Stroke Flashcards
Define a stroke
an acute neurological deficit lasting longer than 24 hours due to vascular compromise.
What else is a stroke referred to as?
cerebrovascular accident - CVA
What is the aetiology (causes) of stroke?
Caused by a transient or permanent critical reduction in cerebral blood flow due to arterial occlusion or stenosis.
Ischaemic (85%) of strokes
- Reduction in cerebral blood flow due to arterial occlusion or stenosis. Typically divided into lacunar (affecting blood flow in small arteries), thrombotic and embolic
What can the causes (aetiology) of stroke be divided into?
-
Cardiac:
- Atherosclerotic disease: smoking, hypertension, diabetes, high cholesterol
- Atrial fibrillation
- Paradoxical embolism due to septal abnormality, such as a patent foramen ovale
-
Vascular
- Aortic dissection
- Vertebral dissection
- Vasculitides
-
Haematological
- Hypercoagulability, such as antiphospholipid syndrome
- Sickle cell disease
- Polycythaemia
What are the types of stroke?
Two main types:
Ischaemic and Haemorrhagic
What are ischaemic strokes like?
- Ischaemic stroke → which is when there is a blocked artery that reduces blood flow to the brain
- Ischaemic strokes arethe most common type of stroke.
- The amount of damage they cause is related to the parts of the brain that are affected and how long the brain suffers from reduced blood flow.
What is a Haemorrhagic stroke like?
- when there is an artery in the brain that breaks crating a pool of blood that damages the brain
They happen when a blood clot blocks the flow of blood and oxygen to the brain. These blood clots typically form in areas where the arteries have been narrowed or blocked over time by fatty deposits known as plaques. This process is known as atherosclerosis.
What are not considered Haemorrhagic strokes?
Extradural and subdural
What does the frontal lobe control?
The frontal lobe controls movement and executive function, which is our ability to make decisions.
What does the parietal lobe control?
The parietal lobe processes sensory information which lets us locate exactly where we are physically and guides movement in a three dimensional space.
What does the temporal lobe control?
The temporal lobe plays a role on hearing, smell, memory as wells as visual recognition of faces and language.
What does the occipital lobe control?
The occipital lobe is primarily responsible for vision.
What controls the different slides of your body?
The right cerebrum controls muscles on the left side of your body.
The left cerebrum controls muscles on the right side of your body
What controls the different slides of your body?
The right cerebrum controls muscles on the left side of your body.
The left cerebrum controls muscles on the right side of your body
What does the cerebellum do?
The cerebellum helps with muscle co-ordination and balance.
What does the brainstem do?
The brain stem plays a vital role in functions like heart rate, blood pressure, breathing, gastrointestinal function and consciousness.
What is the composition of the cerebrum?
- Has 2 hemispheres
- each has a cortex
- each cortex has 4 lobes
What is the blood supply of the brain?
The Brian receives blood from:
- L + R internal carotid arteries and L+R vertebral arteries
- together form basilar artery
Branches of internal carotid arteries:
- L+R middle cerebral arteries - supply lateral portions of F,P and T lobes
- anterior cerebral arteries - supply medial portion of the F and P lobes and connect them via the Anterior Communicating Artery
- Posterior communicating arteries - attach to posterior arteries on each side
Branches of vertebral and basilar arteries supply cerebellum and brianstem.
Basilar artery branches:
- L+ R posterior cerebral arteries - supplies the O lobe + some T lobe and thalamus
Main + communicating arteries = Circle of Willis
Can the brain operate with less blood?
In general the brain can get by on diminished blood flow, especially when it happens gradually as that allow for enough time for the collateral circulation to develop, which is where a nearby blood vessel starts sending out branches of blood vessels to serve an area that is in need. But once the supply of the blood os reduced to below the needs of the tissue it causes tissue damage → which is what we call an ischaemic stroke.
What are the mechanisms for an ischaemic stroke?
Endothelial cell dysfunction and embolism
What occurs in an endothelial cell dysfunction?
One mechanism is endothelial cell dysfunction, which is when something inflames or irritates the slippery inner lining of the artery (the tunica intima).
Describe endothelial cell dysfunction in action
One classic irritant is the toxin found in tobacco. It floats around in the blood damaging the endothelium.
That damage becomes a sight for atherosclerosis which is where a plaque forms. This is when a build up of fat, cholesterol, proteins, calcium and immune cells form and start to obstruct arterial blood flow.
This plaque has two parts to it:
- The soft cheesy textured interior
- The hard, fibrous cap
Usually it takes years for plaque to build up, and this slow blockage only partially blocks the arteries, and even though less blood makes it to brain tissue, there is still some blood.
Strokes happen when there is sudden and complete or nearly complete blockage of the artery.
Since plaque sit in the lumen of the blood vessel they are constantly being stressed by mechanical forces from blood flow and it is often the smaller plaques that are more dangerous. Their fibrous caps are softer than the larger ones and are more prone to getting ripped off. Once that happens the inner cheesy filling is exposed to the blood, and is thrombogenic, which means they tend to form clots quickly. Platelets adhere to the exposed cheesy material and they release chemicals that enhance the clotting process. Within a minute that artery can be fully blocked.
What are the most common sites for atherosclerosis?
Branch points in arteries particularly of the internal carotid and the middle cerebral artery are the most common sites for atherosclerosis.
Describe an embolism
- An embolism stroke typically happens when a blood cot breaks off from one location, travels through the blood and gets lodged in a vessel down stream. Typically an artery arteriole or capillary, with a small diameter.
- These blood clots typically emerge from atherosclerosis, but they can also form in the heart. For example stagnant blood flow can form a clot, and blood can stagnate due to an atrial fibrillation, or after a heart attack.
Where can embolisms occur?
- If a clot form on the left atrium, it moves into the left ventricle and from there it has a direct route to the brain.
- On the other hand, if a clot forms in the low-pressure veins or right atrium, then it goes into the tight ventricle and gets lodged in the pulmonary capillaries with no way of getting to the brain.
What exception can affect an embolism route?
- An important exception is if a person has a heart defect like an atrial septal defect that allows blood and potentially a blood clot to go from the right side of the heart over to the left side of the heart.
- In that situation, a venous or right atrial blood clot will have bypassed the pulmonary circulation and established a route to the brain.
What is a lacunar stroke?
A specific type of ischaemic stroke called a Lacunar stroke, they typically involve the deep branches of the middle cerebral artery that feed the basal ganglia.
Lacunar refers to lake, and is called that because after a Lacunar stroke, the damaged brain tissue develops fluid filled pockets called cysts that look like little lakes under the microscope.
What causes a lacunar stroke?
Lacunar strokes develop as a result of hyaline atherosclerosis which is when the arteriole wall gets filled with protein. This can happen as a result of hypertension or diabetes, and can make the artery wall quite thick, reducing the size of the lumen.
What is the pathophysiology of symptoms?
Patients typically have a focal neurological deficit which corresponds to the region of the brain that’s affected e.g.
- An anterior cerebral artery stroke affects the feet and legs.
- A middle cerebral artery stroke affects the hands, arms, face, and the language centers in the dominant hemisphere, including Broca’s and Wernicke’s area.
- A posterior cerebral artery stroke primarily affects the visual cortex, which affects a person’s ability to see clearly.
What pathways can be affected by stroke?
Both motor and sensory fibres may be affected:
- Damage to motor pathways: flaccid paralysis develops almost immediately. And then over the following days to weeks, there’s spastic paralysis and hyperreflexia due to the hyperexcitable stretch reflex.
- Damage to sensory pathways: numbness, reduced pain and vibration sensation.
How do pathways present in stroke patients?
Both motor and sensory symptoms usually happen on the side that’s contralateral from the stroke, except in rare cases of brain stem stroke, where both sides are affected.
What are some other pathophysiology symptoms?
- Atherosclerosis, migraine, vasculitis-reduce cerebral perfusion and/or result in artery-to-artery embolism
- Cardiac pathologies (e.g., atrial fibrillation, myocardial ischaemia/infarction, patent foramen ovale) that lead to cerebral arterial occlusion due to embolism
- Haematological pathologies (e.g., prothrombotic hypercoagulable or hyperaggregable states) that directly precipitate cerebrovascular thrombosis (particularly venous), or facilitate systemic venous or intracardiac thrombus formation and cardioembolism.
What are the statistics on stroke in the UK?
- There are more than 100,000 strokes in the UK each year causing 38,000 deaths, making it a leading cause of death and disability.
- People are most likely to have a stroke over the age of 55.
What is the epidemiology of all strokes?
- Stroke is the third leading cause of mortality in the US and the UK
- The average age for a stroke is 68 to 75 years old
- Stroke rates are higher in Asian and black African populations than in Caucasians
- M>F
What are the clinical manifestations of stroke?
Usually sudden onset followed by gradual decline
Specific symptoms depends on anatomical site of stroke
What are the clinical manifestations in ACA, MCA and PCA stroke?
- Anterior cerebral artery
- Contralateral hemiparesis and sensory loss with lower limbs > upper limbs
- Middle cerebral artery
- Contralateral hemiparesis andsensory loss with upper limbs > lower limbs
- Homonymous hemianopia
- Aphasia: if affecting the ‘dominant’ hemisphere (the left in 95% of right-handed people)
- Hemineglect syndrome: if affecting the ‘non-dominant’ hemisphere; patients fail to be aware of items to one side of space
- Posterior cerebral artery
- Contralateral homonymous hemianopia withmacular sparing
- Visual agnosia
- Contralateral loss of pain and temperature due to spinothalamic damage
What are teh clinical manifestations in vertebrobasilar artery, webers syndrome and lateral medullary syndrome?
- Vertebrobasilar artery
- Cerebellar signs
- Reduced consciousness
- Quadriplegia orhemiplegia
- Weber’s syndrome (midbrain infarct; branches of osteoporosis cerebral artery)
- Oculomotor palsy and contralateral hemiplegia
- Lateral medullary syndrome (posterior inferior cerebellar artery occlusion)
- Ipsilateral facial loss of pain and temperature
- Ipsilateral Horner’s syndrome: miosis (constriction of the pupil), ptosis (drooping of the upper eyelid), and anhidrosis (absence of sweating of the face)
- Ipsilateral cerebellar signs
- Contralateral loss of pain and temperature
What are the clinical manifestations in retinal/opthalmic artery and basilar artery stroke?
- Retinal/ophthalmic artery
Amaurosis fugax - Basilar artery
- ‘Locked in’ syndrome
What are the symptoms of stroke?
- Headache
- Gaze paresis
Uncommon
- Nausea and/or vomiting
- Neck or facial pain
What are the common signs and diagnostic factors?
- Signs/Diagnostic factors
- Unilateral weakness or paralysis in the face, arm or leg
- Dysphasia: Slurred speach
- Ataxia
- Visual disturbance
- Dysarthria
- Arrhythmias, murmurs or pulmonary oedema
What are the uncommon signs and diagnostic factors?
Uncommon
- Vertigo - Miosis, ptosis, and facial anhidrosis (hemilateral) - Decreased level of consciousness or coma
What are the classifications for stroke?
The Bamford classification is commonly used and categorises stroke based on the area of circulation affected.
Bamford classification - blood vessel - criteria
- TACS (Total anterior circulation stroke) - anterior or middle cerebral artery - HHH (hemiplegia, homonymous hemianopia and higher cortical dysfunction, such as dysphasia or neglect)
- PACS (Posterior anterior circulation stroke) - anterior or middle cerebral artery - two or three from above (HHH)
- Lacunar stroke - perforating arteries: usually affects the posterior limb of the internal capsule - there is no higher cortical dysfunction or visual field abnormality. One of the following:
- pure hemimotor or hemisensory loss
- pure sensorimotor loss
- ataxic hemiparesis - Posterior circulation stroke - posterior cerebral or vertebrobasilar artery or branches - One of the following:
- cerebellar syndrome
- isolated homonymous hemianopia
- loss of consciousness
What are the investigations for ischaemic stroke?
- Assessment using ROSIER scale
Recognition of Stroke in the Emergency Room (ROSIER) scale is a variation of FAST (Face, Arm, Speech, Time) and is used to differentiate acute stroke from stroke-mimics
FAST:
- Face: has the face drooped on one side? Can the person smile?
- Arms: can they lift both arms?
- Speech: is the speech slurred or garbled? Can they understand what you’re saying?
- Time: dial 999 immediately if there are any of the features above
What is another way to assess for stroke?
A stroke is possible if the score is > 0 and requires an urgent non-contrast CT head. Once hypoglycaemia has been excluded, assess the following:
- loss of consciousness or syncope -1 point
- seizure activity -1
New, acute onset of:
- asymmetrical facial weakness +1
- asymmetrical leg weakness +1
- Speech disturbance +1
- Visual field defect +1
What are the primary investigations for stroke?
- Non-contrast CT head: first-line imaging.
- CT is usuallynormal in the first few hours of ischaemic stroke but allows exclusion of haemorrhage
- ECG: assess for atrial fibrillation.
- Bloods:
- CT angiogram (CTA): identifies arterial occlusion and should be performed in all patients who are appropriate for thrombectomy
- MRI head: MRI is an alternative to non-contrast CT head; MRI has a higher sensitivity for infarction and the same sensitivity for haemorrhage when compared to CT imaging. MRI is an alternative to con-contrast CT head.
What do you look for when investigating bloods in stroke?
- Screen for risk factors includingHba1c, lipids, clotting screenand rule out stroke mimics such ashypoglycemia and hyponatraemia
- In younger patients, consider ESR, autoantibody and thrombophilia screen
- FBC
- serum glucose
- serum electrolytes
- serum urea and creatinine
- Prothrombin time and PTT (with INR)
- Cardiac enzymes
- In younger patients, consider ESR, autoantibody and thrombophilia screen
What is the difference between MRI and CT in an investigation?
Diffusion-weighted MRI is the gold standard imaging technique. More sensitive but CT is safer and easier to obtain
CT is an alternative.
What other investigations can be considered?
- Echocardiogram:for the exclusion of an intracardiac aneurysm or a septal defect
-
Carotid Doppler ultrasound :stenosis of >70% is an indication forendarterectomyin Europe.
- The stroke must be non-disabling to qualify
- Lumbar puncture: check for small subarachnoid haemorrhage
Investigations to consider
- Serum toxicology screen
How is a suspected ischaemic stroke managed?
- Suspected ischaemic stroke
- Stabilisation and referral to acute stroke unit
Maintain stable blood glucose levels, hydration status and temperature
Blood pressure should not be lowered too much during a stroke because this risks reducing the perfusion to the brain. Unless complications are present, e.g., hypertensive encephalopathy.
-
How do you manage a confirmed ischaemic stroke?
- Confirmed ischaemic stroke
Presentation within 4.5 hours AND thrombolysis not contraindicated
- Supportive care + monitoring - Thrombolysis: Alteplase (intravenous) (Do not delay)
- Alteplase is atissue plasminogen activator that rapidly breaks down clots to reestablish blood flow; and can reverse the effects of a stroke if given in time.
- Given if < 4.5 hours of symptom onset and haemorrhage excluded on imaging
What are the contraindications of thrombolysis?
- Contraindications of thrombolysis
- Examples of thrombolytics include alteplase, tenecteplase and streptokinase.
- The key side effect of thrombolysis is haemorrhage, whilst hypotension and allergic reactions can occur and are more common with streptokinase.
What are some absolute contraindications of thrombolysis?
- intracranial haemorrhage on CT - suspected subarachnoid haemorrhage
- Neurosurgery, head trauma or stroke in past 3 months - uncontrolled hypertension (>185 mmHg SBP or >110 mmHg DBP)
- History of intracranial haemorrhage - known intracranial arteriovenous malformation, neoplasm or aneurysm
- Active internal bleeding - suspected or confirmed endocarditis
- known bleeding diathesis: coagulation or bleed disorders - aortic dissection
What are the relative contraindications of thrombolysis?
- Major surgeries or serious non-head trauma in previous 14 days - history of GI, genitourinary or gynaecological haemorrhage within past 21 days
- Recent lumbar puncture (usually in the past 7 days) - pregnancy
When is a thrombectomy offered?
Thrombectomy(mechanical removal of the clot) may be offered if an occlusion is confirmed on imaging, depending on the location and the time since the symptoms started. It is not used after 24 hours since the onset of symptoms.
What are the conditions of thrombectomy being offered?
- Confirmation of stroke requires CTA or MR angiogrampriorto thrombectomy
- Must score > 5 on NIH Stroke Scale/Score (NIHSS) and pre-stroke functional status < 3 on the modified Rankin scale
When is a thrombectomy offered in a Proximal anterior circulation stroke and proximal posterior circulations trike (basilar or PCA stroke)?
- Proximal anterior circulation stroke: offerthrombectomywithin 6 hours with IV thrombolysis (if within 4.5 hours), or within6 to 24 hours without IV thrombolysisif there is potential to salvage brain tissue (demonstrated as limited infarct core on imaging)
- Proximal posterior circulation stroke (basilar or posterior cerebral artery): considerthrombectomywithin 24 hours with IV thrombolysis (if within 4.5 hours)if there is potential to salvage brain tissue (demonstrated as limited infarct core on imaging)
What else is given for stroke management?
- Antiplatelet agent - aspirin - 300mg daily
- Given as soon as possible once haemorrhage is excluded on CT
Iftreated with thrombolysis, start aspirin after 24 hours once haemorrhage is excluded
Continue until 2 weeks after the onset of stroke symptoms
- Given as soon as possible once haemorrhage is excluded on CT
- Venous thromboembolism prophylaxis plus early mobilisation
- High intensity statin (after 48 hours) - atorvastatin
- Anticoagulation
- If atrial fibrillation is the cause, anticoagulation should not be started until 14 days post-stroke. Patients should be on aspirin 300mg until then.
What is the management when presentation is after 4.5 hours or thrombolysis contraction indicated?
- Presentation after 4.5 hours OR thrombolysis contra-indicated
- Supportive care + monitoring
- Mechanical thrombectomy
- Antiplatelet agent - aspirin - 300mg daily
- Venous thromboembolism prophylaxis plus early mobilisation
- High intensity statin (after 48 hours) - atorvastatin
How is stroke prevented?
-
Clopidogreldaily lifelong is first-line
- Offeraspirin75 mg daily +MR dipyridamoleif clopidogrel is contraindicated
- OfferMR dipyridamole aloneif aspirin and clopidogrel are contraindicated
- High-dose statin e.g. atorvastatin 20-80mg, usually after 48 hours of stroke
- Manage hypertension, diabetes, smoking and other cardiovascular risk factors
- Carotid endarterectomy or stenting in patients with carotid artery disease
What are some complications of ischaemic stroke?
- Deep venous thrombosis: due to immobility
- Aspiration pneumonia: due to dysphagia
- Haemorrhagic transformation of ischaemic stroke
- Depression
- Alteplase-related orolingual oedema
- Neurological sequelae: such as weakness, impaired mobility, Middle cerebral artery syndrome and seizures
- Requirement for nutritional support: such as nasojejunal feeding
- Intracerebral haemorrhage
- Transient ischaemic attack
- Hypertensive encephalopathy
- Hypoglycaemia
- Complicated migraine
- Seizure and postictal deficits
- Wernicke’s encephalopathy
- Brain tumour
- Sepsis
- Ingestion of toxic substances
- Hyponatraemia
- Hypercalcaemia
- Uraemia
What are some differential diagnosis of ischaemic stroke?
- Intracerebral haemorrhage
- Transient ischaemic attack
- Hypertensive encephalopathy
- Hypoglycaemia
- Complicated migraine
- Seizure and postictal deficits
- Wernicke’s encephalopathy
- Brain tumour
- Sepsis
- Ingestion of toxic substances
- Hyponatraemia
- Hypercalcaemia
- Uraemia
What are some strong risk factors?
Strong
- Older age: the average age for a stroke is 68 to 75 years old
- Family history of stroke
- History of ischaemic stroke
- Hypertension: the single greatest risk factor
- Smoking
- Diabetes
- Atrial fibrillation
- Comorbid cardiac conditions
- Carotid artery stenosis
- Sickle cell diseases
- Dyslipidaemia
- Lower levels of education
- Hypercholesterolaemia
- Haematological disease: such as polycythaemia
What are some weak risk factors of ischaemic stroke?
Weak
- Poor dietary nutrition
- Physical inactivity
- Obesity
- Alcohol abuse
-
Medication: such as hormone replacement therapy or the combined oral contraceptive pill
- Oestrogen-containing therapy
- Obstructive sleep apnoea
- Illicit drug use
- Migraine
- HyPerhomocysteinaemia
- Elevated lipoprotein
- Hypercoagulable states
- Elevated C-reactive protein
- Aortic arch plaques
What is the prognosis for ischaemic stroke?
For ischaemic stroke, the prognosis depends on the severity.
A total anterior circulation stroke confers the poorest prognosis.
Regarding thrombolysis, if administered within 3 hours, patients are 30% more likely to have minimal or no disability.
In general, mortality for haemorrhagic stroke is significantly higher than for ischaemic stroke and can be as high as 40%.
What are the driving rules for car and motor cycle?
Car or motorcycle(type 1 license):
- Patients must not drive for1 monthafter a TIA or stroke
- Driving may resume after 1 month if there has beensatisfactory clinical recovery
- Patientsmay not need toinform the DVLA if there is no residual neurological deficit beyond 1 month
- Multiple TIAsover a short period requires no driving for 3 months and the DVLA must be notified
What are the driving rules for heavy good vehicles?
Heavy goods vehicle(type 2 license):
- Patients must not drive for1 yearafter a TIA or stroke and the DVLA must be notified.
- Relicensing may be considered after 1 year if there isno significant residual neurologicalimpairment andno other significant risk factors
What is a haemorrhagic stroke?
- If blood leaks from a blood vessel in or around the brain, this is called a haemorrhagic stroke.
- Bleeding from a single vessel within the brain.
- High blood pressure is the main cause of intracerebral haemorrhagic stroke
What are the subtypes of haemorrhagic stroke?
- Intracerebral: bleeding within the brain parenchyma
- Subarachnoid: bleeding into the subarachnoid space
- Intraventricular: bleeding within the ventricles; prematurity is a very strong risk factor.
What is the circle of Willis comprised of?
The Circle of Willis comprises an anterior circulation, which consists of the branches of the internal carotid, and a posterior circulation which consists of the branches of the vertebrobasilar arteries.
What is the anterior circulation?
- Anterior circulation
- Anterior choroidal artery
- Anterior cerebral artery (ACA)
- Middle cerebral artery (MCA)
What is the posterior circulation?
- Posterior circulation
- Posterior cerebral artery (PCA)
- Basilar artery
- Superior cerebellar artery
- Anterior inferior cerebellar artery
- Posterior inferior cerebellar artery
What is a berry aneurysm?
- Rupture of a saccular ‘berry’ aneurysm is the most common cause of a spontaneous subarachnoid haemorrhage
- ## These occur at points of arterial bifurcation within the Circle of Willis; the junction between theanterior communicatingarteryandACAis the most common location
What are watershed zones?
Watershed zones: account for 5-10% of infarcts
- These areas are furthest from arterial supply and are most vulnerable to reduced perfusion
- Cortical border zone infarction: border of ACA/MCA and MCA/PCA
- Internal border zone infarction: borders of penetrating MCA branches,orborders of the deep branches of the MCA and ACA (resulting in deep white matter infarction)
What is the Broca’s area?
- in the frontal lobe
function: - motor production of speech
Arterial supply: middle cerebral artery
Effects of a lesion: patients can understand speech but can’t produce it themselves (Broca’s aphasia - non-fluent)
What is Wernicke’s area?
- parietal and temporal lobe
Superior temporal gyrus in the dominant hemisphere (brodmann area 22)
Function: understanding speech and using correct words to express thoughts
Arterial supply: middle cerebral artery
Effects of a lesion: patients can produce speech but do not grasp the meaning of spoken words (wernickes aphasia ‘fluent’)
What is cerebral dominance?
- Cerebral dominance
- Majority of people are ‘left dominant’ (95%): this means that the Wernicke’s and Broca’s areas are located in theleft cerebral hemisphere
- A stroke affecting theleft MCAcauses expressive aphasia (Broca’s area) or receptive aphasia (Wernicke’s area)
- In contrast,left-handed peopleare more likely to be ‘right dominant’, meaning that these areas are more likely to be on the right
- Therefore, in left-handed people, aright MCAstroke usually causes aphasia
- MCA stroke affecting a patient’s ‘non-dominant’ hemisphere often results in hemisensory neglect, not aphasia
What is macular sparing?
- The occipital pole is responsible for supplying the macula and has arich anastomosis; this region is also supplied by theMCA
- The macular is often spared in aposterior circulation stroke(e.g. PCA infarct), resulting incontralateral homonymous hemianopia with macular sparing
- This is because of the dual blood supply of the occipital lobe (MCA and PCA)
What is locked in syndrome? (Pseudocoma)
- A condition whereby the patient is fully aware but cannot move or communicate verbally due to almost complete paralysis
- All voluntary muscles are generally affected, except for vertical eye movements and blinking
- It may be caused by a stroke affecting thebasilar artery, thusdenying blood to the pons
- There are also numerous other causes, such as central pontine myelinosis and traumatic brain injury
- In contrast, persistent vegetative state affects the upper portions of the brain but spares the lower portions
What is locked in syndrome? (Pseudocoma)
- A condition whereby the patient is fully aware but cannot move or communicate verbally due to almost complete paralysis
- All voluntary muscles are generally affected, except for vertical eye movements and blinking
- It may be caused by a stroke affecting thebasilar artery, thusdenying blood to the pons
- There are also numerous other causes, such as central pontine myelinosis and traumatic brain injury
- In contrast, persistent vegetative state affects the upper portions of the brain but spares the lower portions
What is the aetiology of Haemorrhagic stroke?
Ruptured blood vessel leading to reduced blood flow.
- Aetiology
-
Haemorrhagic (15%) of strokes
- Ruptured blood vessel leading to reduced blood flow
-
Haemorrhagic (15%) of strokes
