Vascular Flashcards
What is the major cause of morbidity and mortality in SAH?
Vasospasm and ischemia
What is the best for imaging test for suspected SAH?
CT without contrast
If no evidence of bleeding is seen on CT in the setting of suspected SAH, what is the next step?
Lumbar puncture to look for RBCs
Where are the most common sites in the cerebral vasculature for saccular (berry) aneurysms?
Anterior communicating artery aneurysms are the most common location (30%).
Posterior communicating artery aneurysms make up 25%.
Middle cerebral artery aneurysms account for 20% of saccular (berry) aneurysms.
What two mechanisms cause pain in the setting of a saccular (berry) aneurysm?
Rapid enlargement and bleeding
What labs should be drawn in the setting of stroke when considering thrombolytic therapy?
CBC, PR/PTT, cardiac enzymes, troponin, and BUN/creatinine
What are the 4 deadly Ds of posterior circulation strokes?
Diplopia, Dizziness, Dysphagia, Dysarthria
What are the major findings of a middle cerebral artery stroke?
MCA stroke can cause CHANGes -
- Contralateral paresis and sensory loss in the face and arm
- Hemiparesis
- Aphasia (dominant)
- Neglect (nondominant)
- Gaze preference toward the side of the lesion
How is ischemic stroke managed?
tPA if it has been < 3hrs and there is no bleeding or absolute contraindications. Note that BP should be <185/110 to give tPA.
Give ASA if it has been > 3 hrs (or switch to clopidegrel in pts already taking ASA).
How is increased ICP in the setting of ischemic stroke managed?
Mannitol and hyperventilation
What is the single greatest risk factor for stroke?
Hypertension
What are the manifestations of an ACA stroke?
Contralateral paresis and sensory loss in the leg, cognitive or personality changes
What are the manifestations of a PCA stroke?
Vertigo, homonymous hemianopsia
What are the manifestations of a lacunar stroke?
Symptoms are pure motor, pure sensory, ataxic hemiparesis, or dysarthria
When should carotid endarterectomy be considered?
If stenosis is > 60% with symptoms or > 70% without symptoms. Note that it is contraindicated in 100% occlusion
What is the most common cause of intracerebral hemorrhage?
Hypertension
Is neurosurgical intervention required for either epidural or subdural hematomas?
It is for epidural because it can quickly cause herniation. Subdural only require if they are symptomatic - some may regress spontaneously
What does sudden onset of cerebellar ataxia with associated vomiting and depressed level of consciousness suggest?
Cerebellar stroke
What visual field anomaly may accompany Werinke’s aphasia?
Contralateral homonymous superior quandrantanopia (due to infarct of the inferior division of the MCA)
Strokes of what artery most commonly lead to transcortical sensory aphasias (impaired comprehension with retained fluency and repetition)?
Left posterior cerebral artery - lesion to the inferior portion of the temporal lobe
At what level of the brainstem do the vertebral arteries join to form the basilar artery?
At the pontomedullary junction
How do large left cerebral hemisphere strokes affect vision?
Can cause conjugate deviation of the eyes to the left; as well as right hemianopia or hemi-inattention
How do large right cerebral hemiphere strokes affect vision?
Conjugate gaze to the right, left hemianopia, neglect of the left visual field
Stroke of what cerebral hemisphere leads to problems with drawing and copying?
Right
What are symptoms of a lateral medullary stroke (Wallenberg syndrome) caused by vertebral artery occlusion?
- Ipsilateral face pain, or decreased pain and temp sensation on the ipsilateral face, or both
- Loss of pain and temp in the contralateral limbs and body
- Ipsilateral Horner syndrome
- Nystagmus
- Incoordination of the ipsilateral arm
- Leaning and veering while sitting or walking with gait ataxia, vertigo
- In deep lesions, dysphagia and hoarseness
What symptoms does a left PCA stroke cause?
- Right homonymous hemianopia
- At times, amnesia
- Alexia without agraphia when the splenium of the corpus callosum is involved
What symptoms does a right PCA stroke cause?
- Left homonymous hemianopia
2. At times, left-sided visual neglect
What are the types of lacunar strokes (stroke of a penetrating artery off the MCA)?
Pure motor stroke, pure sensory stroke, dysarthria-clumsy hand syndrome, and ataxic hemiparesis
How does dissection of the internal carotid artery present?
Severe retro-orbital headache ipsilateral to the lesion. Patients may also have an ipsilateral Horner syndrome (although perspiration remains intact because those fibers travel with the external carotid)
Where are the most common sites for intracerebral hemorrhage (bleeding into the brain parenchyma, usually due to hypertension)?
Basal ganglia/internal capsule, caudate nucleus, thalamus, pons and cerebellum
What is the best treatment for an acute vertebral artery dissection?
IV heparin followed by warfarin in 3-6 months
What are the most common sites of intracerebral hemorrhage caused by HTN?
The basal ganglia, thalamus, pons, and cerebellum, in order of decreasing frequency
What is the most common cause of subarachnoid hemorrhage?
Aneurysmal rupture
What initial test should be done when a patient presents with a stroke?
CT scan without contrast to distinguish whether it is a hemorrhagic or ischemic stroke. If it is ischemic, then the patient can receive tPA if in the 3 hour window and no contraindications
What is amyloid agiography?
The most common cause of lobar hemorrhage in elderly patients without hypertension - due to the deposition of beta-amyloid protein in blood vessels
What are Charcot-Bouchard aneurysms?
Very small aneurysms due to chronic hypertension - usually affects lenticulostriate arteries
What is the most common cause of subarachnoid hemorrhage in persons < 40 years and > 40 years of age?
< 40: AVM
>40: Aneurysm
An aneurysm of what artery is most likely to compress the occulomotor nerve?
The posterior communicating artery
What is the presumed mechanism of transient monocular blindness?
Embolism to the central retinal artery
What does tonic gaze deviation usually indicate?
Damage (e.g. stroke) to the frontal eye field on the side the eyes are deviated towards (the frontal eye fields direct gaze to the contralateral side)
What type of intracranial bleeding may be a complication of ventriculoperitoneal shunting?
Subdural hematoma because the reduction in ICP can cause the brain to pull away from the covering meninges, stretching and potentially rupturing the bridging veins
What is ischemic optic neuropathy?
Causes a sudden painless loss of vision in one eye - the visual field defect is typically an inferior altitudinal defect with involvement of the central loss of vision. Due to an occlusion of the posterior ciliary artery (branch of the ophthalmic artery)
What vessel is likely occluded in a patient with vertigo?
PICA
