Cerebrovascular Disease Flashcards
What are the four main causes of global cerebral ischemia?
Low perfusion
Acute decrease in blood flow
Chronic hypoxia
Repeated episodes of hypoglycemia from insulinoma
What is cerebrovascular disease and what are the two main causes?
Neurologic deficit due to cerebrovascular compromise. 85% due to ischemia and 15% due to hemorrhage
Which type of global cerebral ischemia results in transient confusion with prompt recovery?
Mild global ischemia
Which type of global cerebral ischemia results in diffuse necrosis or vegetative state?
Severe global ischemia
What areas are damaged by moderate global ischemia?
- pyramidal neurons of the cerebral cortex (layers 3,5 and 6) which leads to laminar necrosis
- pyramidal neurons of the hippocampus (temporal lobe) which affects long term memory
- purkinjie layer of the cerebellum which integrates sensory perception with motor control
What is the difference between regional ischemia and transient ischemial attack?
Focal neurologic deficits due to regional ischemia to the brain. tIA is symptoms last less than 24 hours and ischemic stroke if more than 24 hours
What causes thrombotic stroke? Where does the causative agent develop? What is seen on cross section?
Due to rupture of an atherosclerotic plaque which develops at branch points of vessels. Results in a pale infarct at the periphery of the cortex.
What is the most common source of emboli? Which vessel is involved. What is seen on cross section?
Common source is left side of the heart due to atrial fibrillation. Middle cerebral artery. Results in a hemorrhagic infarct at the periphery of the cortex.
What causes LACUNAR stroke? Which vessels are involved? What causes a pure motor stroke? A pure sensory stroke?
Occurs secondary to hyaline arteriosclerosis, a complication of hypertension.
Involvement of internal capsule leads to pure motor stroke
Involvement of thalamus leads to pure sensory stroke
What does ischemic stroke lead to? What is seen after 12 hours? 24 hours? Days 1-3? Days 4-7? Weeks 2-3? What do these result in?
Liquefactive necrosis.
Red neurons due to eosinophilic change in the cytoplasm of neurons
Necrosis
Neutrophil infiltration
Microglial cell infiltration
Gliosis which results in a fluid filled cystic space
A patient presents with headache, nausea, vomiting and eventual coma. What does he have? What caused it?Which structures were involved? What is the common site?
He has intra cerebral hemorrhage which is bleeding into the brain parenchyma. Classically due to rupture of Charcot- Bouchard micro aneurysms of the lenticulostriate vessels. Basal ganglia is the most common site. This is due to a complication of hypertension.
A patient presents complaining of having the worst headache of her life and stiffness of her neck. What does she have? What would lumbar puncture show?
She has subarachnoid hemorrhage. LP shows xanthochromia (yellow hue due to bilirubin breakdown).
What are berry aneurysms? Where are they located ? What are they associated with?
Berry aneurysms are thin walled saccular outpouchings that lack a media layer, increasing the risk for rupture
Most frequently located in the anterior circle of Willis at branch points of the anterior communicating artery
Associated with Marfan syndrome and autosomal dominant polycystic kidney disease.
What are the cause of subarrachnoid hemorrhage?
85% due to rupture of berry aneurysm, other causes include AV malformations and an anticoagulated state.
What are the subtypes of ischemic stroke?
Thrombotic, embolic, LACUNAR
