Strokes Flashcards
What are the most vulnerable areas of the brain to ischemic stroke
Hippocampus (MOST)
Neocortex (layers 3, 5, 6)
Cerebellum (purkinje cells)
Watershed areas
When will an ischmic change be detected on MRI and CT
CT: in 6-24 hours (will exclude hemmorage though)
MRI: within 3-30 minutes
What is seen Histologically post stroke?
12-24 hours
Eosinophilic cytoplasm + pyknotic nuclei (red neurons)
What is seen Histologically post stroke?
24-72 hours
Necrosis + neutrophils
What is seen Histologically post stroke?
3-5 days
Macrophages (microglia)
What is seen Histologically post stroke?
1-2 weeks
Reactive gliosis (astrocytes) + vascular proliferation
What is seen Histologically post stroke?
>2 weeks
Glial scar
What are the 3 types of ischemic stroke and how do they tend to differ
Thrombotic: clot formation directly at site of infaction (usually atherosclerotic) (commonly MCA)
Embolic: embolus from another part of body; can affect MULT vascular territories (afib, DVT w/ patent foramen, carotid stenosis)
Hypoxic: due to hypoperfusion or hypoxia; common during cv surgeries tends to affect watershed areas
Presentation of altered level of consciousness, bulging fontanelle, hypotension, seizures, and coma in a preme infant
intraventricular hemorrhage into ventricles/perivent white matter; commonly due to rupture in germinal matrix due to reduced glial fiber support and impaired BP autoreg in premature infants
What intracranial hemorrhage does not cross suture lines
Epidural hematoma (mm artery damage)
What intracranial hemorrhage does cross suture lines
Subdural hematoma (bridging veins tear)
What is one possible associated risk with an Epidural Hematoma
Transtentorial herniation –> CN III palssy
What causes a hypodense vs a hyperdense subdural hematoma
Hyperdense: acute (trauma or high impact)
HypOdense: chronic (mild trauma, cerebral atrophy, elderly, alcoholism)
Which type of brain bleed would you see in a shaken baby
Subdural hematoma (also may see broken ribs)
If a spinal tap is bloody or xanthochromic what would the associated hemorrhage be
Subarachnoid hemorrhage ( can be due to trauma, rupture of aneurysm or arteriovenous malformation (worst headache of my life, rapid time course)
What is the relationship of vasospasm to stroke pathology
After a stroke (usually subarachnoid) 3-10 days after due to blood breakdown or rebleed –> vasospasm occurs
This leads to an ischemic infarct
(pts given nimodipine to prevent/reduce)
A subarachnoid hemorrhage puts you at greater risk for what in the future
developing communicating and/or obstructive hydrocephalus
What are the most common causes of intraparenchymal hemorrhage?
Systemic hypertension (most common) Amyloid angiopathy (recurrent lobar hemorrhagic stroke in elderly) Vasculitis Neoplasm Secondary to reperfusion from ischemic
Where are hypertensive hemorrhages most commonly seen?
(charcot bouchard microaneurysms- not visible on CT) Basal ganglia (lenticulostriate) (MC) Thalamus Pons Cerebellum
A stroke in this artery covers what areas:
Middle Cerebral Artery (3)
Motor/Sensory Cortices (upper limb/face) Temporal lobe (wernicke area) Frontal lobe (brocas area)
A stroke in this artery presents with what symptoms:
Middle Cerebral Artery
Contralateral paralysis and sensory loss (face and upper limb)
Aphasia if in dominant hemisphere
Hemineglect if on nondominant
Wernicke aphasia is associated with a right superior quadrant visual field defect due to temporal lobe involvement
A stroke in this artery covers what areas:
Anterior Cerebral Artery (1)
Motor/Sensory Cortices (lower limb)
A stroke in this artery presents with what symptoms:
Anterior Cerebral Artery
Contralateral paralysis and sensory loss lower limb- URINARY INCONTINENCE
A stroke in this artery covers what areas: Lenticulostriate Artery (2)
Striatum
Internal Capsule
A stroke in this artery presents with what symptoms:
Lenticulostriate Artery
Contralateral paralysis ABSENCE OF CORTICAL SIGN (common location of lacunar infarcts due to hyaline arteriosclerosis due to hypertension)
A stroke in this artery covers what areas:
Anterior Spinal Artery (3)
Lateral Corticospinal Tract
Medial lemniscus
Caudal medulla-hypoglossal nerve
A stroke in this artery presents with what symptoms:
Anterior Spinal Artery
Contralateral paralysis (upper and lower limb) (lateral corticospinal)
Dec Contralateral proprioception (med lem)
Ipsilateral hypoglossal dysfunction (tongue deviates ipsilaterally (lick your lesion)
A stroke in this artery covers what areas:
Posterior Inferior Cerebellar Artery (6)
Lateral Medulla: Nucleus ambiguus (CN IX, X, XI) Vestibular nuclei Lateral spinothalamic tract Spinal Trigem nucleus Sympathetic fibers Inferior Cerebellar peduncle
A stroke in this artery presents with what symptoms:
Posterior Inferior Cerebellar Artery
Dysphagia, hoarseness, dec gag reflex, hiccups (nuc ambiguus)
Vomiting, vertigo, nystagmus
Dec pain/temp from CONTRA body IPSI face (spino thal, spinal trigem nuc)
Ipsilateral horner (symp fibers)
Ipsilateral ataxia, dysmetria (inf ped)
A stroke in this artery covers what areas:
Anterior Inferior Cerebellar Artery (8)
Lateral Pons: Facial Nucleus Vestibular Nuclei Spinothalamic tract Spinal trigeminal nucleus Sympathetic fibers Middle Cerebellar peduncles Inferior Cerebellar peduncles Labyrinthine Artery
A stroke in this artery presents with what symptoms:
Anterior Inferior Cerebellar Artery
Paralysis of face (LMN vs UMN in cortical stroke) (dec lac, sal, taste from ant 2/3 tongue) (CNVII)
Vomiting Vertigo Nystagmus (VN)
Dec pain/tem from CONTRA body IPSI Face (spinothal, spinal trigem nuc)
Ipsilateral horners (symp fibers)
Ataxia, dymetria (mid/inf ped)
Ipsilateral sensorineural defness/vertigo (lab)
A stroke in this artery covers what areas: Basilar Artery (5)
Pons, Medulla, Lower midbrain Corticospinal tract Corticobulbar tract Ocular cranial nerve nuclei Paramedian pontine reticular formation
A stroke in this artery presents with what symptoms:
Basilar Artery
RAS spared- So preserved consciousness
Quadriplegia (CS/CB)
loss of voluntary face, mouth, tongue movements (CS/CB)
Loss of horizontal but not vertical eye movements (Ocular/PPRF)
A stroke in this artery covers what areas:
Posterior Cerebral Artery (1)
Occipital lobe
A stroke in this artery presents with what symptoms:
Posterior Cerebral Artery
Contralateral hemianopia with macular sparing
alexia without agraphia (dominant hemisphere/ PT CAN WRITE BUT NOT READ)
What would be seen with a:
Cingulate (subfalcine) herniation under falx cerebri
Can compress anterior cerebral artery
What would be seen with a:
Transtentorial (central downward herniation)
caudal displacement of brain stem
can rpture paramedian basilar artery branches –> duret hemorrhages
What would be seen with a:
uncal herniation
Uncus=medial temporal lobe
Compresses ipsilateral CNIII and contralateral crus cerrebri against kernohan notch
see CNIII palsy and or ipsilateral hemiparesis (false localizing sign)
What would be seen with a:
Cerebellar tonsillar herniation into foramen magnum
Coma and death when they compress the brainstem
