neuropathology of head trauma Flashcards
Trauma is the____ leading cause of death in the USA.
fifth
Trauma is the leading cause of death in persons under _____ of age.
44 years
Traumatic brain injury (TBI) is a contributing factor in _____of all trauma-related deaths.
a third
Approximately __% of the US population (~5 million people) living with long term disabilities as a consequence of a TBI
2
mechanical damage occurring at the moment of impact
primary brain injury
primary brain injury may also cause secondary effects effects via ______ due to ___________
secondary brain injury due to mass lesions, brain swelling, cerebral ischemia, infection, etc
Traumatic brain injury (TBI) may be caused by ______ or by______ forces.
- impact forces - inertial forces
examples of inertial forces
acceleration, deceleration, rotational forces
mechanical strain, stretching or shearing of axons
diffuse axonal injury
inertial forces like a car accident can cause diffuse injury of ____ and ____. This can lead to __________
- diffuse injury of axons and blood vessels - this can lead to diffuse brain injury
closed head injury
non-penetrating head trauma) from blunt force injury (contact injury)
is closed or penetrating head trauma more common?
closed heady injury
label the types of hemorrhages
epidural hematoma
A blood clot located between inner table of skull and dura mater in the epidural space.
most epidural hematomas are associated with a skull fracture and tearing of a meningeal ______ usually the ________
artery, the middle meningeal artery
epidural hematoma is usually associated with a _____ accident, ____ or _____
motor vehicle accident, fall, or assault
an epidural hematoma from torn artery grows quickly, causing______ and the potential for_____ herniation
mass effect
transtentorial
talk and die syndrome
About 25% of patients have a short “lucid interval” before lapsing into coma from the mass effect
between the ____ table and _____ is an epidural hematoma
inner table and dura matter
( between dura matter and bone)
describe this
epidural hematoma - lens shape
subdural hematoma
Blood clot located in potential space between dura and arachnoid. Normally, this space is occupied by the layer of dural border cells.
subdural hematoma is commonly due to tearing of a _____ by inertial forces
bridging vein
May also be due to laceration of a small leptomeningeal artery associated with an underlying brain contusion
subdural hematoma
May also occur after minor or unrecognized head injury in patients with predisposing factors
subdural hematoma
type of hematoma that is most common
subdural
subdural hematoma resulting in the Mass effect may be sufficient to cause _______ and transtentorial herniation
midline shift
onsent of acute subdural hematoma (SDH)
becomes symptomatic within 3 days of trauma
subacute subdural hematoma becomes symptomatic between _____ days and _____ of trauma
3 days and 3 weeks of trauma
onsent of chronic SDH
becomes symptomatic beyond 3 weeks after trauma
what is this
subdural hematoma
Chronic SDH is due to the failure of resorption of an acute SDH. The persisting hematoma becomes encapsulated by___________over a two–week period.
fibrovascular membranes
predisposing factors for chorinic subdural hematoma
Age-related brain atrophy, alcoholism, coagulopathy, and over-drainage of CSF by a VP shunt are predisposing factors.
Hematoma enlarges due to ________—may see old and new hemorrhage on CT scan.
re-bleeding
50% of patients recall no head trauma in this type of hemorrage
subarachnoid hemorrhage (SAH) usually accompanies ____ head injury
significant
most common cause of subarachnoid hemorrhage
head trauma
what is this image
intracerebral hemorrhage
A _______ is a cortical hemorrhage resulting from the surface of the brain making contact with the bony protuberances of the base of the skull.
contusion
A variable amount of brain necrosis ______ accompanies the brain hemorrhage
(contusion necrosis)
Remote contusions are evidenced grossly by _____-stained areas of cortical atrophy.
hemosiderin
favored sites for brain contusions
- Inferior frontal gyri, frontal and temporal poles, and the cortex above and below the Sylvian fissures
- Crests of the gyri are characteristically preferentially involved by contusions.
_____ contusions are defined as those beneath the site of impact.
“Coup”
______ contusions are defined as those opposite the site of impact.
“Contrecoup”
Coup contusions are more common with a _______
blow to the head
Contrecoup contusions are more common with a_______
fall
diffuse axonal injury
is due to widespread “shearing” of axons caused by an acceleration/deceleration injury.
Most common cause of coma following a traumatic brain injury
diffuse axonal injury
brain edema
•increases the ICP and magnifies any mass effect
Raised intracranial pressure (ICP) decreases _______ and may cause global brain ischemia
cerebral perfusion pressure
Mass lesions may cause brain ____ and death
herniation
Secondary effects of brain injury
- Brain edema → increases the ICP and magnifies any mass effect
- Raised intracranial pressure (ICP) → decreases cerebral perfusion pressure and may cause global brain ischemia
- Mass lesions → may cause brain herniation and death
- Ischemic brain injury — from systemic hypotension, raised ICP, etc.
- Infection — leptomeningitis or brain abscess from penetrating injury
- Post-traumatic epilepsy
- Chronic traumatic encephalopathy
clinical picture of chronic traumatic encephalopathy
- Emotional lability
- Personality change
- Memory impairment
- Dementia
- Pyramidal and extrapyramidal dysfunction
- Cerebellar impairment
microtubule associated protein, thought to be related to axonal disruption
Tau
chronic traumatic encephalopathy: Distinct perivascular accumulation of ____ protein in depths of sulci in neocortical gray matter
Tau
microscopic features of CTE chronic traumatic encephalopathy
- abnormal accumulation of hyper phosphorylated tau
- amyloid B
- transactive response DNA binding protein 43
Macroscopic findings of chronic traumatic encephalopathy
»Atrophy in cerebral hemispheres and cerebellum
chronic traumatic encepahloathy lobes preferentially affected
Temporal and frontal lobes
Infant presents with triad of acute encephalopathy, subdural hematoma(s), and __________
retinal hemorrhages
______ is the leading cause of traumatic death in infants.
•Abusive head trauma
Also known as “shaken baby syndrome,” “shaken-impact syndrome,” “inflicted traumatic brain injury, ” or “non-accidental head trauma in infants”
abuse head trauma in infants
If child survives shaken baby syndrome they maybe have
cognitive, language, motor, visual, and learning deficits
fractures of the skull vault are ____ common than those of the skull base
more
skull base fracture
basilar skull fracture
Battle’s sign suggest
basilar skull fracture
Complications of a calvarial skull fracture
- Depressed skull fragments may cause contusion of underlying brain (fracture contusion)
- Fracture may tear the middle meningeal artery in the dura mater, resulting in an acute epidural hematoma
Complications of a basilar skull fracture
- CSF leak from nose (rhinorrhea) or ear (otorrhea) and the associated risk of meningitis
- Risk of tearing a cranial nerve or the pituitary stalk
