Pathology of Cerebrovascular Disease

Question 1

what is a stroke?

Answer 1

Focal neurological deficit due to disruption of its blood supply
reduction in oxygen and nutrients cause damage to brain tissue

Question 2

what is a focal neurological deficit?

Answer 2

loss of function affecting a specific region of the central nervous system

Question 3

what is the most common type of stroke?

Answer 3

(85%) result from a blood vessel being blocked by a thrombus – ischaemic stroke

Question 4

what is the less common type of stroke?

Answer 4

Around one in ten strokes arise from a ruptured blood vessel causing a haemorrhage

Question 5

what are the symptoms of a stroke?

Answer 5

Sudden weakness or numbness - face, arm etc (usually unilateral)
confusion-difficulty speaking/understanding speech
difficulty seeing
difficulty walking, dizziness, coordination loss
severe headache
Unconsciousness

Question 6

what is a Transient ischaemic attack (TIA)?

Answer 6

Symptoms and signs last <24hr

Question 7

what is a Minor stoke?

Answer 7

> 24hr but minor neurological deficit

Question 8

what is a Disabling stoke?

Answer 8

> 24hr with persisting disability that impairs independence

Question 9

what brain damage can a few minutes of hypoxia or anoxia cause?

Answer 9

brain ischaemia
Can lead to infarction
Damage to neurones is permanent
Neurones do not regenerate

Question 10

what are 85% of strokes treated with?

Answer 10

thrombolysis

Question 11

what are causes of CNS ischaemia?

Answer 11

Atherosclerosis
Thrombosis/Embolism 
Hypotension 
Cardiac arrest
Massive blood loss
Arterial spasm following subarachnoid haemorrhage
Systemic vascular disease
Mechanical compression 
Venous obstruction

Question 12

when does cerebral infarction occur?

Answer 12

Blockage to major artery most within internal carotid artery (especially middle cerebral artery)

Question 13

which parts of the brain are most affected by acute cerebral cortex ischaemia?

Answer 13

Cerebral hemispheres, internal capsule (most common)
Contralateral hemiparesis
Neurones die fast; supportive (glial) tissues are more robust
Lose grey-white matter definition

Question 14

what are the underlying causes of thrombotic stroke?

Answer 14

arteriosclerosis, smoking, diabetes

Question 15

what are the underlying causes of embolic stroke?

Answer 15

cardiac arrhythmia, thoracic aortic aneurysm

Question 16

what is Watershed” infarction?

Answer 16

occur at the border between cerebral vascular territories where the tissue is furthest from arterial supply and thus most vulnerable to reductions in perfusion
(Area 7 most at risk)

Question 17

what parts of the brain are most sensitive to global ischaemia?

Answer 17

Neurones in the superficial cortex, hippocampus, thalamus, cerebellum

Question 18

what is global ischaemia?

Answer 18

occurs when blood flow to the brain is halted or drastically reduced
commonly caused by cardiac arrest
MAP less than 60mmHg systolic is risk

Question 19

what is the CNS equivalent of fibrosis?

Answer 19

Loss of neurones causes foamy macrophages –repair process leading to GLIOSIS

Question 20

what is the pathogenesis of a haemorrhagic stroke?

Answer 20

Rupture of a small artery usually at a bifurcation leading to catastrophic haemorrhage

Question 21

describe an Intracerebral haemorrhage

Answer 21

Associated with systemic hypertension in over 50s
80% of these in basal ganglia
Brainstem, cerebellum, cerebral cortex

Question 22

what is the most common cause of non-traumatic subarachnoid haemorrhage?

Answer 22

Rupture of saccular (Berry) aneurysm on circle of Willis

Question 23

where in the circle of willis is a Subarachnoid haemorrhage most likely to occur?

Answer 23

Branching points of on the anterior part of the circle of Willis
Internal carotid, anterior communicating artery and middle cerebral artery most common

Question 24

what is the average size of a Subarachnoid haemorrhage?

Answer 24

Mostly <10mm but up to 50-60 mm seen

Contain thrombus so imaging can underestimate true size

Question 25

what is an infantile Interventricular haemorrhage?

Answer 25

Hypoxia in premature infants
Babies in NICU
Poor outcome

Question 26

what are the consequences of an intracranial haemorrhage?

Answer 26

Death because of rapid increase in intracranial pressure – especially subarachnoid
Clinical features of stroke
Headache especially in subarachnoid
Secondary infarction – local effect of mass lesion and ICP effect
Long-term survivors lose brain tissue – cystic