Intro CNS/Increased Intracranial pressure Norton

Question 1

How rapidly do nuerons divide

Answer 1

they don’t

• permanent
• postmitotic

Question 2

name 3 things that cause acute neuronal injury

Answer 2

hypoxic/Ishcemic insult
infectious insult
toxic insult

Question 3

what happens to neurons in acute neuronal injury

Answer 3

• cell body shrinks
• pyknoisis of nucleus
• cytoplasm intensely eosinophilic

Question 4

pyknosis

Answer 4

chromatin condenses

Question 5

what happens to neurons in subacute and chronic neuronal injury

Answer 5

death over long duration

- reactive gliosis - first sign

Question 6

what is the process of axonal sprouting after axonal injury/transection

Answer 6

• dispersion of Nissl substance to periphery (central Chromatolysis)
• rounding-up
• peripheral displacement of nucleus
• cell death or recovery

Question 7

what happens to the distal axon in axonal injury

Answer 7

degenerative changes

Question 8

name 3 things that cause neural inclusions

Answer 8

aging
genetic disorders
viruses

Question 9

What does aging do to neuronal inclusions

Answer 9

intracytoplasmic lipofuscin

Question 10

where does herpes effect neurons

Answer 10

intranuclear

Question 11

where does rabies impact neurons

Answer 11

intracytoplasmic

Question 12

where does CMV impact neurons

Answer 12

intranuclear and intracytoplasmic

Question 13

Degenerative diseases deposit where in neuron

Answer 13

intracytoplasmic

Question 14

What do Alzheimer, parkinson, and Creutzfeldt-Jacob Disease deposit into the neuron

Answer 14

Alzheimer: neurofibrillary tangles
Parkinson: Lewy Bodies
Creutzfeldt-Jacob disease: Abnormal vacuolization

Question 15

Name 4 types of Glial cells

Answer 15

astrocytes
oligodendrocytes
ependymal cells
microglia

Question 16

function of astrocyte

Answer 16

barrier function; gliosis

Question 17

function of oligodendrocytes

Answer 17

form myelin

Question 18

function of ependymal cells

Answer 18

lines ventricles

Question 19

function of microglia

Answer 19

fixed macrophages

Question 20

Astrocytes are found in which matter ( gray or white) in the brain

Answer 20

both gray and white matter

Question 21

what is gliosis

Answer 21

non-neoplastic proliferation

• indicates CNS injury
• both hypertrophy and hyperplasia

Question 22

Astrocytes have what fibers in them and describe them

Answer 22

Rosenthal fibers: think eosinophilic

Question 23

how does astrocyte cellular swelling occur ? what disease is this

Answer 23

failure of PUMP in hypoxia, hypoglycemia, toxins, Creutzfeld-Jakob disease

Question 24

what is corpora amylacea in astrocytes? what does it indicate and what is a risk factor

Answer 24

• concentrically lamellated
• indicates degenerative change
• increases with age

Question 25

Alzheimer type II astrocyte is caused by what

Answer 25

hyperammonemia

Question 26

what can cause injury to Oligodendrocytes

Answer 26

- in dymyelinating disorders | - viral nuclear inclusion may occur in Progressive Multifocal Leukoencephalopathy

Question 27

what virus may cause extensive ependymal injury

Answer 27

CMV

Question 28

microglia is derived from what embryology layer

Answer 28

mesoderm

Question 29

how does microglia respond to injury

Answer 29

- proliferation - elongating nuclei: rod nuclei - aggregate around necrotic tissue - engulf dying neurons; neuronophagia

Question 30

define vasogenic edema

Answer 30

increased intercellular fluid

Question 31

what is the most common edema

Answer 31

vasogenic edema

Question 32

what is cytotoxic edema

Answer 32

increase intracellular fluid

Question 33

what type of injury would cause cytotixic edema

Answer 33

cell membrane injury ( ischemia)

Question 34

what kind of damage causes cerebral edema

Answer 34

capillary damage - disrupted blood-brain barrier - permeability of new vessels ( tumors )

Question 35

what would an autopsy of a brain of someone who had cerebral edema look like

Answer 35

brain is soft - widened gyri - compressed sulci

Question 36

what secretes the cerebrospinal fluid

Answer 36

choroid plexus

Question 37

what is the flow of the CSF

Answer 37

lateral ventricles - foramen of munro - 3rd ventricle - Cerebral aqueduct ( aqueduct of Sylvius) - 4th ventricle - foramina of Luschka and Magendie - Subarachnoid space - Superior sagittal sinus

Question 38

who and where does CSF get absorbed

Answer 38

arachnoid villi | superior sagittal sinus

Question 39

CSF is between what space in the layers of the brain

Answer 39

arachnoid and pia

Question 40

Hydrocephalus does what to ventricles

Answer 40

dilate them

Question 41

what causes hydrocephalus

Answer 41

- obstruction of flow - failure of resorption - increased secretion: neoplasm of choroid plexus

Question 42

what happens in non-communicating hydrocephalus

Answer 42

CSF does not pass into subarachnoid space

Question 43

what are 2 congenital causes of non-communicating hydrocephalus

Answer 43

aqueductal stenosis or atresia | - Dandy-walker syndrome

Question 44

what are 4 acquired causes of non-communicating hydrocephalus

Answer 44

- neoplasms and cysts - gliosis of aqueduct - obstruction of 4th ventricle opening - organized subarachnoid hemorrhage at base of brain

Question 45

how does communicating hydrocephalus occur

Answer 45

CSF flows out of ventricular system BUT - excess CSF - flow obstructed in subarachnoid space - reabsorption is reduced

Question 46

what are causes of communicating hydrocephalus

Answer 46

- choroid plexus papilloma - deficient absorption of CSF - -dural sinus thrombosis - - organized subarachnoid hemorrhage - - organized meningitis - - deficiency of arachnoid villi

Question 47

what happens in normal pressure hydrocephalus

Answer 47

slow dilation of ventricles due to cerebral atrophy

Question 48

what are clinical symptoms of normal pressure hydrocephalus

Answer 48

- dementia - gait disturbance - incontinence

Question 49

what is the specific definition of increased intracranial pressure

Answer 49

CSF pressure greater than 200mmH2O in lateral decubitus position

Question 50

what can increased intracranial pressure cause

Answer 50

death from herniation

Question 51

what can cause increased cranial pressure

Answer 51

obstructive (non-communicating) hydrocephalus

Question 52

Supratentorial herniation is due to what? displaces what? compresses what?

Answer 52

- unilateral expansion of cerebral hemisphere - displaces cingulate gyrus under falx cerebri - compresses anterior cerebral artery

Question 53

Transtentorial herniation occurs where

Answer 53

uncinate gyrus of temporal lobe through the tentorial opening

Question 54

what does transtentorial herniation compress? what can this cause

Answer 54

contralateral cerebral peduncle can cause duret hemorrhage may occur in midbrain and pons - 3rd cranial nerve: unequal pupils

Question 55

where does Tonsillar herniation occur

Answer 55

cerebellar tonsils through foramen magnum

Question 56

what does Tonsillar herniation compress

Answer 56

medulla ( death)

Question 57

what can cause tonsillar herniation

Answer 57

- increased intracranial pressure | - lumbar puncture done

Question 58

what are 3 clinical signs and symptoms for increased intracranial pressure

Answer 58

- headache - vomiting - papilledema

Question 59

what procedure should not be done for someone who has increased intracranial pressure

Answer 59

NO LUMBAR PUNCTURE

Question 60

what are 2 physical ways ICP increased can be treated

Answer 60

- remove mass - shunt - mechanical ventilation

Question 61

what chemicals can be used to treat cerebral edema

Answer 61

Mannitol | Corticosteroids