Stroke - Aetiology, Features and Long-term management Flashcards
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What is the frontal lobe involved in?
- High level cognitive functions - abstraction, concentration, reasoning
- Memory
- Control of voluntary eye movement
- Motor control of speech (dominant hemisphere)
- Motor cortex
- Urinary continence
- Emotion and personality
What are the functions of the parietal lobe?
- Sensory cortex
- Sensation - touch, pressure, position
- Awareness of parts of the body
- Spatial orientation and visuospatial information - non dominant hemisphere
- Ability to perform learned motor tasks (dominant)
What are the functions of the temporal lobe?
- Primary auditory receptive area
- Comprehension of speech (dominant) – Wernicke’s
- Visual, auditory and olfactory perception
- Important role in learning, memory and emotional affect
What is the function of the occipital lobe?
- Primary visual cortex
- Visual perception
- Involuntary smooth eye movement
What are the main functions of the cerebellum?
Balance and coordination
What are the main components of the brainstem?
- Midbrain
- Pons
- Medulla
How many of the cranial nerves arise from the brainstem?
10 out of 12
What is the definition of a stroke?
Rapidly developing clinical signs of focal (or global) disturbance of cerebral function, with symptoms lasting >/= 24 hrs, or leading to death with no apparent cause other than vascular
What is the definition of a TIA?
A brief episode of neurological dysfunction caused by focal brain or retinal ischemia with clinical symptoms typically lasting less than one hour and without evidence of acute brain infarction
How many neurons can you lose per minute in an ischaemic stroke?
5 million per minute
What proportion of strokes are ischaemic?
85%
What proportion of strokes are haemorrhagic?
15%
What are causes of ischaemic stroke?
-
Atherosclerosis
- Carotid plaques (commonly at junctions - carotid bifurcation, vertebral arteries (basilar))
- Aortic arch plaque
- Flow reducing carotid stenosis
-
Thrombolysis/embolism
- Cardiac emboli - AF, endocarditis, MI (mural thrombus), valve disease, LV thrombi
- Idiopathic
-
Rarer causes
- Arterial dissection
- Venous sinus dissection
- Penetrating artery disease
What are the causes of a haemorrhagic stroke?
- Primary intra-cerebral haemorrhage (hypertension)
- Most commonly in basal ganglia (50%), lobar white matter (20%), pons (10%) and cerebellum 10%
- Secondary haemorrhage
- SAH
- Aterio-venous malformation
What are risk factors for having a stroke?
-
Non modifiable
- Age
- Gender - male
- FH
- Previous stroke
- Deletion polymorphism in ACE gene
- Ethnicity - black/asian
-
Modifiable
- Smoking
- Alcohol
- Diet
- Obesity
- Phyiscal inactivity
- Hyperlipidaemia
- HYPERTENSION
- DM
- Blood ocagulation factors - high fibrinogen, factor 7
-
Other RF
- Atrial fibrillation
- Hypercoaguable states
What are the most common sites for stenosis of the extracerebral arteries?
- Common carotid
- Internal carotid
- Vertebral
- Subclavian
What is the most common cause of ischaemic stroke?
Carotid plaque with arteriogenic emboli - 35%
What are cardioembolic causes of stroke?
- AF
- Cardioversion
- Acute MI + akintic LV - Mural thrombosis
- Infective endocarditis
- Cardiac surgery
- Valvular disease
- Patent foramen ovale/septal defect - DVT can pass through
If someone below the age of 40 presented with a stroke, what might you consider investigating for as a cause?
- Sudden drop in BP >/= 40mmHg
- Carotid artery dissection
- Vasculitis
- SAH
- Venous sinus thrombosis
- Antiphospholipid syndrome
- Thrombophilia
What are 5 impotant points to detrmine when trying to make the diagnosis of stroke?
- What is the neuro deficit?
- Where is the lesion?
- What is the lesion?
- Why has it happened?
- What are the potential complications?
If you had a stroke in the brainstem, where would you see neruological signs?
- Ipsilateral cranial nerve signs
- Contralateral motor signs/Quadraplegia
- Disturbances of gaze and vision
- Locked in syndrome
Are abnormal movements after a stroke normal?
No
Are headaches after a stroke normal?
No
What are the main stroke syndromes?
CLINICALLY CLASSIFIED - OCSP Bamford classification
- TACS
- PACS
- LACS
- POCS
What are general features which are seen in a stroke?
- Motor - clumsy or weak limb
- Sensory loss
- Speech - Dysarthria/Dysphasia
- Neglect / visuospatial problems
- Vision - loss in one eye (amaurosis fugax) or hemianopia
- Gaze palsy
- Ataxia/ vertigo / incoordination / nystagmus
What does the anterior cerebral artery supply?
Motor cortex - leg, frontal lobe, corpus callosum
What does the middle cerebral artery supply?
Motor and sensory cortex
Contraltateral arm and face
Wernikes and brocas in dominant hemisphere
Internal capsule
What is a TACS?
Total anterior circulation stroke
Constellation of symptoms of a patient who clinically appears to have suffered from a total anterior circulation infarct, but who has not yet had any diagnostic imaging (e.g. CT Scan) to confirm the diagnosis.
What are features of a TACS?
3 out of 3 of:
- Complete hemiparesis/numbness - Face, arm and leg (2/3)
- Homonymous hemianopia
- Higher function loss - inattention, dyshasia dominant
What is a PACS?
Partial anterior circulation syndrome
Constellation of symptoms of a patient who clinically appears to have suffered from a partial anterior circulation infarct, but who has not yet had any diagnostic imaging (e.g. CT Scan) to confirm the diagnosis.
What arteries are most commonly affected in a TACS?
Large cortical stroke in middle/anterior cerebral artery area
What arteries are most commonly affected in a PACS?
Cortical stroke in middle/anterior cerebral artery areas
What are features of a PACS?
- 2 of 3 TACS criteria
or
-
One higher cortical deficit:
- Inattention
- Or dysphasia
or
- Monoparesis