10: Cerebrovascular disease Flashcards
ACA- areas supply
- medial surface of the frontal lobe and parietal lobes
- anterior 4-5th of the corpus callosum
- anterior portions of the basal ganglia and internal capsule
- olfactory bulb and tract
Transient Ischemic Attacks
Often resolve before the pt presents to a clinician
Transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia without acute infarction
ACA stroke- sx
Occlusion beyond anterior communicating artery (A2 segment) can produce sx
Contralateral motor and sensory loss mainly in the lower limbs
Gait apraxia (disorder of planning and initiating a skilled movement)
Abulia (delay in verbal and motor response)
Anosmia
Incontinence
Frontal cortical release reflexes: contralateral grasp reflex, sucking reflex
Gegenhalten (paratonic rigidity- toy snake)
MCA- areas supply
- Lateral aspects of frontal, temporal, parietal lobes
- Corona radiata
- Globus pallidus, caudate, putamen
MCA stroke- sx
Contralateral motor and sensory loss (esp upper limb and face)
Contralateral homonymous hemianopia
Eye deviation toward the side of lesion
involving Dominant hemisphere: global aphasia (Broca’s: superior branch, Wernicke’s: inferior branch)
involving non-Dominant hemisphere: anosognosia (neglect of contralateral limbs, dressing difficulty)
PCA- areas supply
- Occipital lobe
- Inferomedial temporal lobe
- Large portion of the thalamus
- Upper brainstem
- Midbrain
PCA stroke (P1: thalamus, sub-thalamus, midbrain)-sx
1: thalamic syndrome: contralateral hemisensory loss with severe burning sensation + chorea
2: Weber’s syndrome: ipsilateral CNIII paralysis + contralateral hemiplegia
3: Claude’s syndrome: ipsilateral CNIII palsy + contralateral ataxia
PCA stroke (P2)- sx
- Contralateral homonymous hemianopia with macular sparing
- Dyslexia (difficulty in reading), Dyscalculia, Visual agnosia (inability to recognize visual objects)
- Transient global amnesia
- Peduncular hallucinosis (bright color may be seen)
Anterior spinal artery occlusion- sx
Medial medullary syndrome or Dejerine syndrome
- Ipsilateral: CNXII- paralysis and atrophy of half tongue
- Contralateral: motor and sensory loss over half of the body
Lateral Medullary syndrome
occlusion of Posterior inferior cerebellar (PICA) or Medullary arteries
- Ipsilateral
1: numbness over face, dysphagia, hoarseness of voice, nystagmus, vertigo, nausea, vomiting (CN V, IX, X)
2: Vertigo, incoordination, dysarthria (cerebellar damage)
3: numbness of arm, body, leg (Gracile and Cuneate nucleus)
4: loss of taste sense (Nucleus/Tract solitarius) - Contralateral: pain + thermal sensation deficit (spinothalamic tract)
Internal carotid artery stroke- sx
Features of MCA occlusion
Contralateral hemiparesis + hemisensory loss
Amaurosis Fugax (repeated transient monocular visual loss): warning sign of the lesion
Unilateral frontal headache
High pitch carotid bruit at the angle of the jaw
Complete Basilar artery occlusion- sx
Supplies pons and cerebellum
- Quadriplegia
- Multiple CN involvement (V, VI, VII, VIII)
- Cerebellar dysfunction: vertigo, dysarthria, incoordination
Small vessel (Lacunar) stroke- sx
1: Pure motor hemiperesis- posterior lobe of internal capsule (arm, leg, face**)
2: Pure sensory stroke- ventral posterolateral thalamus (VPL)
3: Pure motor hemiperesis with motor aphasia- genu and anterior limb of internal capsule + corona radiata
4: Ataxic hemiperesis- base of pons
Imaging
CT: Hemorrhage
MRI: Ischemia (within 45 mins of the onset)
Angiography: ‘gold standard’ for stroke*
Acute interventions in Stroke
*Thrombolysis using recombinant tissue plasminogen activator (r-TPA) for ischemic stroke: 0.9mg/kg (10% bolus and rest 90% in infusion 60mins)- (should start within 3hrs of onset)
Aspirin (within 48hrs-> reduced mortality)
Heparin (within 14days: risk of hemorrhagic stroke)
-stroke due to cerebral vasculitis: Steroids
-Mechanical thrombolysis: Concentric retriever (grasping device), Penumbra device (aspiration to remove clots)
