22.8 Path: Stroke

Question 1

What types of strokes are there?

Answer 1

Infarction (75%)
Haemorrhage (20%)
Subarachnoid haemorrhage (5%)

Question 2

What is the epidemiology of stroke?

Answer 2

Third leading cause of death
10% of all deaths
Much morbidity in survivors

Question 3

What are some risk factors for cerebral infarction?

Answer 3

Aging, hypertension, cardiac disease (atrial fib), hyperlipidaemia, diabetes mellitus, hypercoaguable states, smoking, obesity

Question 4

How does cerebral infarction occur?

What can this be due to?

Answer 4

Necrosis due to vessel occlusion or hypoperfusion

Due to:
Pump failure
Narrowed lumen (atherosclerosis, thrombosis, vessel thickening)

Question 5

What is the pathogensis of cerebral infarction?

Answer 5

Cardiac
Large artery occlusion (thromb/emb)
Small vessel occlusion (thromb/emb)
Venous occlusion (thromb)

Question 6

What can be some cardiac causes of infarction?

Answer 6

Vegetations on mitral valve
Bacterial/non b. endocarditis
Probe-patent intraatrial septum (young people)

Question 7

What are the common sites of atherosclerosis in the circle of willis?

Answer 7

Basilar artery
Vertebral artery junction
Carotid vessels

Question 8

What is a surgical intervention for atherosclerosis?

Answer 8

Endarterectomy (strip away plaque)

Question 9

What happens early on–>36hrs and beyond after stroke?

Answer 9

Early on: no visible change
Cytotoxic oedema (can't treat)

36hrs: necrotic tissue swells (midline shift), narrowed ventricles

Beyond: MPs, angiogenesis, liquefactive necrosis

Months–>yrs: hole, gliosis around edges

Question 10

What can occur with hyalinearteriolosclerosis?

Answer 10

Micro aneurysms

Question 11

Why do people with cerebral infarction die?

Answer 11

Vital centres/cerebral swelling

Pneumonia, CV disease, pulmonary thromboembolism

Question 12

What are the causes of intracerebral haemorrhage?

Answer 12

Hypertension (hyaline arteriolosclerosis)
Congophilic (amyloid) angiopathy (superficial vessels, alzheimers association)
Blood disorders (leukaemia)
Tumour
Vasculitis
Vascular malformation
Drugs

Question 13

What are some causes of subarachnoid haemorrhage (non traumatic)?

Answer 13

Berry aneurysm (rupture of saccular)
Mycotic/atherosclerotic rupture
Intracerebral haemorrhage

Question 14

What are some risk factors for developing saccular aneurysm?

Answer 14

Sex (F), age
Polycystic kidney disease
Hypertension
Collagen III deficiency
Smoking/alcohol

Question 15

Where do saccular aneurysm soccur?

Answer 15

Arterial bifurcations (congenital weakness sites)
Anterior>post circulation

E.g. MCA bifurcation, ICA/PComA, AComA

Question 16

What are some complications of aneurysm rupture?

Answer 16

E.g. if not clipped,
Subarachnoid haemorrhage
Cerebral oedema/increased ICP
Vasospasm, infarction
Ventricular obstruction-hydrocephalus