Strokes

Question 1

That is a TIA?

Answer 1

A stroke but they recover within 24 hrs of onset of symptoms

Question 2

What is a stroke?

Answer 2

Damage or killing of brain cells starved of oxygen as a result of blood supply to part of the brain being cut off.

Question 3

Describe the changes seen on CT of someone with an ischaemic stroke?

Answer 3

Sometimes seen hypersense artery, grey matter becomes hypodense (darker) and loss of white. grey matter differentiation

Question 4

Describe the changes seen with CT of haemorrhagic stroke?

Answer 4

Hyperdense area (white) seen as location of bleed

Question 5

Where can emboli causing strokes come from?

Answer 5

AF, prosthetic heart valves, septic endocarditis, aorta, carotid sinus, vertebral/ basilar arteries, vasculitis, sickle cell anaemia, cocaine (coke stroke)

Question 6

Which part of the brain will be affected by left anterior cerebral artery strokes?

Answer 6

The medial aspects of the left frontal and parietal lobes and anterior part of the corpus callosum

Question 7

Describe 3 deficits seen with left anterior cerebral artery strokes?

Answer 7

• medial motor and sensory homonculus loss= contralateral loss of all modalities in lower limbs + spinal shock and then UMN signs in contralateral lower limbs
• loss of volunatry micturition as L center is found in paracentral lobule of parietal lobes
• anterior corpus callosum loss may lead to split brain syndrome or alien hand syndrome

Question 8

Which areas of the brain does the middle cerebral artery supply?

Answer 8

the lateral parietal and temporal lobes- basal ganglia, internal capsule, macular cortex

Question 9

What is a malignant MCA stroke?

Answer 9

Occlusion to the main trunk of the middle cerebral artery leading to significant odema and swelling which often leads to death and coma

Question 10

What is the difference in motor and sensory loss in MCA strokes before and after the lenticulostriate arteries branch off.

Answer 10

If after- lateral motor and sensory homonculus lost leading to contralateral sensory loss of all modalities in upper limb and face + contralateral motor loss of upper limb and face (spinal shock then UMN signs).
If before- lenticulostriate arteries also lose blood supply -> loss of blood supply to internal capsule-> motor loss of contralateral lower limb also

Question 11

What is the difference in visual loss due to proximal and distal MCA strokes?

Answer 11

Proximal= superior AND inferior radiations affected-> contralateral homonymous hemianopia
Distal= superior OR inferior radiations affected-> contralateral superior or inferior quadrantanopia

Question 12

What type of stroke may lead to a global aphasia?

Answer 12

Proximal, left MCA stroke (main trunk)- may be before or after lenticulostriate artery branches

Question 13

Occlusion of which divisions of the MCA will lead to receptive and expressive aphasias?

Answer 13

Receptive= wernickes lost= inferior division of MCA stroke (left)
Expressive= brocas area lost= superior division of MCA stroke

Question 14

What artery has had a stroke if the pt experiences hemispacial neglect, tactile extinction (can feel touch on both sides but not recognise touch on right if touched on both sides at once), visual extinction and anosognosia (deny having disability)?

Answer 14

Right MCA- less likely to get aphasias and motor/ sensory losses as these generally controlled by left hemisphere

Question 15

What stroke is most likely to cause a contralateral homonymous hemianopia with macula sparing?

Answer 15

Posterior cerebral artery stroke (deep branches of MCA supply macula region)

Question 16

Describe the possible signs and symptoms seen with a distal cerebellar artery stroke?

Answer 16

dysdiadochokinesis, ataxia, nystagmus, intention tremour, slurred speech, hypotonia

Question 17

Describe other than cerebellar signs, what may be affected in proximal cerebellar artery strokes?

Answer 17

Brain stem effected:

• ipsilateral cranial nerve lesions: CNIII-> XII
• contralateral motor and sensory loss in all modalities (all ascending and descending fibres have decussated at or before the medulla)

Question 18

What type of stroke may cause bilateral blindness?

Answer 18

A basilar artery stroke occluding both posterior cerebellar arteries

Question 19

Other than blindness, name 3 other effects basilar artery strokes could have?

Answer 19

• occlusion of both superior cerebellar arteries leading to bilateral midbrain and cerebellar signs
• bilateral pontine artery occlusion leading to locked in syndrome (CNI-IV + cerebrum, reticular formation and ascending sensory info but all motor functions other than eyes lost)
• Bilateral anaesthesia due to thalamic infarction (supplied by deep branches of PCA)

Question 20

What is a lacunar stroke?

Answer 20

Stroke of small penetrating arteries- eg lenticulostriate arteries, thalamoperforatory artery, basilar artery perforators

Question 21

Occlusion of which vessel will lead to a contralateral hemiparesis (paralysis of one side of body, UMN signs)

Answer 21

Lenticulostriate arteries (branch off MCA)- as supply internal capsule.

Question 22

Occlusion of which blood vessel will lead to a pure contralateral sensory loss of all modalities on one side of the body?

Answer 22

Thalamoperforator artery- branch of PCA which goes to thalamus

Question 23

Name 4 lacunar stroke syndromes?

Answer 23

pure motor, pure sensory, mixed motor and sensory (lenticulostriate artery stroke), ataxic hemiparesis (lenticulostriate artery), clumsy hand dysarthria (basilar artery perforators)