25. Neuropath: Trauma Flashcards
what are the high and low scores for the GCS?
3-15
what types of responses does the GCS take into account?
eye response, verbal response, motor response
define concussion
reversible loss of neuronal function.
totally reversible, transient, may be associated with brief LOC or postural tone.
define contusion
direct bruising of the brain, disruption of the brain parenchyma
early v later symptoms of concussion?
early: HA, N/V, dizziness
late: low grade HA, blurry vision, hearling loss, irritability, poor attention….
Primary v secondary damage to the brain?
primary: direct damage to the brain, immediate. laceration, fracture, contusion, etc
secondary: not immediate, sequelae of trauma, can be more devastating. ischemia, hypoxia, swelling, infection.
diffuse axonal injury: primary or secondary?
primary. occurs at time of trauma
open v closed CNS trauma?
open: skull or skin is broken, exposed
closed: no exposure
define galea
dense, tough collagenous tissue that sits on a layer of CT that is right on the periosteum
sub-galeal hematoma?
blood collects in loose CT between galeal layer and skull.
what is a site of fracture that can open up the MMA?
temple area, where there is a cranial suture line. MMA runs in the dura right under that, and a fracture can rip open the artery –> epidural hematoma.
what are included in the category of focal injuries?
contusions, lacerations, hematomas, focal damage due to expanding masses.
where do contusions tend to do damage? what happens there?
on the crowns of the gyri. can be punctate hemorrhages, then clot off, then ischemia and tissue dies. scarring may cause later seizures.
where are contusions likely to occur?
anterior/undersurfaces of the frontal lobe and temporal lobes.
are the sulci affected by contusions?
not usually; usually it is the crowns of the gyri and tissue immediately surrounding.
what is it called when dead tissue is removed from the location of a contusion?
plaques jeunes. brain matter looks constricted, tan in color.
what else will cause plaques jeunes?
nothing except trauma. (not inflammation, infarction, tumor)
why does the brain tend to sustain coup-counter coup injuries?
it is not well attached to the skull, has a lot of room to slosh around.
subarachnoid bleeding that is traumatic is usually associated with what?
contusions, penetrating injuries.
subarachnoid bleeding that is non-traumatic is usually associated with what?
rupture of a berry aneurysm
Epidural hemorrhage is associated with what kind of trauma?
fracture to lateral surface of skull, damaged MMA.
epidural hemorrhage: blood is under high or low pressure?
usually a broken artery; high pressure.
epidural: the blood collects between what layers?
skull and dura
subdural: blood collects between what layers?
dura and arachnoid.
epidural: blood collects quickly or slowly?
quickly; within minutes to hour.
epidural: shape of accumulation? ends at sutures or not?
lens-shaped (like a clam). stops at suture lines where dura is tacked to skull.
subdural hemorrhage: shape of accumulation? ends at sutures or not?
crescent shaped. does not end at suture lines.
subdural: what kind of bleed? fast/slow?
venous (usually bridging veins). slow bleed. may not present for a few days.
subdural: complications?
if continues to bleed, can get brain shift and subfalcine herniation.
both epidural and subdural: tx? sequelae?
tx is neurosurg. if blood removed, brain will shift back to normal location.
the movement of a bullet in the skull depends on what two factors?
caliber of the bullet and its velocity.
what are some sources of diffuse damage to the brain?
diffuse axonal injury, brain swelling, hypoxia-ischemia.
definition of diffuse axonal injury
widespread damage to axons within the CNS that results from severe acceleration or deceleration of the head. you get rips to the axons due to shear force.
what is the most common movement that will result in diffuse axonal injury?
rotation. think of spinning a bowl of jello and stopping it quickly.
with diffuse axonal injury, what types of pathological process happens to the axon?
shear, like Wallerian degeneration
what happens to the still-viable end of the axon after it is sheared in diffuse axonal injury?
it will swell –> axonal spheroid.
diffuse axonal injury: associated with what injuries (specific types of accidents)
car accidents, falls.
after DAI, how do most patients present?
comatose
DAI: patient appearance, and progression?
Most patients are comatose immediately after injury, do not experience a lucid interval, and remain unconscious, vegetative, or at least severely disabled until death.
DAI: occurs mainly in what areas of the brain? why those locations?
white matter: corpus callosum, walls of 3rd ventricle, dorsolateral surface of brainstem, periaqueductal grey matter. these are the locations where the brain is attached, where twisting movement will be especially damaging.
what is the mortality rate with DAI?
15% with mild DAI; 65% if severe.
time course of DAI?
4-5 hours: axonal accumulation of beta-amyloid precursor protein
12-24 hrs: axonal varicosities evident on H&E
24h-2months: axonal swelling and microglial nodules
long-term: wallerian degeneration, atrophy.
axonal spheroids will remain for years
diffuse edema: ipsilateral due to what? bi-hemispheric in children due to what?
ipsilateral: subdural hemorrhage
children: swelling due to trivial trauma, could be due to abnormal vasoregulation
diffuse hypoxic brain damage is a combination of what factors?
brain shifts, raised ICP, systemic hypoxia, arterial spasm
see ischemic changes often where?
at arterial boundary zones - get hypoxia and subsequent ischemia at the outer reaches of arterial perfusion.
why is it easy for kids to get shaken baby syndrome?
head relatively large on body, poor neck muscles
what are clues to shaken baby syndrome?
retinal hemorrhage, kiddo may present with coma, inconsistent history/physical, there may or may not be external head trauma.
