CNS Path Quiz 6 part 2 Flashcards
3 categories of cerebrovascular disease
thrombotic
embolic
hemorrhagic
two pathophysiologic processes taking place in cerebrovascular disease?
- lack of blood supply and oxygen (ischemic)
- rupture of blood vessels (hemorrhagic)
two types of cerebral ischemia
focal (localized)- due to thrombi/emboli
global- due to cardiac arrest, hypotension
Microscopically, ischemic and infarcted cells will fail to
stain properly with vital stains such as a H. and E. stain
Macroscopically, in cerebrovascular disease the brain may appear
edematous with swollen gyri and narrowed sulci
poor demarcation between white and grey matter
global hypoxia results in
border zone infarcts
laminar necrosis
cerebral infarction aka
stroke
loss of circulation to an area of the brain
risk factors for stroke
advanced age HTN DM high cholesterol tobacco use atrial fib
while it’s hard to distinguish hemorrhagic from ischemic stroke, what sx point towards hemorrhagic?
N/V
h/a
change consciousness
ischemic stroke due to
thrombosis
emboli
systemic hypoperfusion
hemorrhagic stroke due to
intracerebral hemorrhage
subarachnoid hemorrhage
subdural hemorrhage
epidural hemorrhage
80% of strokes are which category?
ischemic
which category of stroke is more severe and results in higher mortality rates?
hemorrhagic
Approximately 50% of all stroke deaths occur within
the first 48 hours
first 12-24 hours of a stroke, neurons undergo which changes?
red neurons
dead neurons as a result of hypoxia
what changes occur after 24 hrs in a stroke patient?
neutrophil infiltration at edges of lesion
1-14 days after what changes take place in a stroke patient?
incr. macrophages
gliosis (not scars dues to lack of fibrosis)
gliosis aka
reactive proliferation of astrocytes
first response in gliosis
microgliosis (migration of macrophages and local microglia to the injury site)
gliosis eventually leads to
a dense fibrous network of neuroglia
macroscopically one can see what after 12-24 hrs?
discoloration (appears red)
softening in the affected
arterial territory with edema
most common cause of thrombotic occlusion
atherosclerosis
which vessel has the greatest degree of compromise in ischemic stroke?
middle cerebral artery
infarction due to embolism may show
punctate hemorrhages
intracerebral hemorrhage (a type of hemorrhagic stroke) is caused by what?
HTN
which imaging should be done first in a hemorrhagic stroke? why?
CT because it’s much better at picking up blood
how does hemorrhage look on CT
radio-opaque midline shift (corpus collosum)
dreaded complications of hemorrhagic stroke?
- incr intracranial pressure
- herniation
- greater risk of stroke occurs further down (brainstem or cerebellum)
cerebellar and brain stem strokes generally occur as a result of pathology where?
vertebral and basilar arteries
whats the most common cause of a subarachnoid hemorrhage?
rupture of saccular aneurysm (berry aneurysm)
what IS a berry aneurysm?
out-pouching from the circle of Willis
where’s the most common spot for a berry aneurysm to occur?
anterior communicating artery
what’s the most common type of vascular malformation?
Arteriovenous malformations
an arteriovenous malformation hemorrhage differs from a hypertensive hemorrhagic how?
AVM hemorrhage has less blood
In macroscopic appearance, they resemble a tangled network of wormlike vascular channels and have a prominent, pulsatile arteriovenous shunt with high blood flow through the malformation
arteriovenous malformation
acute hypertensive encephalophathy is characterized by
diffuse cerebral dysfunction
bleeding does not remit spontaneously, so rapid intervention is necessary
what 3 physical forces can coexist to produce head injury?
skull fractures
parenchymal injury
vascular injury
The characteristic neurologic picture of concussion includes
loss of consciousness,
temporary respiratory arrest and loss of reflexes
unequal pupil size can be a sign of brain injury (more serious than concussion)
Anisocoria
contusion (brain bruise) and laceration (tearing of brain tissue) are associated with injury to what part of the brain?
parenchymal injury
cerebral injury at the point of contact
coup
brain damage opposite the point of contact
countercoup
most common type of skull fracture?
linear skull fractures
linear fracture that occurs along sutures lines in young children
diastatic skull fracture
in skull fracture, what artery is at particular risk of injury?
middle meningeal artery
if the meningeal artery should rupture in a skull fracture, what is this called?
Epidural hematoma
rupture of veins between the brain and the superior sagittal sinus is called what?
Subdural hematoma
accumulation of blood between the dura and the arachnoid in a skull fracture is called? occurs in what part of brain?
Subdural hematoma
fronto-parietal regions of the cerebral hemispheres
accumulation of blood between the dura and skull is called?
Epidural hematoma
irreversible cessation of ALL brain function
brain death
in order to declare someone brain dead, what perimeters must be met?
- pt not in hypotensive shock
- body temp above 32 deg
- no drug intoxication or neuromuscular blockage causing coma
is an EEG showing the absence of any physiologic brain activity necessary to declare a patient brain dead?
NO
cerebral injury at the point of contact
coup
brain damage opposite the point of contact
countercoup
most common type of skull fracture?
linear skull fractures
linear fracture that occurs along sutures lines in young children
diastatic skull fracture
in skull fracture, what artery is at particular risk of injury?
middle meningeal artery
if the meningeal artery should rupture in a skull fracture, what is this called?
Epidural hematoma
rupture of veins between the brain and the superior sagittal sinus is called what?
Subdural hematoma
accumulation of blood between the dura and the arachnoid in a skull fracture is called? occurs in what part of brain?
Subdural hematoma
fronto-parietal regions of the cerebral hemispheres
accumulation of blood between the dura and skull is called?
Epidural hematoma
irreversible cessation of ALL brain function
brain death
in order to declare someone brain dead, what perimeters must be met?
- pt not in hypotensive shock
- body temp above 32 deg
- no drug intoxication or neuromuscular blockage causing coma
is an EEG showing the absence of any physiologic brain activity necessary to declare a patient brain dead?
NO
