Definition of Stroke
•A stroke or Cerebrovascular accidents is defined by abrupt
onset of a neurological deficit that is attributable to a focal
vascular cause.
•Stroke is the third most common cause of death in the
developed world after cancer and ischaemic heart disease,
and is the most common cause of severe physical disability.
References : Harrison 18
th
ed
Stroke types
•Stroke is classified into two major types:
1.Ischemic stroke: Brain ischemia due to thrombosis,
embolism, or systemic hypoperfusion
2.Hemorrhagic stroke: Brain hemorrhage due to
intracerebral hemorrhage or subarachnoid hemorrhage.
•Approximately 80 % of strokes are due to ischemic cerebral
infarction and 20 % to brain hemorrhage.
Stroke types ?
BRAIN ISCHEMIA 1
•Thrombosis generally refers to local in situ obstruction of an artery.
•Embolism refers to particles of debris originating elsewhere that block
arterial access to a particular brain region .
•Systemic hypoperfusion is a more general circulatory problem,
manifesting itself in the brain and perhaps other organs.
•References 1: Caplan LR. Basic pathology, anatomy, and pathophysiology of stroke. In: Caplan's Stroke:
A Clinical Approach, 4th ed, Saunders Elsevier, Philadelphia 2009. p.22.
Hemorrhagic stroke
Hemorrhagic stroke: types
1.Intracerebral hemorrhage refers to bleeding directly into
the brain parenchyma
2.Subarachnoid hemorrhage refers to bleeding into the
cerebrospinal fluid within the subarachnoid space that
surrounds the brain
•Note: Hemorrhage is characterized by too much blood
within the closed cranial cavity, while ischemia is
characterized by too little blood to supply an adequate
amount of oxygen and nutrients to a part of the brain.1
• Reference 1: Caplan LR. Intracranial branch atheromatous disease: a neglected, understudied, and
underused concept. Neurology 1989; 39:1246.
Diagnosis ?
•Clinical
•Investigation
Clinical ?
•Is there any neurological deficit ?
•Is there any risk factor for vascular disease ?
STROKE RISK FACTORS
•Age
•Gender (male > female)
•Race (Afro-Caribbean > Asian > European)
•Heredity
•Previous vascular event, e.g. MI, stroke or
peripheral embolism
•High fibrinogen
•Cerebral infarction is mostly due to
thromboembolic disease secondary to
atherosclerosis in the major extracranial
arteries (carotid artery and aortic arch).
•About 20% of infarctions are due to embolism
from the heart, and a further 20% are due to
intrinsic disease of small perforating vessels
(lenticulostriate arteries), producing so-called
'lacunar' infarctions.
Hemorrhagic stroke : Risk Factor
Cincinnati Prehospital Stroke Scale
1. Facial droop: Have the person smile or show his or her teeth.
•Normal: Both sides of face move equally
•Abnormal: One side of face does not move as well as the other (or at all)
2. Arm drift:
•Normal: Both arms move equally or not at all
•Abnormal: One arm does not move, or one arm drifts down compared with the
other side
3. Speech:
•Normal: Patient uses correct words with no slurring
•Abnormal: Slurred or inappropriate words or mute
Patients with 1 of these 3 findings as a new event have a 72% probability of an
ischemic stroke. If all 3 findings are present the probability of an acute stroke is
more than 85%
Hurwitz AS, Brice JH, Overby BA, Evenson KR (2005). "Directed use of the Cincinnati Prehospital Stroke Scale by laypersons". Prehosp Emerg Care 9 (3): 292–6
Investigations ?
•Imaging
7 questions ?
1. Is this a vascular lesion ?
CT/MRI
CT HEAD
•Imaging
7 questions ?
2. Is it ischaemic or haemorrhagic?
CT/MRI
7 questions ?
3. Is it a subarachnoid haemorrhage?
CT/MRI
SubArachnoid Hemorrhage
7 questions ?
4. Is there any cardiac source of embolism?
ECG/ECHO
ECG: Afib
7 questions ?
5. What is the underlying vascular disease?
•Duplex ultrasound of carotids
•Magnetic resonance angiography(MRA)
•CT angiography (CTA)
•Contrast angiography
7 questions ?
6. What are the risk factors?
Full blood count
Cholesterol
Blood glucose
7 questions ?
7. Is there an unusual cause?
Rule out Bleeding Disorders/
ESR