Stroke

Question 1

Stroke

Answer 1

Syndrome of rapid onset neurological defect caused by a reduction in the blood supply due to cerebral infarction or haemorrhage

Question 2

Ischaemic stroke

Answer 2

Occlusion of an intracranial or neck vessel leading to ischaemia and subsequent infarction of brain tissue

Question 3

Haemorrhagic stroke

Answer 3

Bleeding into or around the brain classically due to a burst aneurism

Question 4

Which stroke type is more common

Answer 4

Ischaemic

Question 5

4 mechanisms of ischaemic stroke

Answer 5

Thrombosis
Embolism
Systemic hypoperfusion - Watershed stroke
Venous sinus thrombosis

Question 6

Do thrombi or emboli more commonly cause stroke

Answer 6

Thrombi

Question 7

How does atherosclerosis form

Answer 7

Endothelial damage -> lipoproteins and monocytes adhere to vessel wall + enter intima -> monocytes differentiate to macrophages -> macrophages engulf lipoproteins becoming foam cells -> cholesterol and foam cells accumulate forming fatty streak -> foam cells release pro inflammatory cytokines -> smooth muscle proliferation + CT deposition -> fibrous cover and necrotic cord form

Question 8

Foam cell

Answer 8

Macrophages that have engulfed cholesterol

Question 9

What is the first step in atheroma formation

Answer 9

Endothelial damage

Question 10

How do foam cells cause smooth muscle cell proliferation

Answer 10

Release pro inflammatory cytokines

Question 11

Why can atheroma form a necrotic core

Answer 11

Lack of capillaries

Question 12

How can atheroma cause thrombosis

Answer 12

Plaque ruptures removing the endothelium and exposing fibrous cap, which causes clotting

Question 13

2 types of Haemorrhagic stroke

Answer 13

Intracerebral
Subarachnoid

Question 14

Most important stroke risk factor

Answer 14

Hypertension

Question 15

Main symptom of subarachnoid haemorrhage

Answer 15

Thunderclap headache

Question 16

What investigation can identify >95% Haemorrhagic stroke

Answer 16

CT Scan

Question 17

What investigation is ordered if Haemorrhagic stroke suspected but CT clear

Answer 17

Lumbar puncture

Question 18

What causes a watershed stroke

Answer 18

Systemic hypoperfusion

Question 19

Stroke symptoms

Answer 19

Face asymmetry
Slurred speech
Difficulty raising both arms
Headache
Confusion
Aphasia
Dizziness
Loss of balance
Visual disturbance

Question 20

4 categories in bamford stroke classification

Answer 20

Total anterior circulation stroke
Partial anterior circulation stroke
Lacunae syndrome
Posterior circulation syndrome

Question 21

What is lacunae syndrome

Answer 21

Small strokes in deep area of brain

Question 22

Stroke risk factors

Answer 22

Age
Hypertension
Diabetes
Atrial fibrillation
Hyperlipidaemia
Smoking
Obstructive sleep apnea

Question 23

How are strokes prevented

Answer 23

Treat risk factors

Question 24

What can cause cerebral necrosis

Answer 24

Mechanical compression
Cerebral oedema
Excitotoxicity

Question 25

How does cerebral oedema form

Answer 25

Decr ATP -> Na pump function limited -> incr Na conc in neurones -> water enters

Question 26

How can cerebral oedema lead to death

Answer 26

Skull limits expansion so cerebral veins compressed and intracerebral pressure increased

Question 27

Coning

Answer 27

Cerebella herniation of tonsils through foramen magnum

Question 28

What causes coning

Answer 28

Incr intracranial pressure

Question 29

How does brain coning cause death

Answer 29

Compression of lower brainstem and upper cervical spinal cord

Question 30

What triggers excitotoxicity

Answer 30

Ischaemia

Question 31

What is excitotoxicity

Answer 31

Incr glutamate in synapses -> NMDA receptors activated -> Ca2+ influx -> incr intracellular Ca -> cell death

Question 32

How does incr Ca2+ conc in cell cause apoptosis and necrotic cell death

Answer 32

Free radical release Protease activation Nitric oxide formation

Question 33

Penumbra

Answer 33

Potentially salvageable brain tissue

Question 34

What is the target for acute stroke therapy

Answer 34

Penumbra - may be able to save cells

Question 35

What is the dead area of brain tissue after a stroke called

Answer 35

Ischaemic core

Question 36

Why is non contrast CT used for in suspected strokes

Answer 36

Rule out/in haemorrhage

Question 37

What imaging may be used in stroke diagnosis

Answer 37

CT MRI Carotid ultrasound

Question 38

Why may carotid ultrasound be used in stroke investigation

Answer 38

Check for atherosclerosis

Question 39

Acute stroke therapies

Answer 39

Thrombolysis Mechanical thrombectomy

Question 40

Thrombolysis

Answer 40

Intravenous fibrinolytic therapy using altepase to break down clot

Question 41

When can Thrombolysis be used

Answer 41

Within 4.5 hrs of stroke onset Haemorrhage clearly excluded by imaging

Question 42

Thrombolysis contraindications

Answer 42

intracranial haemorrhage history Stroke in last 3 months Major surgery or sig trauma in last 3 months

Question 43

Mechanical thrombectomy

Answer 43

Endovascular removal of a thrombus from a large artery

Question 44

When can mechanical thrombectomy be used

Answer 44

Confirmed ischaemic stroke in large artery

Question 45

TIA

Answer 45

Sudden loss of function with complete recovery

Question 46

Anterior circulation TIA signs and symptoms

Answer 46

Unilateral weakness Aphasia Amaurosis fugax Hemisensory loss Hemianopic visual loss

Question 47

Posterior circulation TIA signs and symptoms

Answer 47

Diplopia Vertigo Vomiting Choking Dysarthria Ataxia Hemisensory loss Bilateral visual loss

Question 48

Acute TIA management

Answer 48

Aspirin TIA clinic with 24hrs