Stroke - ischaemic

Question 1

Define what a stroke is

Answer 1

It is rapidly developing clinical symptoms and/or signs of focal (sometimes global) of loss of brain function, with symptoms lasting >24hrs or leading to death due to infarction or haemorrhage (vascular origin)

Question 2

Define what a TIA is

Answer 2

TIA = transient ischaemic attack or ‘‘mini stroke’’ it is caused by a temporary disruption in the blood supply to part of the brain. Symptoms can be similar to a stroke but symptoms usually last a few mins to hrs and fully resolve within 24hrs

As if they didnt this would be a stroke

Question 3

What are the 3 main different types of stroke ?

Answer 3

1. Infarction
2. Haemorrhage
3. Subarachnoid haemorrhage

Stroke is subdivided into ischaemic stroke (caused by vascular occlusion or stenosis) and haemorrhagic stroke (caused by vascular rupture, resulting in intraparenchymal and/or subarachnoid haemorrhage)

Question 4

What is the most common type of stroke ?

Answer 4

• Ischaemic, they account for 85% of strokes
• Haemorrhagic type account for the rest

Question 5

Define what an ischaemic stroke is due to

Answer 5

It is due to a blood cot forming in an artery leading to the brain or within one of the small vessels deep within the brain, called a cerebral thrombosis

Question 6

What are the 3 main different types of ischaemic strokes ?

Answer 6

1. Cardioembolic - clot blocking artery has travelled to artery it occludes from somewhere more proximal in the arteries or the heart
2. Atheroembolic - clot blocking artery formed at the site it is occluding
3. Small vessel disease

Question 7

What are the 2 main types of ischaemic stroke that you need to differentiate between and why ?

Answer 7

Decide if it is a cardioembolic or atheroembolic stroke as the follow up management differs between the two

Question 8

What are the general signs/symptoms suggestive of stroke ?

Answer 8

Think FAST - facial dropping, arm weakness, speech difficulty, = time to call 999

Some of the symptoms are listed below:

• Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body
• Sudden confusion, trouble speaking, or difficulty understanding speech
• Sudden trouble seeing in one or both eyes
• Sudden trouble walking, dizziness, loss of balance, or lack of coordination
• Sudden severe headache with no known cause

Question 9

What do the focal signs of a stroke generally depend on ?

Answer 9

The affected artery

Question 10

What are the 3 vessels which anastomse together to form the circle of willis ?

Answer 10

• The 2 internal carotid arteries
• The basillar artery (formed by joining of the 2 vertebral arteries)

Question 11

What are the 3 pairs of arteries (as have a R and L part ot the brain) given off by the circle of willis and what do they supply ?

Answer 11

1. Anterior cerebral arteries - supplies most midline portions of the frontal lobes and superior medial parietal lobes.
2. Middle cerebral arteries - supplies the lateral part of each hemisphere
3. Posterior cerebral arteries - supplies the occipital lobe

Question 12

What are the anterior and middle cerebral arteries branches off ?

Answer 12

The internal carotids

Question 13

What is are the posterior cerebral arteries branches of ?

Answer 13

The basillar artery

Question 14

What are the focal signs present in a stroke which could suggest an anterior cerebral artery infarct ?

Answer 14

• Occulsion may cause a weak, numb contralteral leg to the occulsion +/- similar, if milder arm symptoms to the leg again on opposite side to the occlusion. - look out for weakness and sensory loss in contralateral leg
• The face is spared
• Frontal lobe dysfunction e.g. speech

Question 15

What are the focal signs present in a stroke which could suggest a middle cerebral artery infarct ?

Answer 15

• Note that the MCA supplies the major bulk of the motor and sensory cortex
• Contralateral hemiparesis (weakness of one side of the body)
• Hemisensory loss esp face and arm
• Contralateral homonymous heminopia due to involvement of the optic radiation
• Cognitive change e.g. dysphagia with lesions on dominant side
• +/- Visuo-spatial awareness (cant get dressed and gets lost) with lesions on non-dominant side

Question 16

What are the focal signs which suggest a posterior cerebral artery infarct ?

Answer 16

Contralateral homonymous heminopia often with macular sparing

Visual agnosia = a condition in which a person can see but cannot recognize or interpret visual information

Question 17

The carotid artery is also a site for occulsion what happens when this is occluded ?

Answer 17

At worst it can cause total fatal infarction of anterior 2/3rds of its hemisphere but more commonly it presents like a middle cerebral artery occlusion

Contra-lateral weakness or sensory loss. If dominant hemisphere, may be aphasia or apraxia ==> like a MCA infarct

Question 18

What does the vertobasillar (verterbal and basillar arteries) circulation supply ?

Answer 18

Supplies the cerebellum, brainstem, occipital lobes, occlusion causes signs relating to any or all 3

Question 19

What are some of the sign/symptoms which can present which suggest an occulsion in the vertebrobasillar circulation ?

Answer 19

• Hemianopia
• cortical blindness
• diplopia
• vertigo
• nystagmus
• ataxia (lack of voluntary coordination of muscle movements that includes gait abnormality)
• dysarthria (difficult or unclear articulation of speech)
• Dysphagia
• hemi or quadraplegia
• Unilateral or bilateral sensory symptoms
• hiccups
• Coma

Question 20

What is meant by lateral medullary syndrome and what causes it ?

Answer 20

This is infarction of the lateral medulla and inferior cerebellar surface due to occlusion of one of the vertebral arteries or posterior inferior cerebellar arteries

Question 21

What are the range of symptoms/signs caused by lateral medullary syndrome ?

Answer 21

• Vertigo
• Vomiting
• Dysphagia
• Nystagmus
• Ipsilateral ataxia
• Soft palate paralysis
• Ipsilaterla horner syndrome (decreased pupil size, a drooping eyelid and decreased sweating on the affected side of your face)
• Sensory loss on ipsilateral face and contralteral trunk and limbs

Question 22

What is locked in syndrome and what is it caused by ?

Answer 22

It is where damage to the ventral pons occurs due to pontine artery occlusion

Question 23

What are the characteristic features suggesting locked in syndrome?

Answer 23

Patient unable to move but retain full congnition and awareness communicating by blinking, electronic boards or computers

Question 24

Define what a lacunar stroke

Answer 24

• Lacunar infarcts are small (<15 mm) infarcts in the distal distribution of deep penetrating vessels
• Most lacunar infarcts are clinically silent, but repeated episodes are associated with vascular dementia. Symptomatic patients may present with lacunar stroke syndrome (LACS), one of five distinct syndromes.

Question 25

How are lacunar strokes differentiated from cortical strokes ?

Answer 25

Unlike cortical strokes, patients with lacunar stroke syndromes do not exhibit any cortical signs such as aphasia, agnosia, sensory neglect or extinction, apraxia, visual field defects, or cortical sensory loss (e.g. agraphaesthesia, loss of two-point discrimination, loss of joint position sense, astereognosis).

Question 26

Briefly what are the 5 different types of lacunar strokes ?

Answer 26

1. Pure motor stroke/hemiparesis - infarct affects the internal capsule, characterised by contralateral hemiparesis that typically affects the face, arm, or leg in approximately equal measure. A 'pyramidal' pattern of weakness may also be present. 2. Ataxic hemiparesis - again infarct affects internal capsule (just a different bit) displays a combination of cerebellar and motor symptoms, including 'pyramidal' weakness, on the ipsilateral side of the body. 3. Dysarthria-clumsy hand syndrome - contralateral 'clumsiness' (i.e. weakness) of the hand 4. Pure sensory stroke - due to infarct in the thalamus characterised by contralateral numbness of the face, arm and leg. 5. Mixed sensorimotor stroke - infraction affecting thalamus and internal capsule, characterised by contralateral hemiparesis and sensory impairment of the face, arm and leg.

Question 27

What features would suggest Posterior inferior cerebellar artery (lateral medullary syndrome, Wallenberg syndrome)?

Answer 27

* Ipsilateral: facial pain and temperature loss * Contralateral: limb/torso pain and temperature loss * Ataxia, nystagmus

Question 28

What features would suggest an Anterior inferior cerebellar artery (lateral pontine syndrome) infarct?

Answer 28

Symptoms are similar to Wallenberg's (see above), but: Ipsilateral: facial paralysis and deafness

Question 29

What features would suggest a Weber's syndrome (branches of the posterior cerebral artery that supply the midbrain)?

Answer 29

Ipsilateral CN III palsy Contralateral weakness of upper and lower extremity

Question 30

What features would suggest a Retinal/ophthalmic artery infarct ?

Answer 30

Amaurosis fugax - transient monocular blindness