Post on 13-Jan-2020
Stroke- Definition
“ Rapidly developing clinical neurological signs of focal (or global) disturbance of cerebral function, with symptoms lasting 24 hours or longer or leading to death, with no apparent cause other than of vascular origin”
Stroke and Stroke Mimics
• Other disease mimicking stroke = Stroke Mimic
• Stroke mimicking other disease = Stroke Chameleon
• Important in diagnosis- Time is brain
• Thrombolysis and thrombectomy- potent treatment modality
Importance of Rapid and Accurate Recognition
• Early thrombolysis- NINDS, ECASS II
• Potential thrombectomy- MR CLEAN, DAWN
• Early intervention for secondary prevention
– EXPRESS Trial, SOS-TIA trial
• “Fast” compromising “accuracy”?
• Correct diagnosis- more appropriate treatment. Stroke vs Stroke Mimics
Stroke and Stroke Mimics
• Accuracy important in stroke diagnosis
• Ambulance,primary care, ED, Stroke team
• Joint effort
Meta-analysis of thrombolysed stroke mimics Less bleeding in stroke mimics (But unnecessary) Fast vs Accurate
Stroke and Stroke Mimics: Case 1
• 61 years old man; underlying Hpt & DM
• Sudden right sided hemiparesis 1hr onset
• Dysphasia, right hemineglect, hemianopia
• NIHSS 15
• Brain CT
Stroke and Stroke Mimics: Case 1
• Acute onset localising features- Left MCA
• Normal brain CT despite moderate clinical stroke severity
• Thrombolysis
• Thrombectomy-proximal occlusion
Failure to
Thrombolyse*
Complications
of tPA
90
60
30
%
Medico-legal Considerations with Intravenous
Tissue Plasminogen Activator in Stroke
95%
*Failure to diagnose, failure to transfer to an institution where
thrombolysis can be given, delay in evaluating pt, failure to recommend
tPA as a treatment
5%
plaintiff-favoured verdicts
30%
Stroke Research and Treatment 2013
Stroke Mimics
• Stroke mimics- 20-30%
• CT scan may likely be normal and patient may be thrombolysed even in stroke mimics
• Brain imaging (CT/MRI) may not be helpful differentiating stroke with mimics
• Standard diagnosis- history, hard signs, and supported by imaging (which may be normal)
• Seizures
• Syncope
• Sepsis
• Sugar
• Space Occupying
Lesion
• pSychogenic
• Sakit Kepala
• OtherS- Bell’s palsy,
periph vertigo, etc.
Stroke Mimics Causes
• Progressive onset • Signs inconsistent
with symptoms • Confusion/loss of
consciousness • Seizure at onset • Cognitive
impairment • No lateralising or
focal features
Features Favouring stroke mimics
Stroke Mimics and Age
Vroomen et al JSCVD 2008
• Younger age group- Higher percentage of conversion disorder and migraine as mimics
Case 2
• 65 years old man; underlying hypertension
• Previous stroke 2 years; right hemiparesis recovered fully
• Presenting with GTC seizures.
• Noticed dense left hemiparesis and confusion.
• NIHSS 8
Stroke and Stroke Mimics
• Red flags:
– Confusion
– Seizure at onset
– Strong association to cause of seizure
• ?Eligible for thrombolysis based on clinical (NIHSS) and radiological (Brain CT) features
• ?MRI prior thrombolysis
Seizure Mimicking Stroke
• 20% of stroke mimics
• More apparent if has history of recurrent seizures stereotyped semiology
• Post stroke seizures occur late > 6 months
• Brain CT may be misinterpreted as an acute infarct corresponding to paralysis
• Todd’s paralysis- difficult to differentiate from acute stroke
Todd’s Paralysis
• 15% of seizures.
• Most common after GTC especially after clonic activity
• Usually causes hemiparesis/hemiplegia
• Can be associated with aphasia, sensory loss or visual field defect (uncommon)
• Usually lasts minutes but can last hours or even days.
Case 3
• 69 years old man
• Underlying DM/Hpt/CL
• Left hemiparesis on awakening from sleep
• Dysphasia and Confusion
• NIHSS 10
• BG 1.5 mmol/l
Case 3 • Wake-up “stroke”
• Red flags: – Features inconsistent with localisation; left
hemiparesis with dysphasia
– Hypoglycaemia
– Confusion not accompanied by other hemispheric features
• Improve on correction of hypoglycaemia
• MRI- Highly sensitive and specific for acute ischaemic stroke changes
• CT may be normal despite an actual stroke
Migraine Mimicking Stroke
• Familial hemiplegic migraine – Autosomal dominant – Young females
• Other neurological deficits – Focal weakness – Hemianopia – Dysphasia
• Recurring stereotypes • Headaches may not be a prominent
feature
Functional Disorder Mimicking Stroke
• Acute weakness/sensory disturbances
• Inconsistent deficits
• Non-localising
• Positive psychogenic signs eg. Using agonist-antagonist muscle or Hoover’s sign- more important than normal MRI
• Secondary gain, La Belle Indifference
Case 4
• 57 years old woman
• Underlying Hpt
• Left LMN VII CN palsy
• On awakening
• Confusion
• Normal brain CT
• ?Bell’s palsy
Case 4
• Red flag: Confusion
• MRI acute stroke
• Brain stem involvement
• Posterior circulation may not be typical presentation
• Stroke chameleon
Conclusions
• History and examination- Important in diagnosing stroke and identifying stroke mimics
• Red flags- help in differentiating stroke mimics, improving diagnostic accuracy
• Brain imaging – assisting diagnosis
• MRI preferred for acute stroke changes
• Identifying mimics- Crucial step in acute stroke management. Facilitating thrombolysis and thrombectomy and avoiding unnecessary Rx
• Hospital Pengajar UPM • Stroke dedicated ER • Regional Emergency
Stroke Quick-response (RESQ) Strategy
• High volume stroke centre with T & T
www.strokeresq.com Facebook: www.facebook.com/strokeresq • Thrombolysis &
Thrombectomy workshop, hands-on and simulation