TIA

Question 1

Definition

Answer 1

Acute loss of neurological fn./monocular vision caused by ischaemia w Sx. <24h.

*occurs in 10% prior to developing stroke

Question 2

CLINICAL FEATURES

• rapid onset(seconds-mins) w variable resolution up to 24h.
  1. Ant. circulation
  2. Post. circulation
  3. Both
  4. Hx. of risk f.
  5. Neuro exam
  6. CV system

Answer 2

1. amaurosis fugax(monocular), aphasia/dyslexia/dysgraphia
2. Homonymous visual field loss, dysarthria, combined brain stem Sx.(vertigo, diplopia, dysphagia), bilat. weakness/sensory loss
3. unilat. weakness => face/arm/leg in isolation/combination; unilat. sensory loss => face/arm/leg in isolation/combination.
4. COCP in young women(2-3x)
5. Usually unremarkable
6. Cholesterol embolus on fundoscopy, arrhythmia, hypert. retinal changes, hypert., murmur, signs of cardiac failure, loss of peripheral pulses & bruits.
   * rarely leads to LOC.

Question 3

DDx:

1. Migraine
2. Partial seizure
3. transient global amnesia
4. Intracranial lesions
5. Metab. changes
6. Peripheral n. lesions

Answer 3

1. slower onset(15-30 mins), assoc. positive Sx ie flashing lights/tingling and migrainous headache
2. shorter duration(sec-mins), stereotyped when recur.
3. anterograde amnesia lasting hours w norm. physical fn.
4. usually progressive deficits w intermittent Sx.
5. Hypoglycemia=> transient neurological deficits
6. Carpal Tunnel Syndrome

Question 4

INVESTIGATIONS

1. Risk f. for vascular disease
2. Source of embolism
3. Thrombotic tendencies
4. Infalm. vasc disease
5. When DDx includes intracranial lesion/partial seizures
6. DDx w partial seizures

Answer 4

1. BP, blood tests: glucose, cholesterol, TFT
2. ECG, echo, blood cultures, 24h tape, carotid Doppler, angiography/MR angiography
3. Blood tests: FBC, thrombophilia screen(includes lupus anticoaguluant), Sickle cell screen(all pts at risk)
4. Blood tests: ESR, ANA, anticardiolipin, syphilis serology
5. Head CT/MRI
6. EEG can be helpful

Question 5

Primary Prevention of Strokes & TIAs

Answer 5

1. Control atheroma risk f.
   - Controlling hypert. reduces risk by 40%

*86 pts w asymptomatic carotid stenosis need op to prev 1 stroke

Question 6

Secondary Prevention of Strokes &TIAs:

1. Control risk f.
2. Long term antithrombotic tx.
3. Anticoagulation
4. Carotid stenosis

Answer 6

1. Hypert, diabetes, smoking, alcohol, hypercholesterolaemia
   - most end up on diuretic, ACE-i and statin
2. After aspirin for 2w after onset of Sx, Clopidogrel 75mg(recommended first-line) OR MR Dipyridamole 200 mg + Aspirin 75mg(if clopidogrel intolerant) OR dipyridamole alone(if clopidogrel and aspirin intolerant) OR aspirin alone(if clopidogrel and dipyridamole intolerant)
3. In AF pts, risk reduced frm 12% to 4% per year. Maintain INR 2-3
4. Reduced risk when stenosis >70%, esp when >80%.
   - Angioplasty/endarterectomy
   - Carotid artery endarterectomy recommened if stroke/TIA in carotid territory & not severely disabled. only considered if carotid stenosis >70% according to ECST criteria.

Question 7

ABCD2 prognostic scores:

Answer 7

Age >= 60y (1pt)
BP >= 140/90 (1pt)
Clinical features
- Unilat weakness(2pts)
- Speech disturbance, no weakness(1pt)
Duration of Sx
- >60 mins(2pts)
- 10-59 mins(1pt)
Diabetes(1pt)

ABCD2 >=4 hv higher risk of stroke hence:

• aspirin 300 mg
• specialist assessment and inv within 24h of onset
• measures for secondary prev and discuss risk f.

ABCD <= 3

• aspirin 300 mg
• specialist assessment within 1w onset, decide on brain imaging (if vasc territory/pathology uncertain)

*if crescendo TIA(>=2 episodes/week), tx as high risk of stroke