 37

Communicating hydrocephalus

Answer 37

Infratentorial external hydrocephalus + internal hydrocephalus

Question 38

Obstruction in communicating hydrocephalus

Answer 38

Obstruction in space between tentorial notch and midbrain, the only communication of CSF from posterior cranial fossa to supratentorial region

Question 39

What happens in communicating hydrocephalus?

Answer 39

Hypertrophy of ventricles + accumulation of CSF in infratentorial area