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Neurology Year 3 > Pathology > Flashcards

Flashcards in Pathology Deck (58)
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1

What are common causes of acute neuronal injury?

Hypoxia
Ischaemia

2

What is the descriptive term used for neurones affected by acute neuronal injury?

Red Neurones

3

How soon after the acute injury do "Red Neurones" appear?

12-24 hours

4

On examination what do the neurones post injury look like?

Shrinking and angulation of nuclei
Loss of nucleolus
Red cytoplasm
Eosinophilia

5

How do axons appear post injury?

Swelling of the cell body and nucleolus.
Degeneration of axon and myelin sheath distal to the injury.

6

Chronic Degeneratie neuronal atrophy appears how?

Shrunken small dark nuclei
Reactive Gliosis

7

How do oligodendrocytes react to injury?

Loss of myelin sheath
Conduction is reduced
Axons are exposed to injury

8

What are oligodendrocytes susceptible to?

Oxidative stress e.g hypoxia

9

Astrocytes undergoing scar formation and repair can be described as undergoing what?

Gliosis

10

How does early gliosis appear?

Hyperplasia
Hypertrophy
Nucleus enlargement

11

How does late gliosis appear?

Translucent nuclei
Shrunken and dark lying within a dense mass

12

What are ependymal cells susceptible to?

Limited reaction to injury
Usual site of tumour formation or infection

13

Microglia

CNS Macrophage

14

How do microglia appear on inspection?

Form aggregate around area of necrotic or damaged tissue.

15

M2 - Microglia

Anti inflammatory phagocytic cells - More Acute

16

M1 - Microglia

Pro Inflammatory more chronic

17

List some common causes of Hypoxia.

Cerebral Ischaemia
Infarct
Haemorrhage
Trauma
Cardiac Arrest

18

What proportion of the bodies intake of oxygen is used by the brain?

20%

19

By how many times can cerebral blood flow increase to match the demand before supplies of ATP are used up?

2x

20

What s excitotoxicity?

Energy Failure- Hypoxia or hypoglycaemia

21

What is the Pathophysiology behind excitoxicity?

Neuronal depolarisation and re-uptake of transmitters inhibited.
Glutamate is released and builds up.
Glutamate storm
Ca2+ build-up proteases activated.
Mitochondria dysfunction and oxidative stress.

22

List the types of oedema affecting the brain.

Cytotoxic
Ionic
Vasogenic
Haemorrhagic Conversion

23

Causes of Cytotoxic oedema

Intoxication
Severe hypothermia

24

Causes of Ionic oedema

Hyponatraemia
Excess water intake

25

Causes of Vasogenic oedema.

Breakdown in the BBB
Trauma Tumour Inflammation

26

How does a breakdown in the BBB result in vasogenic oedema?

Plasma proteins and insoluble proteins able to cross, water follows via osmosis.

27

Global Cerebral ischaemia is due to.

Generalised reduction in blood flow - Hypovolaemic shock cardiac arrest

28

Focal Cerebral Ischaemia is due to.

Vascular obstruction

29

Which areas are most susceptible to ischaemia?

Neocortex
Hippocampus
Zones between two arterial territories.

30

A cerebral thrombosis is most likely to occur where?

Middle cerebral artery