Term
| what are the 4 major signs of acute neuron injury, when does it show up |
|
Definition
12h
eosinophilic cytoplasm
spheroids
break down of BBB
cerebral edema |
|
|
Term
| what is a spheroid made of, how does it effect the cell |
|
Definition
| eosinophil ball causes axon swelling and loss of transport |
|
|
Term
| what are the physical changes in a cell due to spheroids 2 |
|
Definition
cell body shrinks, pyknosis of nucleus, disspipearance of nucleolus, loss of nissil substance
OR
cell body enlarges, nucleus displacement, nucleolus enlargement, dispersion of nissil substance (central chromatolysis) |
|
|
Term
| what are signs of brain aging |
|
Definition
| lipofuscion accumulation in cytoplasm and lysosomes |
|
|
Term
| what are 2 signs of neurodegeneration |
|
Definition
intraceuular inclusions: lewy bodies, tangles
dystrophic neuritis: thick neuronal processes |
|
|
Term
| what are signs of brain viral infections |
|
Definition
| inclusions with virus in them (CMV, HSV, rabies) |
|
|
Term
| define cerebral edema, 3 major brain changes, 2 types |
|
Definition
accumulation of fluid in brain PARENCHYMA
softens brain, flattens gyri, compresses ventricles
vasogenic and cytotoxic |
|
|
Term
| vasogenic cerebral edema: define, causes 2 |
|
Definition
BBB is disrupted, fluid moves from vessels into intracellular space
inflammation increases permeability, tumors |
|
|
Term
| cytotoxic cerebral edema: define, causes 3 |
|
Definition
increase in intracellular fluid due to neuron or glial membrane injury
hypoxia, ischemia, toxins |
|
|
Term
| what is the normal pathway of CSF |
|
Definition
choroid plexus in 3rd ventricle makes
goes through openings in 4th ventricle to arachnoid space
goes through arachnoid granulations
into the circulation |
|
|
Term
|
Definition
| accumulation of CSF in VENTRICLES |
|
|
Term
| 3 causes of hydrocephalus |
|
Definition
impaired flow: scaring of meninges
impaired reabsorption: arachnoid granules clogged by blood or scared
excess production (rare): papilloma of choroid plexus |
|
|
Term
| what are the effects on the brain of hydrocephalus in general in an adult and kid |
|
Definition
before sutures close: enlarges head
after sutures close: expansion of ventricles, stretching of brain, increased ICP |
|
|
Term
|
Definition
non-communicating
communicating (normal pressure)
Ex vacuno |
|
|
Term
| non-communicating hydrocephalus: define, 3 causes |
|
Definition
obstruction in ventricles causes enlargement proximal to block
obstructed foramen on Monro
compression of cerebral aqueduct (of sylvius)
cyst blockning intraventricular foramen |
|
|
Term
| communicating hydrocephalus: define, 1 cause |
|
Definition
reduced reabsorption causes all ventricles to enlarge stretching corona radiata
scaring or fibrosis of arachnoid granulations |
|
|
Term
| communicating hydrocephalus: 3 signs, why |
|
Definition
compression of corona radiata
wacky: dementia
wet: urinary incontinence
wobbly: gait instability |
|
|
Term
| ex vacuno hydrocephalus: define |
|
Definition
| decreased brain parenchyma makes ventricles look big (not really hydrocephalus) |
|
|
Term
| brain herniation: 3 causes, process of damage |
|
Definition
ICP increase, abscess, or tumor causes expansion of brain onto immobile dural folds and bone
pinching causes vascular compression, infarction, and swelling |
|
|
Term
| what are the 3 types of brain herniations |
|
Definition
subfalcine (cingulate)
transtentorial (uncinate)
tonsilar (cerebellar) |
|
|
Term
| subfalcine (cingulate) brain herniation: cause, effect |
|
Definition
brain is pushed to side and cingulate gyrus is pushed under FALX CEREBRI
compresses ANTERIOR CEREBRAL ARTERY BRANCHES TO HEMISPHERES causing infarction |
|
|
Term
| transtentorial (uncinate) brain herniation: cause |
|
Definition
| brain is pushed down onto TENTORIUM CEREBELLI and UNCUS of temporal lobe is stuffed through TENTORIAL NOTCH between brainstem and tentorium cerebelli |
|
|
Term
| 4 anatomical effects of transtentorial (uncinate) herniation |
|
Definition
compression of CNIII
compression of posterior cerebral artery
tearing of penetrating vessels to midbrain and pons
contralateral cerebral peduncle compression |
|
|
Term
| what is the result of a transtentorial (uncinate) herniation compressing CN III 2 and why |
|
Definition
damage to LATERAL RECTUS and SUPERIOR OBLIQUE causes eye to move DOWN AND OUT
DILATION of pupil due to compormised parasympathetics |
|
|
Term
| what is the result of a transtentorial (uncinate) herniation compressing posterior cerebral arery |
|
Definition
| causes infarct damage to the VISUAL CORTEX |
|
|
Term
| what is the result of a transtentorial (uncinate) herniation tearing penetrating vessels to midbrain and pons |
|
Definition
| DURET HEMORRHAGES on MIDLINE paramedial midbrain and pons |
|
|
Term
| what is the result of a transtentorial (uncinate) herniation compressing contralateral cerebral peduncle |
|
Definition
| hemiparesis IPSILATERAL to tentorial herniation |
|
|
Term
| tonsilar herniation: cause, effect |
|
Definition
cerebellar tonsil pushed through foramen magnum compresses brainstem
CARDIOPULMONARY ARREST |
|
|
Term
| what are the two types of cerebrovascular disease |
|
Definition
|
|
Term
| what are the two types if ischemia |
|
Definition
|
|
Term
| what are the two types of focal ischemia |
|
Definition
|
|
Term
| what are the 4 causes of focal ischemia, which is most common |
|
Definition
embolism - most common
thrombus
lacunar stroke
hypertensive cerebrovascular disease |
|
|
Term
| what are the 4 causes of global ischemia |
|
Definition
hypoglycemia
anemia
hypotension (<50mmHg)/shock
athlerosclerosis of large vessels feeding brain |
|
|
Term
| what are the two types of hemorrhage |
|
Definition
|
|
Term
| what are the two types of subarachnoid hemorrhage, which is most common |
|
Definition
saccular/berry aneurysm - most common
non-saccular aneurysm |
|
|
Term
| what are the 2 types of intracranial hemorrhage |
|
Definition
primary parenchymal brain hemorrhage
cerebral amyloid angiopathy |
|
|
Term
| why do focal ischemias often go unnoticed |
|
Definition
| circle of willis probides collateral circulation to many regions |
|
|
Term
| what are 8 causes of emboli to the brain, brief explination of each |
|
Definition
cardiac mural thrombi: thrombus forms on stasis in heart then is thrown
AFib: chruning of blood causes clot then is thrown
athlerosclerosis: rupture allows clot to form on damaged tissue and is broken off
paraxodian embli: undiagnosed septi in heart allows emboli to move from venoous side and into circulation instead of lungs
thromboemboli: DVT
fat: release from fractured bone
tumor: breaks off into circulation
air: injections, diving |
|
|
Term
| what are the 3 most common locations a cerebral emboli might land, why |
|
Definition
middle cerebral artery: big, straight path
branch points
existing luminal stenosis |
|
|
Term
| how does the tissue look when an emboli causes infarct, why |
|
Definition
| cuts blood off long enough for neurons to die then is lysed and blood moves back into area causing hemorrhagic infarcts at PERIPHERY OF CORTEX (HEMORRHAGIC/RED INFARCTS) |
|
|
Term
| how is a cerebral emboli tx |
|
Definition
| TCA cannot be used, it is already hemorrhaged, this is why it has time limit |
|
|
Term
| what is the cause of a thrombus in the brain |
|
Definition
| athlerosclerosis ruptures exposing collagen on tissue allowing clot to form, it is lysed then quickly regrows |
|
|
Term
| what are the 3 most common locations for brain thrombus |
|
Definition
carotid bifurcation
origin of MCA
basilar artery |
|
|
Term
| how does the tissue look when a thrombus causes brain infarct, why |
|
Definition
| pale PERIPHERIAL CORTEX due to vessel blockage (it cannot be lysed and cleared like a emboli, it will just grow back) (WHITE/NON-HEMORRHAGIC INFARCT) |
|
|
Term
| what is the treatment for cerebral thrombus |
|
Definition
|
|
Term
| what is the cause of a lacunar stroke, how does it damage, signs in pt |
|
Definition
hayline arteriolosclerosis in small vessels of the brain due to HTN/DM thickening walls and decreasing blood in LENTICULOSTRIATE vessels in deep brain
NO SIGNIFICANT NEUROLOGICAL IMPAIRMENT |
|
|
Term
| 4 most common places for lacunar stroke |
|
Definition
basal ganglia
thalamus
internal capsule
pons |
|
|
Term
| 6 effects HTN has on the cerebral vasculature |
|
Definition
hayline artery sclerosis: weakens vessels
CHARCOT-BOUCHARD MICROANEURYSMS: <300um, rupture and bleed
LACUNAR STROKES
SLIT HEMORRHAGES: rupture of penetrating vessels followed by reabsorption of blood leaves a cavity
HYPERTENSIVE ENCEPHALOPATHY: BP>130 increases iCP caused edema, petechiae, necrosis in arteries
global cerebral dysfunction: headache, confusion, vomiting, convulsion, coma |
|
|
Term
| define global cerebral infarct |
|
Definition
| WIDESPREAD hypoxic injury due to DECREASED PERFUSION |
|
|
Term
| what are the three severities of global cerebral infarcts, what is a major characteristic of each |
|
Definition
mild: confusion
moderate: watershed infarcts
severe: diffuse necrosis, death |
|
|
Term
| watershed infarct: define, location, cause |
|
Definition
wedge shaped infarct at edge of perfusion area that does not recieve blood
anterior/posterior cerebral
posterior/medial cerebral
hypotension |
|
|
Term
| what are the areas of the brain with least collateral circulation and shows signs of infarct first 6, and symptoms for some 3 |
|
Definition
pyrmidal cells of CA1 hyppocampus in temporal lobe: long term memory
purkinje cells in cerebellum: ataxia
pyrmidal cells of neocortex: cortical laminal necrosis (death of certin layers)
thalamus
basal ganglia
deep white matter |
|
|
Term
| ischemic effect on neurons 0-6h: appearance, activities |
|
Definition
|
|
Term
| ischemic effect on neurons 6-12h: appearance, activities |
|
Definition
no activity
pale, soft swollen, indistinct gray/white junctions |
|
|
Term
| ischemic effect on neurons 12-24h: appearance, activities |
|
Definition
RED NEURONS (LIQUIFACTIVE NECROSIS)
pale, soft swollen, indistinct gray/white junctions |
|
|
Term
| ischemic effect on neurons 24-48h: appearance, activities |
|
Definition
NEUTROPHILS
pale, soft swollen, indistinct gray/white junctions |
|
|
Term
| ischemic effect on neurons 48h-14d: appearance, activities |
|
Definition
MACROPHAGES
gelatenous, friable, edema resolves, well demacrated necrosis |
|
|
Term
| ischemic effect on neurons 14d-30d: appearance, activities |
|
Definition
GRANULATION LIKE activity
removal of necrotic tissue |
|
|
Term
| ischemic effect on neurons 30d+: appearance, activities |
|
Definition
FLUID FILLED SPACE WITH GLIOSIS
gliosis/scar seperates it from meninges leaving DARK GRAY CAVITY |
|
|
Term
| define pseudolaminar necrosis |
|
Definition
| when gliosis and neuronal loss is not proportional |
|
|
Term
| what is the poor mans way of remembering morphology of ischemic injury on neurons |
|
Definition
red neurons
1d
inflammation: PMN->macro
1wk
granulation like
1mo
cystic space, gliosis, astrocytes |
|
|
Term
|
Definition
| vascular rupture causes direct tissue damage and secondary ischemia |
|
|
Term
| cause of subarachnoid hemorrhage |
|
Definition
| rupture of berry aneurysm |
|
|
Term
| how can you look at a brain and tell there has been a subarachnoid hemorrhage |
|
Definition
| blood pools at the bottom |
|
|
Term
| signs of subarachnoid hemorrhage 3 |
|
Definition
| sudden headache, nuchal rigidity, LOC |
|
|
Term
| LP sign of subarachnoid hemorrhage |
|
Definition
| xanthochroma (due to bilirubin breakdown) |
|
|
Term
| prognosis of subarachnoid hemorrhage |
|
Definition
| 30% have multiple, death risk increases with each |
|
|
Term
| what are berry aneurysms associated with 2 |
|
Definition
marfans
AD polycystic kidney disease |
|
|
Term
| where are the 4 common locations of berry aneurysm and their prevelance |
|
Definition
90% IN ANTERIOR CIRCULATION:
40% ANTERIOR COMMUNICATING BRANCH POINT
34$ middle cerebral
4% bifurcation of basilar |
|
|
Term
|
Definition
congenital disorder of ECM causes LACK OF MUSCULAR LAYER OF VESSEL leaving only hayline intima and internal elastic lamina allowing outpouching
rupture is caused by trauma, increase in size, hematologic change, tumor, increased iCP, straining (orgasm, pooing) |
|
|
Term
| cause of non-saccular aneurysms 4 |
|
Definition
vascular occlusion
trauma
dissection
athlerosclerosis |
|
|
Term
| location of non-saccular aneurysms |
|
Definition
| often ANTERIOR CIRCULATION due to athlerosclerosis in basilar artery |
|
|
Term
| other complications of subarachnoid hemorrhage 2 |
|
Definition
vasospasm of surrounding vessels can cause ischemia
healing causes obstruction of CSF flow and reabsorption |
|
|
Term
| cause of primary brain parenchymal hemorrhage, cellular changes |
|
Definition
HTN causes rupture of small INTRAPARENCHYMAL VESSELS and blood compresses parenchyma turns BROWN AND EDEMATOUS
fills with LIPID FILLED MACROPHAGES and astrocytes proliferate |
|
|
Term
| locations of primary brain parenchymal hemorrhage 4 |
|
Definition
basal ganglia (hemorrhage of lenticulostriates)
thalamus
pons
cerebellum |
|
|
Term
| cause of cerebral amyloid angiopathy |
|
Definition
| amyloid deposits on walls (Alzheimer's) of meningeal and CORTEX vessels weaken them and cause LOBAR HEMORRHAGES |
|
|
Term
| define vasculitis, how does it cause damage |
|
Definition
| inflammation of vessels compormises exposes endothelium and allows for clotting which causes infarct |
|
|
Term
| what type of vasculitis occurs in the brain |
|
Definition
|
|
Term
| primary angiitis: location, cellular effects 4, symptom 1, tx 1 |
|
Definition
parenchymal and subarachnoid vessels
chronic inflammation
multinucleate giant cells
granulomas
destruction of walls
symp: encephalopathy
tx: immune supression |
|
|
Term
| what is the most dangerous and most common vascular malformation in the brain |
|
Definition
| arteriovenous malformation (AVM) |
|
|
Term
|
Definition
| subarachnoid vessels extend into brain or vessels in brain rupture |
|
|
Term
| symptoms/associations of AVM 3 |
|
Definition
seizure
intraverebellar hemorrhage
subarachnoid hemorrhage |
|
|
Term
| what is the normal age range of AVM |
|
Definition
|
|
Term
| what are 4 types of AVM morphology/types |
|
Definition
hereditary hemorrhagic telegictasia
cavernous hemangioma
capillary telangiectasias
venous angioma (varices) |
|
|
Term
| what are the effects/complications/prognosis of a AVM on the body 2 |
|
Definition
large size as newborn causes high output failure when blood shunts from arteries to veins
high risk fo bleed makes them dangers |
|
|
Term
| in general, what does a AVM look like, what is it made of |
|
Definition
tangled network of vascular channels formed by enlarged vessels seperated by gliotic tissue
duplicated and fragmented internal elastic lamina or replacement of media by hyalinized CT |
|
|
Term
| hereditary hemorrhagic telegictasia: cause, sign |
|
Definition
AD mutation in TGF-B pathway
multiple AVM |
|
|
Term
| cavernous hemangioma: appearance, cellular changes, effect on vessels, 3 locations |
|
Definition
distend loosley organized vascular channels
collagenized walls without nerve tissue
vessels have low flow without shunting
cerebellum, pons, subcortical regions |
|
|
Term
| capillary telangectasias: appearance, location |
|
Definition
dilated thin walled vascular channels separated by normal brain parenchyma
pons |
|
|
Term
| venous angioma: appearance, sign |
|
Definition
aggregates of ectatic venous channels
likley to bleed and cause symptoms |
|
|
