Cerebrovascular Disease Pathology

Question 1

Which cerebral vessel is most commonly affected in thromboembolic disease, mainly because of its position?

Answer 1

MCA

Question 2

What is the important overlying process which can result in both ischaemic and haemorrhagic strokes?

Answer 2

Hypertension

Question 3

What is global hypoxic ischaemic damage?

Answer 3

When the systemic compromise to circulation (e.g. cardiac arrest, hypovolaemic shock) cannot be compensated for by CNS autoregulatory mechanisms

Question 4

Global hypoxic ischaemic damage occurs when MAP reaches what level? What is the significance of this?

Answer 4

50mmHg - this is when autoregulatory mechanisms cannot sufficiently compensate

Question 5

What are watershed areas?

Answer 5

Areas at the peripheries of vascular territories

Question 6

Why do watershed areas contain neurones which are particularly sensitive to hypoxia?

Answer 6

Because they are the most distant from the heart, and the least well supplied

Question 7

Which type of cell found in the CNS is more sensitive to hypoxic damage - neurones or glial cells?

Answer 7

Neurones

Question 8

What is focal ischaemia?

Answer 8

Restriction of blood flow to a localised area of the brain, typically due to a vascular obstruction

Question 9

The presence of atheroma in both intra and extra cerebral blood vessels is a risk factor from stroke. Atheroma can affect all the main cerebral arteries but in general, which is most commonly affected?

Answer 9

Basilar artery

Question 10

Atheroma formation in the extracranial vessels (e.g. carotids and aorta) is significant as these are the source of the majority of which type of stroke?

Answer 10

Embolic

Question 11

Describe why hypertension is a risk factor for both ischaemic and haemorrhagic stroke?

Answer 11

Ischaemic - contributes to atheroma formation and atherosclerosis Haemorrhagic - increases the chance of spontaneous rupture of vessels

Question 12

In an ischaemic stroke, after how long will the necrotic area become visible macroscopically?

Answer 12

48 hours

Question 13

After an ischaemic stroke, what will always remain macroscopically as a permanent marker of the site of an old infarction?

Answer 13

Gliotic scar to start with which will desist to become a cystic gap

Question 14

Microscopically, what is the primary cell type seen within 48 hours of an ischaemic stroke?

Answer 14

Neutrophils

Question 15

Microscopically, what is the primary cell type seen after 48 hours of an ischaemic stroke?

Answer 15

Microglia

Question 16

Around a week after an ischaemic stroke, what pathological process takes place microscopically? What happens?

Answer 16

Reactive gliosis - astrocytes increase in number and size

Question 17

A few weeks after an ischaemic stroke, a cavity begins to form microscopically which is lined by what?

Answer 17

Gliotic scar tissue characterised by astrocytes

Question 18

Give some examples of types of intracranial haemorrhage which can occur due to trauma?

Answer 18

Extradural haematoma, subdural haematoma, contusion

Question 19

What is the commonest cause of spontaneous intracerebral haemorrhage?

Answer 19

Rupture of small cerebral blood vessels (perforating arteries) with walls weakened by hypertension

Question 20

Hypertension is the most common cause of spontaneous intracerebral haemorrhage, what are some others?

Answer 20

AVM, amyloid angiopathy, aneurysm rupture, tumours, clotting dysfunction

Question 21

Intracerebral haemorrhage is most likely to occur in which 4 locations?

Answer 21

Basal ganglia, thalamus, cerebral white matter, cerebellum

Question 22

What is the most common cause of a subarachnoid haemorrhage?

Answer 22

Rupture of a saccular (Berry) aneurysm

Question 23

90% of Berry aneurysms are seen in the territory of which artery?

Answer 23

Internal carotid artery

Question 24

10% of Berry aneurysms are seen in the territory of which arterial system?

Answer 24

Vertebro-basilar circulation

Question 25

Where in the internal carotid artery are Berry aneurysms most likely to be found?

Answer 25

At the arterial bifurcations at the Circle of Willis

Question 26

Because of the high pressure involved or because of the location of vascular lesions, subarachnoid haemorrhage may be associated with what?

Answer 26

Intracerebral haemorrhage

Question 27

What are some examples of mass effect which may be seen with subarachnoid haemorrhage?

Answer 27

Features of oedema, raised ICP

Question 28

Describe the relationship between subarachnoid haemorrhage and hydrocephalus?

Answer 28

Acute hydrocephalus will develop within the first few days, then the chronic type will develop around the second week due to obstruction of flow of CSF in the subarachnoid space

Question 29

Vasospasm can occur as a result of subarachnoid haemorrhage. This brings around vasoconstriction which can lead to what?

Answer 29

Secondary brain ischaemia and infarction

Question 30

What are the three main risk factors for subarachnoid haemorrhage?

Answer 30

Smoking, hypertension and kidney disease

Question 31

What is the typical presentation of a subarachnoid haemorrhage?

Answer 31

Thunderclap headache, vomiting and loss of consciousness

Question 32

What is the outcome of subarachnoid haemorrhage?

Answer 32

50% die within several days of onset, survivors are at risk of hydrocephalus

Question 33

Subarachnoid haemorrhage is more common in which gender? And what age group

Answer 33

Female, usually before the age of 50

Question 34

There is a higher incidence of subarachnoid haemorrhage in patients with what conditions?

Answer 34

Polycystic kidney disease (or known Berry aneurysm), fibromuscular dysplasia, coarctation of the aorta, AVM

Question 35

Hypertensive encephalopathy occurs in severely hypertensive patients - what is this?

Answer 35

When the upper limit of autoregulatory mechanisms is saturated the BBB becomes incapable of resisting movement of plasma proteins into the brain which leads to vasogenic oedema and symptoms of raised ICP

Question 36

Chronic hypertension is associated with the development of what? Where do these most commonly occur?

Answer 36

Micro-aneurysms which occur particularly in small branches of the MCA most commonly in the basal ganglia

Question 37

Microaneurysms which develop as a result of chronic hypertension increase the risk of what?

Answer 37

Intracerebral haemorrhagic stroke

Question 38

Which vessel supplies the area in blue?

Answer 38

Anterior cerebral artery

Question 39

Which vessel supplies the area in pink?

Answer 39

Middle cerebral artery

Question 40

Which vessel supplies the area in green?

Answer 40

Posterior cerebral artery

Question 41

Which vessel supplies the area in blue?

Answer 41

Anterior cerebral artery

Question 42

Which vessel supplies the area in yellow?

Answer 42

Middle cerebral artery

Question 43

Which vessel supplies the areas in red?

Answer 43

Posterior cerebral arteries

Question 44

Which vessel supplies the area in green?

Answer 44

Anterior choroidal artery