stroke/case 5 Flashcards
(39 cards)
What does the brain use for respiration? what type of respiration?
O2 and glucose
aerobic respiration: no lactate build up
What happens with occlusion of the anterior cerebral artery?
- contralateral hemiparesis
- sensory loss of contralateral leg and perineum
What parts of the brain does the middle cerebral artery supply?
- lateral sulcus and travels along lateral surface of frontal, temporal and parietal lobes
- subcortical areas including internal capsule and neostratium
What happens with occlusion of the middle cerebral artery?
- contralateral hemiparesis
- sensory loss of contralateral upper limb
- contralateral homonymous hemianopia
- aphasia
What happens with occlusion of the posterior cerebral artery?
-contralateral homonymous hemianopia with macular sparing
-visual agnosia
(-Weber’s syndrome: branches of the PCA that supply midbrain: ipsilateral CN3 palsy + contralateral weakness of upper and lower extremity)
What parts of the brain does the posterior cerebral artery supply?
curves around midbrain to reach medial surface of cerebral hemisphere
–> inferior surface of temporal lobe + occipital lobe
What happens with occlusion of the basilar artery?
- ‘locked-in’ syndrome
- respiratory failure: death
What is a lacunar stroke?
type of ischemic stroke that occurs when blood flow to one of the small arteries deep within the brain
What are symptoms of lacunar strokes?
What are the risk factors?
Common sites?
- isolated hemiparesis, hemisensory loss or hemiparesis with limb ataxia
- strong association with hypertension
- common sites: basal ganglia, thalamus and internal capsule
What are functional consequences of damage to motor cortex?
movement
What are functional consequences of damage to frontal lobe?
-Broca’s aphasia
-disinhibition
-perseveration
-anosmia
-inability to generate a list
(judgement, foresight, voluntary movement, smell)
What are functional consequences of damage to temporal lobe?
- Wernicke’s aphasia
- superior homonymous quadrantonopia
- auditory agnosia
- prosopagnosia
What are functional consequences of damage to brainstem?
swallowing, breathing, heartbeat, wakefulness centre (+other involuntary functions)
What are functional consequences of damage to cerebellum?
- midline lesions: gait and truncal ataxia
- hemisphere lesions: intention tremor, past pointing, dysdiadokinesis, nystagmus
What are functional consequences of damage to parietal lobe?
- sensory inattention
- apraxias
- astereognosis (tactile agnosia)
- inferior homonymous quadrantanopia
- Gerstmann’s syndrome (lesion of dominant parietal): alexia, acalculia, finger agnosia and rich/left disorientation)
What are functional consequences of damage to occipital lobe?
- homonymous hemianopia (with macular sparing)
- cortical blindness
- visual agnosia
What brain areas do the anterior cerebral artery supply?
superior and medial surfaces of frontal and parietal lobes
What is the WHO definition of stroke?
-sudden onset of acute focal ‘occasionally global) neurological deficit probably due to a pathological process in blood vessels
What are stroke risk factors?
- BP (especially in haemorrhage strokes)
- cholesterol
- blood sugar/diabetes
- atrial fibrillation
- obesity
- smoking
What is the FAST test?
Face
Arms
Speech
Time
What is the percentage of ischemic strokes compared to haemorrhage strokes
85%
15%
What are causes of ischemic strokes?
- blood clot causing occlusion: carotid atherosclerosis (carotid bifurcation), embolism of plate rich clot further i cerebral vessel
- atrial fibrillation
What must be looked at in terms of blood diffusion:perfusion for treatment via thrombolysis?
it mismatch (perfusion loss but not much diffusion loss) then brain tissue can be salvaged
What is the neurovascular unit and what does it consist of?
- close interaction of brain cells with the brain endothelium and the extracellular matrix contributes to the maintenance of brain homeostasis and functions
- consists of :
- ->astrocytes, microglia, neurones
- -> endothelial cells and pericytes
- -> extracellular matrix
