Flashcards in Stroke I Deck (23):
What is the definition of a stroke?
fixed neuro deficit of sudden onset, usually due to pathology in blood vessels.
What is a thrombotic stroke?
stroke caused by thrombosis of large intracranial vessels, usually at points of bifurcation.
What is typical onset of thrombotic stroke?
stuttering onset, often while the pt is asleep
Characteristics of middle cerebral artery thrombotic stroke?
arm and leg of contralateral side equally effected if infarct involves the internal capsule. visual field cut and higher cortical deficits like aphasia, apraxia, agnosia are also seen
characteristics of vertebro-basilar stroke
brain stem findins: opthalmoplegia, pupillary abnormalities, facial weakness and numbness, difficulty with speech and swallowing, long tract signs, vertigo, ataxia, syncope
What is lateral medullary syndrome?
infarction of the vertebbral artery. nausea, vomiting, cardiac arrhythmias, ipsilateral facial numbness and and contralateral body numbness, ipsilateral ataxia, hoarseness, dysphagia, ipsilateral Horner's syndrome (sympathetic defects)
What is an embolic stroke?
stroke due to the occlusion of small, distal cortical vessels from an embolus.
What is the onset of an embolic stroke?
usually of abrupt onset and occur during the day. deficit maximal at the start with gradual resolution
What are the sources of emboli for embolic strokes?
atherosclerotic plaques of ascending aorta, internal carotids, and vertebro-basilar system
cardiac sources: usually in the setting of recent myocardial infarction with mural thrombosis, afib, low output state, or valvular heart disease, or paradoxical emboli from right heard due to ASD or patent foramen ovale
What is a hemorrhagic stroke?
stroke due to cerebral hemorrhage of sudden onset
What are the 4 types of hemorrhagic stroke?
hypertensive intracerebral hemorrhage
arterio venous malformation
What is hypertensive intracerebral hemorrhage? What are the most common sites?
rupture of small, penetrating blood vessels from chronic hypertension.
pons, cerebellum, thalamus, and putamen
What is amyloid angiopathy?
cause of lobar hemorrhage in elderly patients, esp. those with a history of hypertension. amyloid protein is deposited in the walls of thecerebral blood vessels and weakens them --> more prone to spontaneous hemorrhage. this proteins is the same as the amyloid in brains of Alzheimer's patients
What is a lacunar stroke?
due to infarction of small, deep, penetrating blood vessels, usually in setting of chronic hypertension or DM
4 clinical lacunar stroke syndromes
pure motor: internal capsule or pons stroke
pure sensory: thalamus
clumsy hand-dysarthria: internal capsule/pons
leg paresis-ataxia: internal capsule/pons
What happens with surrounding edema in stroke pts? (when is it seen, what type of stroke, what are symptoms)
prominent 72-96 hrs poste event; usually in large, thrombotic occlusions. patient is usually lethargic
What is cerebral herniation?
seen with massive thrombotic occlusion with resultant cerebral edema: cerebellar infarcts with edema may compress the pons and kill patient
What is stroke in evolution?
due to progressive occlusion of a large vessel from ongoing atherosclerosis. worsening neuro deficits in the SAME vascular distribution
What is locked-in syndrome?
stroke syndrome of preserved consiousness and sensation with absent motor output (maybe eye blinking and vertical eye movements ok) due to infarction of branches of the basilar artery supplying the ventral portions of the brain stem
What happens with seizure and strokes? WhAt is the time course?
early complication of embolic strokes, since they often lodge in the periphery
late (9 mo. or more) complication of thrombotic strokes,esp. seen in eldery with metabolic derangements
What is hemorrhagic transformation?
usually of embolic strokes and sometimes of large throbitic infarcts within 24 hrs of stroke onset. aanticoagulation and severe hypertension may incr. incidence. may also occur with tumors
What presents as stuttering onset?