Midterm - Cerebrovascular System Flashcards
Where do most strokes occur
Arteries, not veins!
When does brain damage become irreversible
Vascular interruption for 4-6 minutes
External carotid artery
Supplies blood to facial muscles, forehead, orbital, oral and nasal cavities
Internal carotid artery
Major source of blood to the brain
Agnosia
Unable to identify or describe things
ACA
Anterior cerebral artery
Supplies surfaces of prefrontal, frontal, and parietal lobes
Above corpus callosum
Symptoms of ACA interruption
Paralysis and sensory loss in legs and feet
Prefrontal lobe symptoms of reduced thinking, reasoning, memory, and impaired planning/executive functioning
MCA
Middle cerebral artery
Supplies blood to entire lateral surfaces including speech language and sensorimotor areas
Symptoms of a MCA interruption
Contralateral hemiplegia (weakness), impaired sensory functions, aphasia, temporal visual spatial deficits, involuntary movements. Hypertension is common cause of bleeding
Cerebrovascular accidents
Sudden development of focal neurological deficits
2 types of cerebrovascular accidents
1) occlusive vascular pathology : thrombosis and embolism
2) hemorrhagic strokes : bleeding from ruptured vessels
Transient ischemic attack
Temporary blood interruptions to brain, resolving in minutes to hour.
Thrombosis
Narrowing of an arterial lumen due to gradual accumulation of lipids, platelets, calcium deposits, and fatty particles in the blood
60% of CVAs
Embolism
Occlusion of smaller artery
Broken plaque away from a thrombus
Occurring during period of activity and awake hours
30% of CVAs
Symptoms - none/possible headaches/seizures
Hemorrhage
Ruptured weak blood vessels
Bleeding under pressure of constant blood flow
Aneurysm or AVM; 10-15% of CVAs
No earning sings, sudden onset of neurological symptoms