Vascular Disease Flashcards
The anterior circulation comes from what main arteries?
the common carotids
What areas are supplied by the ACA?
anterior medial cerebral hemispheres, caudate nuclei and basal frontal lobes
What artery connects the two ACAs?
the anterior communicating artery
True or false: the lenticulostriate arteries branches to the basal ganglia and internal capsule off the ACA.
false - they come off the MCA
What areas are supplied by the MCA?
the basal ganglia/internal capsule
lateral cerebral hemispheres superior to the sylvian fissure
temporal and inferior parietal lobes
What artery arises from the ICA after the ophthalmic and posterior communicating artery to course along the optic tract giving off branches to the globus pallidus and posterior limb of the internal capsule and then supplies the medial temporal lobe and the lateral genicular body?
the anterior choroidal artery
In general terms, the posterior circulation comes from what vessels?
the vertebral arteries off the subclavian
The intracranial vertebral arteries join to form what artery?
the basilar at the pontomedullary junction
What percentage of strokes are ischemic?
80%
What are the three general categories of ischemic stroke/
thrombosis
embolism
systemic hypoperfusion
What are some causes of occlusive vascular pathologies affecting the brain?
atherosclerosis is the most common
vasoconstriction
fibromuscular dysplasia
arterial dissection
WHere do emboli causing embolic strokes typically arise from?
heart, aorta, neck arteries or intracranial arteries
In general, what will happen in a left cerebral hemisphere stroke?
right hemiparesis
right hemisensory loss
aphasia
in large lesions, conjugate deviation of the eye to the left, right hemianopia or hemi-inattention
In general, what will happen in a right cerebral hemisphere stroke?
left hemiparesis left hemisensory loss poor drawing and copying neglect of the left visual field large lesions with conjugate deviation of the eyes to the right
Occlusion of what vessel will give you lateral medullary syndrome (or wallenberg syndrome?
intracranial vertebral artery occlusion
What are the signs and symptoms of lateral medullary syndrome?
ipsilateral facial pain or reduced pain and temp sensation on the ipsilateral face, or both
loss of pain and temp in the contralateral limbs and body
ipsilateral horner’s syndrome
nystagmus
incoordination of the ipsilateral arm
leaning and veering while sitting or walking with gait ataxia
in deep lesions: dysphagia and horseness
What signs and symptoms will you see in a bilateral pontine base stroke due to basilar artery occlusion or pontine hemorrhage?
quadriparesis
unilateral or bilateral conjugate gaze paresis, sometimes internuclear ophthalmoplegia and VIth nerve palsy
if the medial tementum is involved bilaterally, coma
What will you see in a cerebellar infarction?
gait ataxia, often inability to walk
dysarthria
ipsilateral arm dysmetria
What symptoms would you see in a left PCA territory stroke?
right homonymou shemianopia
at times, amnesia
alexia without agraphia when the splenium of the corpus callosum is involved
What symptoms would you see in a right PCA territory stroke?
left homonymous hemianopia
at times, left-sided visual neglect
What are the four main lacunar stroke syndromes?
pure motor
pure sensory
dysarthria-clumsy hand syndrome
ataxic hemiparesis
Where is the lesion in a pure motor stroke and what symptoms do you expect?
the posterior limb of the internal capsule with contralateral weakness of the arm, face and leg without sensory, visual or cognitive or behavioral signs
Where is the lesion in a pure sensory stroke and what symptoms do you expect?
Thalamus
paresthesiae of the contralateral body, limbs and face without any other deficit
WHere is the lesion in dysarthria-clumsy hand syndrome?
pons, with slurred speech and clumsiness of the contralateral hand
Where is the lesion in ataxic hemiparesis?
pons with weakness and ataxia of the contralateral limbs, often greater in the leg and foot than in the arm and hand
Patient presents with severe retro-orbital headache and horner syndrome (with preserved perspiration). What happened?
carotid dissection ipsilateral to where the pain is
Why do you get a horner syndrome with preserved perspiration with a carotid dissection?
you get horner’s syndrome due to involvement of the ascending oculosympathetic tract but perspiration is preserved because sudomotor fibers ascend with the external carotid, not the internal carotid
Patient presents with neck pain and a third nerve palsy after going to the chiropractor. What happened?
vertebral artery dissection
What color will a hemorrhage be on CT? What color will infarction be on CT?
hemorrhage is white
infarction is dark
Which imaging test is more sensitive than CT to identify acute infarction?
MRI with diffusion-weighted imaging
What are the three general strategies for reperfusion?
intravenous thrombolysis with tPA
intra-arterial thrombolysis near the clot
mechanical clot retrieval
What is the time limit for tPA administration?
4.5 hours
What is the time limit for intra-arterial thrombolysis or mechanical clot retrieval?
6 hours
Prevention of further ischemia is usually necessary 24 hours after tPA administration. What should you use if the stroke was caused by lacunar infarction or atherosclerotic disease?
high-dose aspirin
or if they had been on aspirin prior to the stroke (failed aspirin), clopidogrel
What should you use to prevent further ischemia if the stroke was caused by atrial fibrillation with embolization?
heparin with eventual transition to warfarin
Subarachnoid hemorrhage is usually bleeding from where?
an aneurysm in the circle of willis
Describe management for SAH?
aneurysms can be surgically clipped or soiled
Nimodipine to minimize vasospasm and delayed brain ischemia
What is the most common cause of intracerebral hemorrhage? WHat about in the elderly?
hypertension in general
in the elderly, consider cerebral amyloid angiopathy affecting the parietal and occipital lobes
WHat are the most common locations for hypertensive intracerebral hemorrhage?
basal ganglia-internal capsule, caudate, thalamus, pons, cerebellum
What are three congenital malformations that can lead to brain bleeds?
arteriovenous malformations
developmental venous anomalies
cavernous angiomas
