Lecture 5: Cerebral Stroke Syndromes Flashcards
What two major arteries supply the brain with blood flow?
- internal carotid
2. Vertebral
What two major cerebral arteries come off of the internal carotid?
- anterior cerebral
2. middle cerebral
What major cerebral arteries come off of the vertebral?
Posterior cerebral artery from the basilar
What area of the brain does the ACA supply?
medial frontal and parietal lobes
What area of the brain does the MCA supply?
lateral frontal, parietal, temporal lobes
What areas of the brain does the PCA supply?
occipital lobe, medial and inferior temporal lobe, cerebellum, brainstem
What is ACA syndrome?
very uncommon, 3 % of strokes with clinical features of:
contralateral hemiplegia and hemianesthesia LE more than UE
Albulia- lack of will or initiative (prefrontal cortex)
Apraxia
L ACA will cause aphasia (SMA)
What is apraxia?
problems with motor planning and sequence
loss of connection between verbal and motor areas of the brain
What are the 5 different types of apraxia?
- ideomotor
- ideational
- Constructional
- Gait
- Verbal
What is an ideomotor apraxia?
damage in the left parietal lobe
inability to carry out a verbal motor command
What is ideational apraxia?
damage to bilateral parietal lobe
inability to create a plan for multistep movement plans
What is constructional apraxia?
damage usually in right parietal lobe
inability to draw pictures or construct simple configurations
What is gait apraxia?
damage in the frontal lobes
impaired gait but motor and sensory function intact
How can you differentiate between gait ataxia and apraxia?
compare cerebellar functions as ataxia will be from damaged of cerebellum
What is the most common site of occlusion in brain?
MCA as there is less collateral flow around it
the more proximal the occlusion the more damage
What are clinical features of a MCA occlusion?
CL hemiplegia UE then face then LE
- homonymous hemianopsia
- CL sensory loss usually UE
What other clinical features are also likely if damage is to dominate hemisphere?
typically left, then aphasia
What other clinical features are also likely if damage is to non-dominate hemisphere?
agnosia (can’t process sensory info), unilateral neglect, apraxia
What is homonymous hemianopsia?
loss of half of the field of view on the same side in both eyes because visual pathways are supplied by MCA
What is unilateral neglect?
inability to report, respond, or orient to stimuli in the CL space this is not due to sensory or motor deficits
Why does this unilateral neglect occur?
not well understood usually damage to R parietal lesion which will affect L side