Geriatrics and stroke medicine Flashcards
What are the tow arteries that supply the brain?
Internal carotid
Vertebral arteries
Recap - Outline the main roles of the
a) Frontal lobe
b) Temporal Lobe
c) Parietal Lobe
d) occipital lobe
Frontal - decision making, movement, executive function, personality.
Temporal - hearing (primary auditory cortex), memory and language, smell, facial recognition
Parietal - Sensory info
Occipital lobe - Vision
What does the internal carotid artery branch off to supply?
branches off to create the Anterior cerebral artery, as well as posterior communicating artery to join the circle of Willis
After this the ICA continues on as the Middle cerebral artery, which supplies the lateral portions of the cerebrum
What does the middle cerebral artery supply?
· MIDDLE CEREBRAL ARTERY—(huge artery) supplies majority of lateral surface of the hemisphere and deep structures of anterior part of cerebral hemisphere.
After entering the cranium through the foramen magnum, what branches does the vertebral artery give off? What do the 2 vertebral arteries then go on to do?
Give off Spinal arteries, supply the entire length of spine
Gives off The Posterior Inferior cerebellar artery - supplies cerebellum
also gives off a menigeal branch
But after this two vertebral arteries converge to form the basilar artery
What arteries branch off the basilar artery?
Superior cerebellar artery (SCA)
Anterior inferior cerebellar artery (AICA) - Both to supply the cerebellum
The Pontine arteries
What does the posterior cerebral artery go on to supply? What is it a branch of?
Supplies occipital lobe, posteromedial temporal lobes, midbrain, thalamus,
It is the terminal branch of the basilar arteries,
What does the anterior cerebral artery supply?
· ANTERIOR CEREBRAL ARTERY (supplies and runs over Corpus Callosum and supplies Medial aspects of Hemispheres (anteromedial aspects of the cerebrum)
What is a stroke?
An acute neurological deficit lasting more than 24 hours and caused by cerebrovascular aetiology
What are the two types of stroke?
Two kinds of stroke are ischaemic (85%) and haemorrhagic (15%)
The two types of ischaemic events in the brain are a Cerebral infarction (an ischaemic stroke) or a Transient ischaemic attack (TIA)
a TIA is not considered to be an actual stroke
What are the different causes of an ischaemic stroke?
- Cardiac: atherosclerotic disease, AF, Embolism due to septal abnormality
- Vascular: aortic dissection, vertebral dissection
- Haematological: hypercoagulability such as antiphospholipid syndrome, sickle cell disease, polycythaemia
What are the different causes of haemorrhagic strokes?
Intracerebral: bleeding within the brain parenchyma:
- Trauma
- Cerebral amyloid
- Hypertension
Subarachnoid: bleeding between the pia and arachnoid matter
- Trauma
- Berry aneurysm
- Arteriovenous malformation
Intraventricular: bleeding within the ventricles
What are the risk factors for having a stroke?
- Hypertension
- Smoking
- AF
- Vasculitis
- Medication
If the anterior cerebral artery is affected in a stroke where in the body will this present?
Feet and legs
If the middle cerebral artery is affected in a stroke where in the body will be affected?
- Hands and arms
- Face
- Language centres in dominant hemisphere
What are the symptoms of a anterior cerebral artery stroke?
Contralateral hemiparesis and sensory loss more commonly affects the lower limbs
What are the symptoms of a middle cerebral artery stroke?
- Contralateral hemiparesis and sensory loss with upper limbs more affected
- Homonymous hemianopia
- Aphasia: if the affecting dominant hemisphere 95% of right handed people this is the left side
- Hemineglect syndrome if affecting non-dominant hemisphere patients won’t be aware of one side of their body
What are the symptoms of a posterior cerebral artery stroke?
- Contralateral homonymous hemianopiawithmacular sparing
- Contralateral loss of pain and temperature due to spinothalamic damage
What are the symptoms of a vertebrobasilar artery stroke?
- Cerebellar signs
- Reduced consciousness
- Quadriplegia or hemiplegia
What is Weber’s syndrome and what are the symptoms of it?
- A midbrain infarct that leads to oculomotor palsy and contralateral hemiplegia
What are the symptoms of lateral medullary syndrome (posterior inferior cerebellar artery oculsion)
- 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)
- Ipsilateralcerebellar signs
- Contralateralloss of pain and temperature
What is used to classify stokes and how does it do it?
The Bamford classification and it categorises strokes based on the area of circulation affected
What are the different classifications in the Bamford classification?
- Total anterior circulation stroke
- Partial anterior stroke
- Lacunar stroke
- Posterior circulation stroke
What is a TACS?
Total anterior circulation stroke
Blood vessel= anterior or middle cerebral artery
Criteria: all of
- Hemiplegia
- Homonymous hemianopia
- Higher cortical dysfunction
What is a PACS?
Partial anterior circulation stroke
Blood vessel= anterior or middle cerebral artery
Criteria is any two of:
- Hemiplegia
- Homonymous hemianopia
- Higher cortical dysfunction
What is a lacunar stroke?
Blood vessel= perforating arteries
Criteria: there is no higher cortical dysfunction or visual field abnormality and there is one of:
- Pure hemimotor or hemisensory loss
- Ataxic hemiparesis
- Pure sensorimotor loss
What is a PCS?
Posterior circulation stroke
Blood vessel= Posterior cerebral or vertebrobasilar artery
Criteria:
- Cerebellar syndrome
- Isolated homonymous hemianopia
- Loss of consciousness
What is used to identify strokes in hospital?
Recognition of Stroke in the Emergency Room (ROSIER) scale.
What are the criteria for the ROSIER scale?
- Loss of consciousness
- Seizure activity
New, acute onset of:
- Asymmetric facial/arm/leg weakness
- Speech disturbance
- Visual field defect
When would a stroke be possible using the ROSIER scale and what would happen as result?
A stroke is possible if they have any of the criteria and hypoglycaemia has been excluded
WOULD REQUIRE URGENT NON-CONTRAST CT
- Aspirin 300mg stat (after the CT)
What are the initial investigations for a stroke?
Non Contrast CT of head
ECG- to asses for AF
Bloods to look for hyponatremia/hypoglycaemia
Carotid doppler
What is the gold standard test for a stroke?
Diffusion weighted MRI is more sensitive but harder to obtain
What are the differentials for a stroke?
- Hypoglycaemia
- Hyponatremia
- Hypercalcaemia
- Uraemia
- Hepatic encephalopathy
What is the treatment for a ischaemic stroke?
- Antiplatelets Aspirin given as soon as possible once haemorrhagic stroke is excluded
- Thrombolysis: alteplase- given within 4.5 hours of symptom onset
- Thrombectomy must score > 5 on NIH Stroke Scale/Score (NIHSS) and pre-stroke functional status < 3 on the modified Rankin scale
What should be performed before thrombectomy?
CT angiogram (CTA): identifies arterial occlusion
What is given for the prevention of ischaemic strokes?
- Clopidogrel an antiplatelet
- High dose statin
- Carotid stenting
- Manage underlying risks
What are the driving rules after a stroke?
- Must not drive for 1 month after a stroke and can’t drive a HGV for 1 year after a stroke
What is a TIA?
- A transient episode of neurological dysfunction caused by focal brain, spinal cord or retinal ischaemia without acute infarction.
- It usually resolves within 24 hours
What are the symptoms of a TIA in the internal carotid artery?
ACA: weak numb contralateral leg
MCA: body, face drooping w/forehead spared, dysphasia (temporal)
PCA -Homonymous hemianopia: visual field loss on the same side of both eyes
Hemisensory loss
Amaurosis fugax
What are the investigations for a TIA?
- Auscultation: listen for carotid bruit
- CT scan: request an urgent CT scan of the head
- Carotid doppler- look for stenosis
- CT angiography- look for stenosis
What is the management for a TIA?
- First line antiplatelet initially with aspirin 300mg
- Carotid endarterectomy: surgery to remove blockage of >70% on doppler
- Manage cardiovascular risk
What is a crescendo TIA?
Where there are two or more TIAs within a week. It carries a high risk of a stroke
How many people who have a TIA will go on to have a stroke?
10% within 3 months
What are the two categories a haemorrhagic stroke can be split into?
- Intracerebral where the bleeding occurs within the cerebrum
- Subarachnoid when bleeding occurs between the pia and arachnoid matter
What can cause an intracerebral haemorrhage?
- Hypertension causing atherosclerosis and microaneurysms called bouchard aneurysms
- ** Arteriovenous malformations** blood vessels that directly connect an artery to a vein
- Vasculitis/Vascular tumours
- Secondary to an ischaemic stroke- ischaemia causes brain tissue death. If there is reperfusion there’s an increased chance that the damaged vessel might rupture
What are the risk factors for developing an intracerebral stroke?
- Head injury
- Hypertension
- Aneurysm
- Brain tumour
- Anticoagulant
Describe the pathophysiology of an intracerebral haemorrhage?
- Once blood starts to spew from vessel it creates a pool of blood which increases pressure in the skull and outs pressure on nearby cells and vessels. This can lead to brain herniation
What is the presentation of an intracerebral haemorrhage?
- Sudden headache
- Weakness
- Seizure
- Vomiting
- Reduced consciousness
What are the investigations for a intracerebral haemorrhage?
- CT/MRI to confirm size and location of the haemorrhage
What is the management for a intracerebral haemorrhage?
- Correct severe hypertension but avoid hypotension
- Drugs to relieve intercranial pressure mannitol
What are the surgeries that can be performed for an intracerebral haemorrhage?
- Craniotomy part of the skull bone is removed to drain any blood and relieve pressure
- Stereotactic aspiration: aspirate off blood and relieve intracranial pressure guided by a CT scanner. Good for bleeding that is located deeper in the brain
What can cause SAH?
- Trauma is a key factor
- Atraumatic cases are referred to as spontaneous SAH
What are the most common causes of spontaneous SAH?
- Berry aneurysm- they account for 80% of cases.
- Arise at points of bifurcation within the circle of Willis: the junction between the anterior communicating and anterior cerebral artery
- They are associated with **PKD, coarction of the aorta, and connective tissue disorders (Marfan)
What are the risk factors for having a SAH?
- Cocaine use
- Sickle cell anaemia
- Connective tissue disorders
- Neurofibromatosis: tumours form on your nerve tissues
- PKD
- Alcohol excess
What can occur as a result of a subarachnoid haemorrhage?
- Blood vessels that are bathing in a pool of blood can start to intermittently vasoconstrict. If this occurs in the circle of Willis it will reduce the supply of blood flow to the brain causing further injury
- Over time blood in the subarachnoid space can irritate the meninges and cause inflammation which leads to scarring of the surrounding tissue. The scar tissue can obstruct the normal outflow of CSF causing fluid to build up leading to hydrocephalous
What are the signs of a SAH?
- 3rd nerve palsy: if the aneurysm occurs in posterior communicating artery
- 6th nerve palsy a non-specific sign which indicates raised intercranial pressure
- Reduced GCS
What are the symptoms of a SAH?
- Thunderclap headache
- Neck stiffness
- Photophobia
- Vision changes
What are the initial investigations for SAH?
- FBC
- Serum glucose
- Clotting screening
- Urgent non-contrast CT of the head. Blood will cause hyperattenuation (this means becoming more dense on CT will show as white) in the subarachnoid space
What tests would you perform if the CT is negative but a SAH is still suspected?
- Lumbar puncture: will show RBCs or or xanthochromia (yellow pigmentation due to degradation of haemoglobin to bilirubin)
What is given to prevent vasospasm in SAH?
Nimodipine is a CCB and prevents vasospasms
What is the management to stop the bleeding?
SAH
- first-line is endovascular coilingof the aneurysm;
- second-line is surgical clippingvia craniotomy
- If features of raised intracranial pressure: consider intubation with hyperventilation, head elevation (30°) and IV mannitol
What are the complications of a SAH?
- Rebleeding 22% risk at one month
- Vasospasm: accounts for 23% of deaths; at highest risk for the first 2-3 weeks after SAH; treated with (induced) hypertension,hypervolemia andhaemodilution (triple-H therapy).
- Hydrocephalus: acutely managed with external ventricular drain (CSF drainage into an external bag) or a long-term ventriculoperitoneal shunt, if required
- Seizures: seizure-prophylaxis is often administered (e.g. Keppra)
- Hyponatraemia: commonly due to syndrome of inappropriate antidiuretic hormone secretion (SIADH)
What is a subdural haemorrhage?
Bleeding below the dura matter
Who is most likely to suffer from a SDH?
- Elderly
- Alcoholics
What can cause a SDH?
- Brain atrophy: in the elderly the brain shrinks in size meaning the bridging veins are stretched across a wider space
- Alcohol abuse causes the walls of the veins to thin out making them more likely to break
- Trauma/injury: falls, shaken baby syndrome, acceleration-deceleration injury
What is a haematoma and how do they cause issues?
The collection of blood that forms as a result of a haemorrhage
As damaged bridging veins are under low pressure, the bleeding can be slow causing a delayed inset of symptoms as the haematoma gradually increases in size
What is an acute SD haematoma?
One that causes symptoms within 2 days
What is a subacute SD haematoma?
One that causes symptoms between 3-14 days