Anterior Cerebral Artery (ACA)
branches off the internal carotid artery and supplies the frontal and parietal lobes
ACA Occlusion site for CVA
- Usually presens w/ greater involvement of the LE than UE or face
- Extensive frontal lobe infarction produces significat behavioral changes
- Right-sided damage to the frontal lobe may cause contralateral neglect
- Damage to the supplementary motor area may produce aphasia
- Lesions of the ACA are uncommon
Middle Cerebral Artery (MCA)
branches off th internal carotid artery and supplies the lateral aspect of the cerebral hemispher(frontal, temporal and parietal lobes)
MCA Occlusion site for CVA
- Most common site of stroke
- Occlusion results in drowsiness, contralateral hemiplegia, and cortical sensory loss of the face, arm, and leg w/ the face and arm more involved than the leg
- Homonymous hemianopsia (visual field defect) and deviation of the eyes away form hemiplegic side also result
- Broca's aphasia (expressive dysfunction ) results from occlusion of the MCA affection the lwoer frontal cortex.
- Wernicke's Aphasia (recpetive dysfunction) may also result from temporal lesions
- Pts exhibiting global aphasia (involves both Broaca's and Wernicke's areas) have severe expressive and receptive language dysfunction.
- Apraxia, a disorder of voluntary learned movement, is also common.
- Infarction of the non-dominant right hemisphere typically produces a flat or expressionless affect
Posterior Cerebral Artery (PCA)
arises fdorm the basilar artery, and supplies the corresponding occipital, medial and inferior temporal lobe.
PCA Occlusion site for CVA
- Occlusion of thalamic branches (affecting pain and temperature the most) and persistent contralateral pain in respose to any type of sensory input.
- Proprioception is severly involved.
- Right-sided infarcts produce hemianopsia, and left-side infarcts produce alexia (word blindness) and anomia (word-finding difficulty).
During the early stages of stroke
- flaccidity w/ no voluntary movement is common.
- Flaccidity is usually present immediately after the stroek and is generally short-lived, lasting hours, days or weeks.
flaccidity is usually replaced by
development of spasticity and mass patters of movement, termed synergy's
Spasticity emerges in about ___ of cases.
Muscles involved in synergy patterns are often
so strongly linked together that isolate dmovments outside the mass movment patterns are not possible
As recovery progresses...
spasticity begin to declien and advanced movement pattersn become possible