Trauma Flashcards
The ___________ of the brain for functional repair are
major determinants of the consequences of CNS trauma.
anatomic location of the lesion and the limited capacity
Injury of several cubic centimeters of
brain parenchyma may be____________
, severely disabling),
or fatal ______________
- clinically silent (e.g., in the frontal lobe)
- (in thespinal cord)
- (in the brainstem)
The physical forces associated with head injury may result in_________, ______ and __________ ; all three can coexist.
- skull fractures,
- parenchymal injury,
- and vascular injury
The magnitude and distribution of a traumatic
brain lesion depend on the _______________, ____________ and __________ . A blow to the head may be penetrating or
blunt; it may cause either an open or a closed injury .
- shape of the object causing the trauma,
- the force of impact,
- and whether the head is in motion at the time of injury
A fracture in which bone is displaced into the cranial cavity by a distance greater than the
thickness of the bone is called a _____________
.
displaced skull fracture
The thickness of the cranial bones
varies; therefore, their resistance to fracture differs greatly.
Also, the relative incidence of
fractures among skull bones is related to the pattern of falls.
When an individual falls while
awake, such as might occur when stepping off a ladder, the site of impact is often in the
_________
occipital portion of the skull;
in contrast, a fall that follows loss of consciousness, as might follow
a syncopal attack, commonly results in a______
frontal impact.
Symptoms referable to the lower cranial
nerves or the cervicomedullary region,and thepresence of orbital or mastoid hematomas
distant from the point of impact, raise the suspicion of a ____________, which typically
follows impact to the occiput or sides of the head.
CSF discharge from the nose or ear and
infection (meningitis) may follow
basal skull fracture
. The kinetic energy that causes a fracture is dissipated at a
fused suture; fractures that cross sutures are termed______.
With multiple points of impact or
repeated blows to the head, the fracture lines of subsequent injuries do not extend across
fracture lines of prior injury.
diastatic
PARENCHYMAL INJURIES
- Concussion
- Direct Parenchymal Injury
- Diffuse Axonal Injury
__________ is a clinical syndrome of altered consciousness secondary to head injury typically
brought about by a change in the momentum of the head (when a moving head is suddenly
arrested by impact on a rigid surface).
Concussion
“Concussion, from the Latin concutere (“to shake violently”) or concussus (“action of striking together”
What is the characteristic neurologic feature of concussion?
The characteristic neurologic picture includes
- instantaneous onset of transient neurologic dysfunction, including loss of consciousness,
- temporary respiratory arrest, and loss of reflexes. Although neurologic recovery is complete,
- amnesia for the event persists.
- The pathogenesis of the sudden disruption of neurologic
- function is unknown; it probably involves dysregulation of the reticular activating system in the
- brainstem.
- Postconcussive neuropsychiatric syndromes, typically associated with repetitive injuries, are well recognized.
_______ and______are lesions associated with direct parenchymal injury of the brain
- Contusion
- and laceration
,
Direct parenchymal injury is either through transmission of kinetic energy to the brain and bruising analogous to what is
seen in soft tissues __________ or by penetration of an object and tearing of tissue____________
- (contusion)
- (laceration).
In direct parenchymal injury what are most susceptible, since this is
where the direct force is greatest.
crests of gyri
The most common locations for contusions correspond to the
most frequent sites of direct impact and to regions of the brain that overlie a rough and
irregular inner skull surface, such as the _____________ and _________
Contusions are less frequent over the occipital lobes, brainstem, and cerebellum unless
these sites are adjacent to a skull fracture (fracture contusions).
frontal lobes along the orbital ridges and the temporal
lobes.
Multiple contusions involving the inferior surfaces of frontal lobes, anterior
temporal lobes, and cerebellum.
B, Acute contusions are present in both temporal lobes, with
areas of hemorrhage and tissue disruption (arrows).
Remote contusions are present on
the inferior frontal surface of this brain, with a yellow color (associated with the term plaque
jaune).
A person who suffers a blow to the head may develop a contusion at the point of contact ____________-) or a contusion on the brain surface diametrically opposite to it (______________).
- (a coup injury)
- **a contrecoup injury) **
Since their macroscopic and microscopic appearance in Direct parenchymal injury is indistinguishable, the _________________
distinction
between them is based on forensic identification of the point of impact and the circumstances
attending the incident.
In general, if the head is immobile at the time of trauma, only a ___________
injury is found.
coup
If the head is mobile, both __________ may be
coup and contrecoup lesions
Whereas
the coup lesion is caused by the ____________,
y
the
contrecoup contusion is thought to develop when the brain strikes the opposite inner surface of
the skull **after sudden deceleration. found. **
Sudden impacts that result in violent posterior or lateral hyperextension of the neck (as occurs
when a pedestrian is struck from the rear by a vehicle) may avulse the pons from the medulla or
the medulla from the cervical cord, causing instantaneous death.
When seen on cross-section, contusions are________________
wedge shaped, with the broad
base lying along the surface, deep to the point of impact