Stroke

Question 1

Draw the Circle of Willis and annotate it

Answer 1

Question 2

Outline the blood supply of the brain

Answer 2

Question 3

Cerebrovascular accidents are either:

Answer 3

• Ischaemia or infarction of brain tissue secondary to inadequate blood supply
• Intracranial haemorrhage

Question 4

What are the causes of ischaemic stroke?

Answer 4

Embolism: an embolus originating somewhere else in the body (e.g. the heart) causes obstruction of a cerebral vessel, resulting in hypoperfusion to the area of the brain the vessel supplies.

Thrombosis: a blood clot forms locally within a cerebral vessel (e.g. due to atherosclerotic plaque rupture).

Systemic hypoperfusion: blood supply to the entire brain is reduced secondary to systemic hypotension (e.g. cardiac arrest).

Cerebral venous sinus thrombosis: blood clots form in the veins that drain the brain, resulting in venous congestion and tissue hypoxia

Question 5

In which ways may cerebral blood flow be disrupted?

Answer 5

• Thrombus formation or embolus, for example in patients with atrial fibrillation
• Atherosclerosis
• Shock
• Vasculitis

Question 6

What is a TIA?

Answer 6

transient neurological dysfunction secondary to ischaemia without infarction

Question 7

What is a crescendo TIA?

Answer 7

A crescendo TIA is where there are two or more TIAs within a week. This carries a high risk of developing in to a stroke.

Question 8

How does stroke normally present?

Answer 8

In neurology, suspect a vascular cause where there is a sudden onset of neurological symptoms.

Stoke symptoms are typically asymmetrical:

• Sudden weakness of limbs
• Sudden facial weakness
• Sudden onset dysphasia (speech disturbance)
• Sudden onset visual or sensory loss

Question 9

Outline the risk factors for stroke

Answer 9

• Cardiovascular disease such as angina, myocardial infarction and peripheral vascular disease
• Previous stroke or TIA
• Atrial fibrillation
• Carotid artery disease
• Hypertension
• Diabetes
• Smoking
• Vasculitis
• Thrombophilia
• Combined contraceptive pill

Question 10

What is the ROSIER tool?

Answer 10

Recognition of stroke in emerggency room (ROSIER) is a clinical scoring tool based on clinical features and duration. Stroke is likely if the patient scores anything above 0.

Question 11

Outline some important differential diagnoses of a stroke

Answer 11

• Migraine
• Epilepsy
• Structural brain lesions (SDH, Tumour,
abscess)
• Metabolic/toxic disorders (hypoglycemia)
• Vestibular disorders
• Functional weakness
• Demyelination
• Mononeuropathy

Question 12

What are some important features to delineate within a stroke history?

Answer 12

• Onset
• Course
• Focal vs general symptoms
• “Negative” symptoms (loss of function)

+ risk factors

Question 13

What are 3 important considerations when thinking of thrombolysis?

Answer 13

• Clear time of onset (less than 4 ½ h)
• No contra-indications
• Infarct v haemorrhage

Question 14

How quickly should patients get a CT scan of their brain?

Answer 14

Within 1 hour

Question 15

What indications are there for an urgent scan?

Answer 15

Urgent scan if:
• Thrombolysis or early anticoagulation being considered
• On anticoagulant treatment
• A known bleeding tendency
• Depressed level of consciousness (GCS < 13)
• Unexplained progressive or fluctuating symptoms
• Papilloedema, neck stiffness or fever
• Severe headache at onset

Question 16

How is stroke managed?

Answer 16

• Admit patients to a specialist stroke centre
• Exclude hypoglycaemia
• Immediate CT brain to exclude primary intracerebral haemorrhage
• Aspirin 300mg stat (after the CT) and continued for 2 weeks
• Thrombolysis with alteplase
• Thrombectomy

Question 17

Outline thrombolysis with alteplase

Answer 17

Thrombolysis with alteplase can be used after the CT brain scan has excluded an intracranial haemorrhage. Alteplase is a tissue plasminogen activator that rapidly breaks down clots and can reverse the effects of a stroke if given in time. It is given based on local protocols by an experienced physician. It needs to be given within a defined window of opportunity, for example 4.5 hours. Patients need monitoring for post thrombolysis complications such as intracranial or systemic haemorrhage. This includes using repeated CT scans of the brain.

Question 18

List the absolute and relative contraindications to thrombolysis

Answer 18

Question 19

Outline thrombectomy

Answer 19

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.

Question 20

How is TIA managed?

Answer 20

Start aspirin 300mg daily. Start secondary prevention measures for cardiovascular disease. They should be referred and seen within 24 hours by a stroke specialist.

Question 21

Outline the ABCD2 score

Answer 21

Question 22

Outline the secondary prevention of stroke

Answer 22

• Aspirin 300mg for 2 weeks, then clopidogrel 75 mg (most patients) or warfarin/NOAC if in AF or cardiac origin of embolism
• Atorvastatin 80mg should be started but not immediately (even if cholesterol is “normal”)
• Carotid endarterectomy or stenting in patients with carotid artery disease
• Treat modifiable risk factors such as hypertension and diabetes

Question 23

What specialist imaging is available?

Answer 23

• Diffusion-weighted MRI is the gold standard imaging technique. CT is an alternative.
• Carotid ultrasound can be used to assess for carotid stenosis. Endarterectomy to remove plaques or carotid stenting to widen the lumen should be considered if there is carotid stenosis.

Question 24

How do we delineate whether the right or left cerebral hemisphere has been affected?

Answer 24

1. Crossing of sensory and motor fibres:

• Corticospinal tracts – lower medulla
• Spinothalamic fibres – spinal cord
• Dorsal columns – upper medulla

2. The “dominant hemisphere”:

• Language function localises to left hemisphere
• Awareness of body localises to right hemisphere

3. Visual pathways:

• Monocular vs homonymous deficits
• Cerebellar and cranial nerve lesions
• Result in ipsilateral deficits

Question 25

How do we delineate whether it is the anterior or posterior circulation affected?

Answer 25

Question 26

What are the stroke sub-types? (Bamford classification of stroke)

Answer 26

**Anterior Circulation**: * TACS Total anterior circulation syndrome * PACS Partial anterior circulation syndrome * LACS Lacunar syndrome **Posterior Circulation:** • POCS Posterior circulation syndrome

Question 27

What are the features of a TACS?

Answer 27

*A total anterior circulation stroke (TACS) is a large cortical stroke affecting the areas of the brain supplied by both the **middle** and **anterior cerebral arteries*** **1. New higher cerebral dysfunction:** * Dysphasia * Neglect / visuospatial disorder **2. Hemiparesis / hemisensory loss:** • At least 2 of face / arm / leg **3. Homonymous haemianopia**

Question 28

What are the features of a LACS?

Answer 28

*A lacunar stroke (LACS) is a subcortical stroke that occurs secondary to small vessel disease. **There is no loss of higher cerebral functions** (e.g. dysphasia).* **One of the following:** * Pure motor stroke * Pure sensory stroke * Sensori-motor stroke * Ataxic hemiparesis At least 2 or 3 of face, arm, leg

Question 29

What are the features of a PACS?

Answer 29

*A partial anterior circulation stroke (PACS) is a le**ss severe form of TACS**, in which only part of the anterior circulation has been compromised.* **2 of 3 components of TACS** **Higher disturbance of cerebral function alone** **Restricted motor / sensory loss:** * One limb * Face + hand, but not whole arm

Question 30

What are the features of a POCS?

Answer 30

A posterior circulation syndrome (POCS) involves damage to the area of the brain supplied by the posterior circulation (e.g. **cerebellum** and **brainstem**). • Ipsilateral cranial nerve palsy with contralateral motor/sensory deficit • Bilateral simultaneous motor/sensory loss • Cerebellar dysfunction (e.g. vertigo, nystagmus, ataxia) • Isolated visual field defect (homonymous hemianopia)

Question 31

List the complications of an acute stroke and how these are prevented

Answer 31

1. **Pneumonia:** Swallow assessment, nurse semi-erect, physiotherapy 2. **Dehydration:** IV fluid or NG feeding if oral intake unsafe or inadequate 3. **Hypoxaemia:** Avoid/treat chest infection, treat heart failure 4. **Seizures**: Avoid metabolic disturbance 5. **DVT:** Intermittent pneumatic compression stockings 6. **Pressure sores:** Frequent turning, special mattress, avoid urinary contamination 7. **Urinary infection:** Avoid catheter – use penile sheath 8. **Constipation:** Diet, laxatives 9. **Painful shoulder:** Correct handling, physiotherapy

Question 32

What investigations should be performed to delineate how a stroke happened?

Answer 32

* FBP & ESR * U&E (LFT, CK, TFTs) * Fasting lipids and glucose / HbA1c * ECG * Carotid duplex imaging if anterior circulation * ECHO/Holter – if cardiac embolism suspected\* * CTA/MRA if dissection suspected\* \*consultant request

Question 33

Outline the causes of haemorrhage (age and location)

Answer 33

**According to age:** * \< 45 years Vascular abnormality, e.g. AVM * 45–69 years Small vessel disease * \> 70 years Cerebral amyloid angiopathy **Small vessel disease:** * According to location: * Lobar Amyloid, AVM, small vessel * Deep white Small vessel disease

Question 34

List the two types of primary intracranial haemorrhage

Answer 34

1. Basal ganglia bleed (due to hypertension) 2. Lobar bleed (from cerebral amyloid)

Question 35

What is Albert's test?

Answer 35

* Albert's Test is a screening. tool used to detect the presence of unilateral spatial neglect (USN) in patients with stroke. * 20% due to haemorrhagic stroke * Is essentially drawing lines on a page

Question 36

What is apraxia?

Answer 36

Apraxia is a neurological disorder characterized by the inability to perform learned (familiar) movements on command, even though the command is understood and there is a willingness to perform the movement. Both the desire and the capacity to move are present but the person simply cannot execute the act.

Question 37

What is neglect?

Answer 37

A tendency to ignore spatial surroundings on the opposite side to the cerebral damage

Question 38

What is dysarthria?

Answer 38

Dysarthria is a motor speech disorder in which the muscles that are used to produce speech are damaged, paralyzed, or weakened. The person with dysarthria cannot control their tongue or voice box and may slur words.

Question 39

What is dysphasia?

Answer 39

1. **Expressive dysphasia** is a difficulty in expressing what you want to say. This may be in the form of speech but may also affect their writing and reading aloud abilities. Speech may be non-fluent, and a person may find it difficult to find the right word for something. 2. **Receptive dysphasia** is when a patient has difficulty with the understanding of written or spoken language. Patients can both hear and see the words but not process and make sense of them.

Question 40

Outline, again, the Bamford stroke classification

Answer 40