Stroke [SYMPOSIA]

Question 1

Epidemiology of stroke

Answer 1

Over 100,000 people in UK
have a stroke per year

Lifetime risk is 1 in 6 for
males and 1 in 5 for females

Stroke is the fourth largest
cause of death (7%)

Cost of stoke to society is
£26 billion per year

Question 2

Risk factors for endothelial injury

Answer 2

Hyperlipidamia
Hypertension
smoking
toxins

Question 3

Outline the pathophysiology of stroke

Answer 3

1. Chronic endothelial injury causes increased vascular permeability- infiltration and adhesion of leucocytes, monocyte adhesion
2. Accumulation of lipoproteins- LDL and oxidised LP
3. Monocytes migrate into intima and become macrophages
   - Digest oxidised LDL–> form foam cells
4. Platelet adhesion
5. Factor release
   -From activated platelets, macrophages inducing
   smooth muscle cell recruitment.
6. Smooth muscle cell proliferation
7. Lipid accumulation

Question 4

Presentation of ACA infarct

Answer 4

Predominantly affects the contralateral lower limb
(e.g hemispariesis)

sensory loss in leg

cognitive and personality changes

Question 5

Presentation of Left MCA infarct [2]

Answer 5

Dysphasia

Right sided weakness/numbness

Question 6

Presentation of Right(non-dominant) MCA infarct [2]

Answer 6

Neglect

Left sided weakness/numbness

left visual defect, extinction of left sided stimuli, left sided sensory loss, dysarthria, spatial disorientation(neglect)

Question 7

Presentation of brainstem infarct [5]

Answer 7

May involve diplopia (double vision)

Visual field defect

Facial weakness

Contralateral limb weakness/numbness

Discoordination

Question 8

Critical Ischaemia

How is blood flow measured in the brain?

Answer 8

When blood flow is
<20ml/100g/min

-electrical function stops
neurones still alive for limited time
-reversible within
limited time

When blood flow is 
<10ml/100g/min 
- neuronal cell death
-within minutes 
- irreversible 
-cerebral infarction

-Uses CT perfusion imaging

Question 9

Thrombolysis

Answer 9

Treatment of stroke
Efficacy dependant on:
-Time [quicker=better]
-Length of clot [longer=less efficacy]

Question 10

Antiplatelet agents

Answer 10

Aspirin

Clopidogrel- blocks ADP binding site

Dipyradamole- inhibits cAMP breakdown

Question 11

What is a carotid stenosis? How is it treated?

Answer 11

Narrowing of carotid artery due to atherosclerosis

Thrombus can form and dislodge-> cerebral artery

T: Carotid endaterectomy

• Incision to open artery
• Plaque removed
• Artery repaired

Question 12

Subtypes of ischemic

stroke [5]

Answer 12

Large artery atherosclerosis

Cardioembolism

Small vessel occlusion

Stroke of other determined etiology

Stroke of undetermined etiology

Question 13

Use of CT perfusion imaging

Answer 13

multimodal CT scans

used to estimate time of onset of stroke

looking for a mismatch

only want to intervene when there’s a salvageable area

Question 14

DWI

Answer 14

Diffusion weighted imaging

Ischaemia on CT shows up early

Question 15

Virchow’s triad of stasis

Answer 15

Factors contributing to thrombosis

Hypercoagulable state
vascular wall injury
circulatory stasis

Question 16

Aphasia

Answer 16

An acquired language impairment

• damage to the left cerebral hemisphere
• can affect any modality of language

Patients can have expressive or receptive difficulties

Question 17

Name 2 motor speech disorders

Answer 17

DYSARTHRIA

APRAXIA OF SPEECH

Question 18

DYSARTHRIA

Answer 18

Difficulty in speaking resulting from a weakness/ loss of control of muscles used to make the sounds of speech, e.g. lips, tongue, soft palate, larynx

Speech can sound slurred or unintelligible

Question 19

APRAXIA OF SPEECH

Answer 19

An inability to control the muscles used to form words
messages from the brain are disrupted

Speech is uncoordinated and effortful.

Question 20

Cognitive Communication Disorder

Answer 20

• Damage to frontal regions of the brain (predominantly right-sided)
• executive dysfunction