Stroke Flashcards
Cerebral thrombus
Ischemic stroke
Blockage that originates in cerebral vessel and causes obstruction; atherosclerotic
Large vessel- MCA, ICA
Small vessel- lacunar strokes d/t blockage of lenticulostriate arteries, medullary arteries
Cerebral embolus
Ischemic stroke
Clot that travels to the brain from another area
Heart– a-fib, valvular disease
ICA– originates at bifurcation of common carotid artery
Cerebral perfusion pressure
Low pressure results in ischemic stroke
40-50mmHg
Cardiac arrest, shock
Possible watershed stroke- blood fails to reach arteries on the outer areas of the brain
ABCD2 Prediction Rule
Age >60 (1)
BP =/>140/90. (1)
Clinical presentation:
-unilateral weakness, with or without speech (2)
-Speech impairment without unilateral weakness
Duration: >/= 60 mins (1)
Diabetes (1)
Intracerebral Hemorrhage
Rupture of blood vessels within the brain
Common locations: basal ganglia, cerebellum, brainstem, cortex
Causes/risk factors: HTN, drug use, anticoagulant use
Subarachnoid hemorrhage
Rupture of vessels in the subarachnoid space, btw the brain and the skull
Sx’s: sudden onset of “thunder clap HA’, neck pain, n/v
Common cause: cerebral aneurysm
Most deadly
Saccular aneurysm
Rounded/irregular swellings in arteries that are less resistant to changes in pressure
Common locations: vessel bifurcation- sheer forces
ACA; ICA/PCA
Aneurysm w/ diameter of =/>10mm are at critical risk of rupture.
Arteriorvenous malformation
Congenital defect- abnormal tangle of blood vessels
Middle Cerebral Artery
Most common stroke location
Supplies: primary motor/sensory cortices, Broca’s/Wernicke’s Aphasia
-Contralateral face/arm>LE weakness
-Contralateral loss of sensation UE and face>LE
-Contralateral homonymous hemianopsia
-Non-dominant- neglect and impairment of nonverbal communication
-
Lacunar Stroke
Caused by chronic HTN
Lenticulostriate arteries
Supplies: basal ganglia and internal capsule
Contralateral weakness
Posterior Cerebral Artery
Supplies: occipital lobe, inferior part of temporal lobe, deep structures diencephalon- thalamus
-Contralateral weakness
-Contralateral Homonymous hemianopsia
-Contralat eye paresis
-Calcerine sulcus- blindness of contralat visual field
-Thalamic syndrome- severe pain, contrast loss of sensation, flaccid hemiparesis
-Hippocampus- impairs declarative memory
Anterior Cerebral Artery
RARE d/t collateral circulation of ant communicating artery
Supplies: primary motor and sensory cortices (mainly lower limb), supplementary motor area, prefrontal cortex
-Contralateral weakness LE>UE/face, causing incontinence
-Frontal lobe behavioral abnormalities- poor judgment, decreased attention/motivation, difficulty regulating emotions, apraxia
Watershed Stroke
Results from hypo perfusion- heart disease, cardiac arrest, shock
Proximal arm/leg weakness w/ preservation of distal strength (main in a barrel)
Posterior Inferior Cerebellar Artery
Lateral Medullary Syndrome aka
Wallenberg Syndrome
Supplies: cerebellum, medulla
-Ipsi ataxia
-Contralat weakness
-Contralat loss of pain/temperature in body, ipsi face
-Dizziness/vertigo
-Diploplia
-Dysphagia
-Dysarthria
-Ipsi Horner’s syndrome- ptosis, pupil constriction, decreased sweating
Anterior Inferior Cerebellar Artery
Lateral pontine syndrome
Supplies: cerebellum, CN VII and VIII
-Ipsilat ataxia
-Contralat weakness
-Contralat sensory impairment (pain and temp)
-Dizziness/vertigo
Patterns of Sensory Loss
Dissociated
CN signs opposite long tract signs –> brainstem disorder
Loss of pain and temperature, vibration, touch, position on different sides of body –> SCI
Patterns of Sensory Loss
Global
Impairments of all sensory modalities on one side of body, plus UMN signs–> cortical injury
Impairments of all sensory modalties on one side of body, plus LMN signs– peripheral nerve injury
Supratentorial
Damage to cerebral cortex or diencephalon
Results in cognitive, judgment, affect, and/or language deficits
Infratentorial
Damage to brainstem or cerebellum
Results in abnormal vital signs, automatic movement, adjustments, posture/gait, and/or breathing patterns
Anosognosia
Denial of symptoms
Often present in patients with neglect
Associated with damage to the R posterior ínsula
Somatotopagnosia
Lack of awareness of body structure and relationship of body parts in self and others
Most common with damage to L parietal area and temporal lobe
Finger agnosia
Inability to name, touch, identify specific fingers on self or others
Apraxia
Inability to perform purposeful movement despite adequate strength, coordination and sensation.
Ideomotor apraxia
Difficulty planning and completing tasks on command
Ideational apraxia
Inability to conceptualize or perform tasks on command or automatically.
Gerstmann Syndrome
Symptoms related to damage to parietal lobe near angular gyrus
-R/L discrimination disorder
-Finger agnosia
-Agraphia
-Acalculia
