1. Dr. Meg-angela Christi M. Amores
Stroke Syndromes
Dr. Meg-angela Christi M. Amores

2. Cerebrovascular Disease
ischemic stroke
hemorrhagic stroke
cerebrovascular anomalies such as intracranial aneurysms and arteriovenous malformations (AVMs)
Incidence increases with age

3. Stroke
Most strokes manifest by the abrupt onset of a focal neurologic deficit
Like patients were “struck by the hand of God”
Definition:
abrupt onset of a neurologic deficit that is attributable to a focal vascular cause

4. Definition of terms Thrombosis: inappropriate clotting
Embolism: migration of clots
Ischemia: loss of blood supply in a tissue due to impeded arterial flow or reduced venous drainage
Infarction: cell death

5. Definition of Terms
Cerebral ischemia is caused by a reduction in blood flow that lasts longer than several seconds
infarction - death of brain tissue
transient ischemic attack (TIA) - all neurologic signs and symptoms resolve within 24 h regardless of whether there is imaging evidence of new permanent brain injury

6. Hemorrhagic Stroke
Bleeding into subdural and epidural spaces is principally produced by trauma
SAHs are produced by trauma and rupture of intracranial aneurysms
Hemorrhage are classified by location
Often identified by CT scan

8. Ischemic Stroke
Acute occlusion of an intracranial vessel causing reduction in blood flow to the brain region
INFARCTION results when:
Cerebral blood flow of 0 (zero) in 4 – 10 mins
CBF <16-18 ml/ 100g tissue per min in 1 hour
CBF <20ml/100g tissue per min = ischemia

9. Causes of Ischemic Stroke

10. Causes of Ischemic Stroke
30% of strokes remain unexplained despite extensive evaluation
establishing a cause is essential in reducing the risk of recurrence
Focus on: atrial fibrillation and carotid atherosclerosis
20% of all ischemic strokes is CARDIOEMBOLIC

11. Causes of Ischemic Stroke

12. Cardioembolic Stroke 20% of all ischemic strokes
embolism of thrombotic material forming on the atrial or ventricular wall or the left heart valves
thrombi then detach and embolize into the arterial circulation
Embolic strokes tend to be sudden in onset, with maximum neurologic deficit at once

13. Cardioembolic Stroke causes:
nonrheumatic atrial fibrillation MI
prosthetic valves
rheumatic heart disease
ischemic cardiomyopathy

14. Carotid Atherosclerosis
10% of all ischemic strokes
frequently within the common carotid bifurcation and proximal internal carotid artery
RISK FACTORS:
Male gender, older age, smoking, hypertension, diabetes, and hypercholesterolemia

15. Causes of Ischemic Stroke

16. Other causes of stroke Intracranial Atherosclerosis
Dissection of Internal Carotid Artery
Hypercoagulability
Venous sinous thrombosis
Fibromuscular dysplasia
Vasculitis

17. Approach to patient
Once the diagnosis of stroke is made, a brain imaging study is necessary to determine if the cause of stroke is ischemia or hemorrhage
CT imaging of the brain is the standard imaging modality to detect the presence or absence of intracranial hemorrhage
If bleeding is ruled out, do thrombolysis
Medical management to reduce the risk of complications becomes the next priority

18. STROKE SYNDROMES

19. Middle Cerebral Artery

20. Middle Cerebral Artery
entire MCA is occluded at its origin :
contralateral hemiplegia, hemianesthesia, homonymous hemianopia, and a day or two of gaze preference to the ipsilateral side
Dysarthria is common because of facial weakness
global aphasia
anosognosia, constructional apraxia, and neglect

21. to be continued