Blood supply to the brain and Strokes

Question 1

stroke

Answer 1

is a clinical syndrome characterised by sudden onset of rapidly developing focal or global neurological disturbance which lasts more than 24 hours or leads to death.

Question 2

Transient ischaemic attack (TIA)

Answer 2

transient (less than 24 hours) neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia, without evidence of acute infarction.
- 24hours historically chosen arbitrarily, most <15mins.
THINK FAST

Question 3

ischaemic attack - this accounts for around 80’% of strokes

Answer 3

• Thrombosis
• Embolism
• Hypoperfusion

Carotid stenosis secondary to plaque could lead to
emboli

Question 4

what are the areas first effects by hypo perfusion

Answer 4

watershed areas, these are the areas of the brain that are the most distal to the blood supply

Question 5

what is the penumbra

Answer 5

this is the ‘halo’ that surrounds an area of the brain that has died due to a stroke, it is the area of the brain that is considered to still be saveable

Question 6

LACS

Answer 6

pure motor, pure sensory, sensorimotor, ataxic hemiparesis

Question 7

POCS

Answer 7

Brainstem, cerebellar and/or isolated homonymous hemianopia

Question 8

TACS

Answer 8

triad of hemiparesis (or hemisensory loss), dysphasia (or other higher cortical functions) and homonymous hemianopia

Question 9

PACS

Answer 9

2 of the fractures of TACS or isolated dysphasia or parietal lobe signs ( e.g. inattention, agnosia, apraxia, agraphaesthesia and Alexia)

Question 10

Anterior cerebral artery ischaemic stroke-

Answer 10

• Often occur in conjunction with MCA infarction in the setting of a proximal occlusion
• Contralateral leg weakness and/or sensory loss (may be present and mild in the contralateral leg)
• Typically, there is leg > arm weakness

Question 11

Middle Cerebral Artery stroke

Answer 11

• Contralateral hemiplegia (upper extremity > lower extremity)
• Contralateral Hemisensory loss
• Conjugate eye deviation (looking toward the side of the lesion)
• Contralateral hemianopia

Question 12

Middle Cerebral Artery Stroke- Language

Answer 12

If entire hemisphere- Global aphasia- can’t speak or understand speech
• Inferior division of MCA supplies the lateral surface of the temporal lobe and inferior parietal lobe

Question 13

Middle Cerebral Artery Stroke- Language if Brocas area is effects

Answer 13

Broca’s aphasia- ‘non fluent aphasia’- Broken speech understands speech, struggles to get words out.

Question 14

Middle Cerebral Artery Stroke- Language if Wernikes area is effects

Answer 14

Wernikes aphasia- ‘fluent aphasia’- Word salad- normal sounding speech that doesn’t make sense, doesn’t
comprehend speech.

Question 15

Middle Cerebral Artery stroke- Hemineglect

Answer 15

Inattention/neglect of the contralateral side of space. The right hemisphere attends to both left and right-sided stimuli, but more strongly to stimuli on the left, the left hemisphere only attends to stimuli on the right side.
• Anosognosia- lack of insight into the neurological deficits

Question 16

Posterior cerebral artery stroke-

Answer 16

• Hemianopia- potentially macula sparing
• Dominant hemisphere:
-Alexia without agraphia- patients can write but cannot read -Visual agnosia- difficulty naming objects
• Non-dominant hemisphere:
-Prosopagnosia (difficulty recognizing familiar faces; even their own face in a mirror)
• Bilateral:
-Cortical blindness (termed Anton syndrome). Patients can confabulate

Question 17

Basilar Artery Occlusion

Answer 17

• Coma/hypersomnolence
• Quadriplegia
• Diplopia (gaze palsies/internuclear ophthalmoplegia)
• Sometimes “locked-in” state -awake but quadriplegic, unable to
speak, sometimes able to blink/move eyes
• Bulbar symptoms- facial weakness, dysphagia, dysarthria, or
First described in literature Darolles 1875
dysphonia

Question 18

Lacunar Stroke

Answer 18

Small infarct, typically defined as less than 1.5 cm occlusion of a small penetrating branch artery
• These syndromes lack cortical signs such as aphasia, agnosia, neglect etc
• Examples of affected arteries: Lenticulostriate branches MCA, thalamoperforators from PCA
• Pure motor- contralateral hand/arm weakness: -E.g damage to Internal capsule/corona radiata
• Pure sensory- contralateral arm/leg sensory loss -E.g damage to thalamus

Question 19

Brainstem syndromes

Answer 19

• Caused most often by occlusion of the branches of veterbral/basilar artery for example aneterior inferior cerebellar
• There are many eponymously named brainstem syndromes- you do not need to learn them- just be aware they exist
• If mixed signs- think brainstem lesion

Question 20

Lateral Medullary syndrome

Answer 20

Ipsilateral ataxia, vertigo, nystagmus, and nausea. This results from the involvement of the inferior cerebellar peduncle and vestibular nuclei. This is often the most disabling clinical feature of this condition.

Question 21

scale used for strokes

Answer 21

National Institutes of Health Stroke Scale (NIHSS)

Question 22

Stroke Mimics

The 5 ‘S’s

Answer 22

• Seizures
• Sepsis
• Syncope
• SOL (tumour, subdural) • Somatisation

Question 23

CT perfusion imaging

Answer 23

• assessment of patients presenting in the late time windows, eg 6 to 24 h, or when there is an unknown/unwitnessed time of stroke onset such as a wake-up stroke

Question 24

Secondary Prevention

Answer 24

Anti-thrombotics:ClopidogrelorAspirin+Dipyridamole • ✓ In atrial fibrillation: Warfarin or NOAC (dabigatran,
rixaroxaban, apixaban)

Question 25

Carotid endarterectomy (CEA)

Answer 25

Considered for all symptomatic stroke/TIA patients (without severe disability; MRS 60% provided > 5 yr life-expectancy & peri-operative stroke/death rate < 3%

Question 26

Subarachnoid Hemorrhage

Answer 26

• ‘Like being hit in the back of the head’, ‘worst headache of
life’, sudden LOC, occasionally almost immediate death • 1/3 die 1/3 severely disabled 1/3 recover well

Question 27

Subarachnoid Hemorrhage- most often caused by

Answer 27

aneurysm