Stroke

Question 1

Definition of stroke?

Answer 1

Rapid onset, focal neurological deficit due to a vascular lesion lasting >24h

Question 2

Pathogenesis of stroke

Answer 2

• Infarction due ischaemia (80%)

- intracerebral haemorrhage (20%).

Question 3

Causes of ischaemic strokes?

Answer 3

I. Atheroma
- Large (e.g. MCA)
- Small vessel perforators (lacunar)
II. Embolism
- Cardiac (30% of strokes):AF, endocarditis, MI
- Atherothromboembolism: e.g. from carotids

Question 4

Causes of haemorrhagic stroke?

Answer 4

• ↑BP
• Trauma
• Aneurysm rupture
• Anticoagulation
• Thrombolysis

Question 5

Watershed stroke

Answer 5

sudden ↓ in BP (e.g. in sepsis)

Question 6

Risk factors for stroke?

Answer 6

1. IHD RFs: ↑BP, Smoking, DM, ↑ lipids
2. Cardiac: AF, valve disease
3. Peripheral vascular disease
4. ↑ PCV/Hct
5. OCP

Question 7

Which ethnicity is more prone to strokes?

Answer 7

↑ in Blacks and Asians

Question 8

Overview of Oxford (/Bamford) classification of stroke?

Answer 8

• Based on clinical localisation of infarct
• S=syndrome: prior to imaging
• I=infarct: after imaging when atheroembolic infarct
  confirmed

Question 9

4 oxford classifications of stroke?

Answer 9

TACS- Total Anterior Circulation Stroke
PACS- Partial Anterior Circulation Stroke
POCS- Posterior Circulation Stroke
LACS- Lacunar Stroke

Question 10

TACS stroke: mortality?

Answer 10

Highest mortality (60% @ 1yr) + poor independence

Question 11

Site of TACS stroke?

Answer 11

Large infarct in carotid / MCA, ACA territory

Question 12

Signs of TACS stroke?

Answer 12

All 3 of:

1. Hemiparesis (contralateral) and/or sensory deficit (≥2 of face, arm and leg)
2. Homonymous hemianopia (contralateral)
3. Higher cortical dysfunction
   - Dominant (L usually): dysphasia
   - Non-dominant: hemispatial neglect

Question 13

PACS stroke site?

Answer 13

Carotid / MCA and ACA territory

Question 14

PACS stroke signs?

Answer 14

2/3 of TACS criteria, usually:

1. Hemiparesis (contralateral) and/or sensory deficit (≥2 of face, arm and leg)
2. Higher cortical dysfunction
   - Dominant: dysphasia
   - Non-dom: neglect, constructional apraxia

Question 15

constructional apraxia

Answer 15

an inability or difficulty to build, assemble, or draw objects.

Question 16

Site of POCS stroke?

Answer 16

Infarct in vertebrobasilar territory

Question 17

Signs of POCS stroke?

Answer 17

Any of

1. Cerebellar syndrome (DANISH P)
2. Brainstem syndrome
3. Contralateral homonymous hemianopia

Question 18

Site of LACS stroke?

Answer 18

• basal ganglia
• internal capsule
• thalamus
• pons

Question 19

Absence of which signs makes the diagnosis LACS stroke more likely?

Answer 19

Absence of

• Higher cortical dysfunction
• Homonymous hemianopia
• Drowsiness
• Brainstem signs

Question 20

Potential syndromes of LACS?

Answer 20

1. Pure motor: posterior limb of internal capsule (Commonest)
2. Pure sensory: posterior thalamus (VPL)
3. Mixed sensorimotor: internal capsule
4. Dysarthria (slurred speech) / clumsy hand
5. Ataxic hemiparesis: ant. limb of internal capsule
   - Weakness + dysmetria

Question 21

Dysmetria

Answer 21

• a lack of coordination of movement

- eg dysdiadochokinesis

Question 22

Signs of brainstem infarct?

Answer 22

Complex signs depending on relationship of infarct to CN nuclei, long tracts and brainstem connections
eg
- facial weakness with CN7 infarct
- Nystagmus and vertigo with CN8, - Horner’s syndrome with sympathetic fibres infarct

Question 23

Site of lateral medullary syndrome ( Wallenberg Syndrome)

Answer 23

PICA or vertebral artery territory

Question 24

Features of lateral medullary syndrome ( Wallenberg Syndrome)

Answer 24

DANVAH

• Dysphagia
• Ataxia (ipsilateral)
• Nystagmus (ipsilateral)
• Vertigo
• Anaesthesia (Ipsilateral facial numbness, Contralateral pain loss)
• Horner’s syndrome (ipsilateral)

Question 25

Locked-in Syndrome features?

Answer 25

Pt. is aware and cognitively intact but completely paralysed except for the eye muscles.

Question 26

Locked-in Syndrome causes?

Answer 26

- Ventral pons infarction: basilar artery - Central potine myelinolysis: rapid correction of hyponatraemia

Question 27

Overview of Acute management of stroke?

Answer 27

1. Resus (NBM) 2. Monitor 3. Imaging 4. Medical 5. Surgery

Question 28

Monitoring of acute stroke?

Answer 28

1. Glucose: 4-11mM: sliding scale if DM 2. BP: <185/110 for thrombolysis (Rx of HTN can → ↓ cerebral perfusion)

Question 29

Imaging of acute stroke?

Answer 29

Urgent CT/MRI I. Diffusion-weighted MRI is most sensitive for acute infarct II. CT will exclude primary haemorrhage

Question 30

Medical management of acute stroke?

Answer 30

I. Thrombolysis II. Aspirin 300mg PO/PR once haemorrhagic stroke excluded ± PPI (If CI, give Clopidogrel instead)

Question 31

Thrombolysis for stroke?

Answer 31

- Consider if 18-80yrs and <4.5hrs since onset of symptoms - Alteplase (rh-tPA) - → ↓ death and dependency - CT 24h post-thrombolysis to look for haemorrhage

Question 32

Surgical management for stroke?

Answer 32

- May coil bleeding aneurysms | - Decompressive hemicraniectomy for some forms of MCA infarction.

Question 33

Primary prevention of stroke (before)?

Answer 33

- Control RFs: (HTN, ↑ lipids, DM, smoking, cardiac disease) - Consider life-long anticoagulation in AF (use CHADS2) - Carotid endarterectomy if symptomatic with 70% stenosis - Exercise

Question 34

Secondary prevention of stroke (after)?

Answer 34

I. Start a statin after 48h II. Aspirin / clopi 300mg for 2wks after stroke then either a. Clopidogrel 75mg OD (preferred option) b. Aspirin 75mg OD + dipyridamole MR 200mg BD III. Warfarin instead of aspirin/clopi if Cardioembolic stroke or chronic AF b. Start from 2wks post-stroke (INR 2-3) IV. Carotid endarterectomy if good recovery + ipsilat stenosis ≥70%

Question 35

Rehabilitation for stroke?

Answer 35

MENDS I. MDT: SALT (Speech and Lang Therapist) , dietician, OT, PT II. Eating a. Screen swallowing: refer to specialist b. Screen for malnutrition III. Neurorehab: physio and speech therapy IV. DVT Prophylaxis V. Sores: must be avoided @ all costs

Question 36

PACS stroke mortality?

Answer 36

- 20% mortality at 1 year | - 33% independent at 1 yr