A
traumatic brain injury occurs when an outside force impacts
the head hard enough to cause the brain to move within
the skull or if the force causes the skull to break and
directly hurts the brain.
- A
direct blow to the head can be great enough to
injure the brain inside the skull. A direct force
to the head can also break the skull and directly
hurt the brain. This type of injury can occur from
motor vehicle crashes, firearms, falls, sports,
and physical violence, such as hitting or striking
with an object.
- A
rapid acceleration and deceleration of the head
can force the brain to move back and forth across
the inside of the skull. The stress from the rapid
movements pulls apart nerve fibers and causes damage
to brain tissue. This type of injury often occurs
as a result of motor vehicle crashes and physical
violence, such as Shaken Baby Syndrome.
Definition:
Traumatic Brain Injury
`Traumatic
brain injury is an insult to the brain, not of a
degenerative or congenital nature but caused by an
external physical force, that may produce a diminished
or altered state of consciousness, which results
in an impairment of cognitive abilities or physical
functioning. It can also result in the disturbance
of behavioral or emotional functioning. These impairments
may be either temporary or permanent and cause partial
or total functional disability or psychosocial maladjustment.
Adopted
by the Brain Injury Association Board of Directors,
February 22, 1986. This definition is not intended
as an exclusive statement of the population served
by the Brain Injury Association of America.
Symptoms
A
person with a suspected brain injury should contact
a physician immediately, go to the emergency room,
or call 911 in the case of an emergency.
After
an impact to the head, a person with a brain injury
can experience a variety of symptoms but not necessarily
all of the following symptoms. This information is
not intended to be a substitute for medical advice
or examination. A person with a suspected brain injury
should contact a physician immediately, go to the emergency
room, or call 911 in the case of an emergency. Symptoms
of a traumatic brain injury include can include, but
are not limited to:
- Spinal
fluid (thin water-looking liquid) coming out of
the ears or nose
- Loss
of consciousness; however, loss of consciousness
may not occur in some concussion cases
- Dilated
(the black center of the eye is large and does
not get smaller in light)or unequal size of pupils
- Vision
changes (blurred vision or seeing double, not able
to tolerate bright light, loss of eye movement,
blindness)
- Dizziness,
balance problems
- Respiratory
failure (not breathing)
- Coma
(not alert and unable to respond to others) or
semicomatose state
- Paralysis,
difficulty moving body parts, weakness, poor coordination
- Slow
pulse
- Slow
breathing rate, with an increase in blood pressure
- Vomiting
- Lethargy
(sluggish, sleepy, gets tired easily)
- Headache
- Confusion
- Ringing
in the ears, or changes in ability to hear
- Difficulty
with thinking skills (difficulty “thinking
straight”, memory problems, poor judgment,
poor attention span, a slowed thought processing
speed)
- Inappropriate
emotional responses (irritability, easily frustrated,
inappropriate crying or laughing)
- Difficulty
speaking, slurred speech, difficulty swallowing
- Body
numbness or tingling
- Loss
of bowel control or bladder control
A
person with a suspected brain injury should contact
a physician immediately, go to the emergency room,
or call 911 in the case of an emergency.
Types
of traumatic brain injury
The
brain can receive several different types of injuries
depending on the type of force and amount of force
that impacts the head. The type of injury the brain
receives may effect just one functional area of the
brain, various areas, or all areas of the brain.
Types of traumatic brain injuries and their characteristics
are discussed below:
Diffuse
Axonal Injury
- A
Diffuse Axonal Injury can be caused by shaking
or strong rotation of the head, as with Shaken
Baby Syndrome, or by rotational forces, such as
with a car accident.
- Injury
occurs because the unmoving brain lags behind the
movement of the skull, causing brain structures
to tear.
- There
is extensive tearing of nerve tissue throughout
the brain. This can cause brain chemicals to be
released, causing additional injury.
- The
tearing of the nerve tissue disrupts the brain’s
regular communication and chemical processes.
- This
disturbance in the brain can produce temporary
or permanent widespread brain damage, coma, or
death.
- A
person with a diffuse axonal injury could present
a variety of functional impairments depending on
where the shearing (tears) occurred in the brain.
Source:
Brain Injury Source Volume 4 Issue
Concussion
- A
concussion can be caused by direct blows to the
head, gunshot wounds, violent shaking of the head,
or force from a whiplash type injury.
- Both
closed and open head injuries can produce a concussion.
A concussion is the most common type of traumatic
brain injury.
- A
concussion is caused when the brain receives trauma
from an impact or a sudden momentum or movement
change. The blood vessels in the brain may stretch
and cranial nerves may be damaged.
- A
person may or may not experience a brief loss of
consciousness (not exceeding 20 minutes). A person
may remain conscious, but feel “dazed” or “punch
drunk”.
- A
concussion may or may not show up on a diagnostic
imaging test, such as a CAT Scan.
- Skull
fracture, brain bleeding, or swelling may or may
not be present. Therefore, concussion is sometimes
defined by exclusion and is considered a complex
neurobehavioral syndrome.
- A
concussion can cause diffuse axonal type injury
resulting in permanent or temporary damage.
- A
blood clot in the brain can occur occasionally
and be fatal.
- It
may take a few months to a few years for a concussion
to heal.
Contusion
- A
contusion can be the result of a direct impact
to the head.
- A
contusion is a bruise (bleeding) on the brain.
- Large
contusions may need to be surgically removed.
Coup-Contrecoup
Injury
- Coup-Contrecoup
Injury describes contusions that are both at the
site of the impact and on the complete opposite
side of the brain.
- This
occurs when the force impacting the head is not
only great enough to cause a contusion at the site
of impact, but also is able to move the brain and
cause it to slam into the opposite side of the
skull, which causes the additional contusion.
Second
Impact Syndrome "Recurrent Traumatic Brain Injury"
- Second
Impact Syndrome, also termed "recurrent traumatic
brain injury," can occur when a person sustains
a second traumatic brain injury before the symptoms
of the first traumatic brain injury have healed.
The second injury may occur from days to weeks
following the first. Loss of consciousness is not
required. The second impact is more likely to cause
brain swelling and widespread damage.
- Because
death can occur rapidly, emergency medical treatment
is needed as soon as possible.
- The
long-term effects of recurrent brain injury can
be muscle spasms, increased muscle tone, rapidly
changing emotions, hallucinations, and difficulty
thinking and learning.
Penetration
Injury
Penetrating injury to the brain occurs from the impact of a bullet,
knife or other sharp object that forces hair, skin, bone and fragments
from the object into the brain.
- Objects
traveling at a low rate of speed through the skull
and brain can ricochet within the skull, which
widens the area of damage.
- A "through-and-through" injury
occurs if an object enters the skull, goes through
the brain, and exits the skull. Through-and-through
traumatic brain injuries include the effects of
penetration injuries, plus additional shearing,
stretching and rupture of brain tissue.
(Brumback
R. (1996). Oklahoma Notes: Neurology and Clinical
Neuroscience. (2nd Ed.). New York: Springer.)
- The
devastating traumatic brain injuries caused by
bullet wounds result in a 91% firearm-related death
rate overall.
(Center
for Disease Control. [Online August 22, 2002: http://www.cdc.gov/ncipc/didop/tbi.htm#rate,]).
- Firearms
are the single largest cause of death from traumatic
brain injury.
(Center
for Disease Control. [Online August 22, 2002: http://www.cdc.gov/ncipc/didop/tbi.htm#rate,]).
Shaken
Baby Syndrome
Shaken Baby Syndrome is a violent criminal act that causes traumatic
brain injury. Shaken Baby Syndrome occurs when the perpetrator aggressively
shakes a baby or young child. The forceful whiplash-like motion causes
the brain to be injured.
- Blood
vessels between the brain and skull rupture and
bleed.
- The
accumulation of blood causes the brain tissue to
compress while the injury causes the brain to swell.
This damages the brain cells.
- Shaken
Baby Syndrome can cause seizures, lifelong disability,
coma, and death.
- Irritability,
changes in eating patterns, tiredness, difficulty
breathing, dilated pupils, seizures, and vomiting
are signs of Shaken Baby Syndrome. A baby experiencing
such symptoms needs immediate emergency medical
attention.
(The
Shaken Baby Alliance. [Online August 22, 2002: www.shakenbaby.com])
Locked
in Syndrome
- Locked
in Syndrome is a rare neurological condition in
which a person cannot physically move any part
of the body except the eyes.
- The
person is conscious and able to think.
Vertical
eye movements and eye blinking can be used to communicate
with others and operate environmental controls.
Aquired Brain Injury
An
acquired brain injury is an injury to the brain,
which is not hereditary, congenital, degenerative,
or induced by birth trauma. An acquired brain injury
is an injury to the brain that has occurred after
birth.
An acquired brain injury commonly results in a change in neuronal activity,
which effects the physical integrity, the metabolic activity, or the
functional ability of the cell. An acquired brain injury may result
in mild, moderate, or severe impairments in one or more areas, including
cognition, speech-language communication; memory; attention and concentration;
reasoning; abstract thinking; physical functions; psychosocial behavior;
and information processing.
Adopted
by the Brain Injury Association Board of Directors,
March 14, 1997.
Symptoms
Acquired brain injury takes place at the cellular level within the
brain. Therefore, injury from acquired brain injury can effect cells
throughout the entire brain, instead of just in specific areas as with
traumatic brain injury.
Most symptoms of acquired brain injuries are very similar to that of
traumatic brain injuries; however, there are some difficulties that
are experienced more frequently or to a greater degree by persons with
acquired brain injuries. These symptoms can include:
- Cognitive
impairment- Thinking skills, especially memory
- Longer
lengths of time spent in a vegetative state
- Severe
behavior problems- Psychosis, depression, restlessness,
combativeness, hostility
- Muscle
movement disorders
Types
of Acquired Brain Injuries
Anoxic Brain Injury
- Anoxic
Brain Injury occurs when the brain does not receive
any oxygen. Cells in the brain need oxygen to survive
and function.
Types
of Anoxic Brain Injury
- Anoxic
Anoxia- Brain injury from no oxygen supplied to
the brain
- Anemic
Anoxia- Brain injury from blood that does not carry
enough oxygen
- Toxic
Anoxia- Brain injury from toxins or metabolites
that block oxygen in the blood from being used
Zasler,
N. Brain Injury Source, Volume 3, Issue 3, Ask
the Doctor
Hypoxic
Brain Injury
- A
Hypoxic Brain Injury results when the brain receives
some, but not enough oxygen.
Types
of Hypoxic Brain Injury
- Hypoxic
Ischemic Brain Injury, also called Stagnant Hypoxia
or Ischemic Insult- Brain injury occurs because
of a lack of blood flow to the brain because of
a critical reduction in blood flow or blood pressure.
Zasler,
N. Brain Injury Source, Volume 3, Issue 3, Ask
the Doctor
Causes
of acquired brain injury can include, but are not
limited to:
- Airway
obstruction
- Near-drowning,
throat swelling, choking, strangulation, crush
injuries to the chest
- Electrical
shock or lightening strike
- Trauma
to the head and/or neck
- Traumatic
brain injury with or without skull fracture, blood
loss from open wounds, artery impingement from
forceful impact, shock
- Vascular
Disruption
- Heart
attack, stroke, arteriovenous malformation (AVM),
aneurysm, intracranial surgery
- Infectious
disease, intracranial tumors, metabolic disorders
- Meningitis,
certain venereal diseases, AIDS, insect-carried
diseases, brain tumors, hypo/hyperglycemia, hepatic
encephalopathy, uremic encephalopathy, seizure
disorders
- Toxic
exposure
- Illegal
drug use, alcohol abuse, lead, carbon monoxide
poisoning, toxic chemicals, chemotherapy (not all
the time).
Levels of Brain Injury
Emergency personnel typically determine the severity
of neurological injury to the brain by using an
assessment called the Glascow Coma Scale (GCS)
to. The terms Mild Brain Injury, Moderate Brain
Injury, and Severe Brain Injury are used to describe
the level of initial injury in relation to the
neurological severity caused to the brain. There
may be no correlation between the initial Glascow Coma Scale score
and the initial level of brain injury and a person’s short or
long term recovery, or functional abilities. Keep in mind that there
is nothing “Mild” about a brain injury—again, the
term “Mild” Brain injury is used to describe a level of
neurological injury. Any injury to the brain is a real and serious
medical condition.
Mild
Traumatic Brain Injury Mild
Traumatic Brain Injury (Glascow Coma Scale score
13-15)
Mild traumatic brain injury occurs when:
- Loss
of consciousness is very brief, usually a few seconds
or minutes
- Loss
of consciousness does not have to occur—the
person may be dazed or confused
- Testing
or scans of the brain may appear normal
- A
mild traumatic brain injury is diagnosed only when
there is a change in the mental status at the time
of injury—the person is dazed, confused,
or loses consciousness. The change in mental status
indicates that the person’s brain functioning
has been altered, this is called a concussion.
Symptoms
of mild traumatic brain injury:
- Headache
- Fatigue
- Sleep
disturbance
- Irritability
- Sensitivity
to noise or light
- Balance
problems
- Decreased
concentration and attention span
- Decreased
speed of thinking
- Memory
problems
- Nausea
- Depression
and anxiety
- Emotional
mood swings
This
information is not intended to be a substitute for
medical advice or examination. A person with a suspected
brain injury should contact a physician immediately,
go to the emergency room, or call 911 in the case
of an emergency. Symptoms of Mild Traumatic Brain
Injury can be temporary. The majority of people with
Mild Traumatic Brain Injury recover after one year.
Department
of Defense and Veteran's Head Injury Program & Brain Injury Association of
America (1999). Brain Injury and You.
Horn,
L.J. & Zasler, N. (1996). Medical Rehabilitation of Traumatic Brain Injury.
Hanley & Belfus, Inc: Philadelphia, PA.
Kay,
T. Brain Injury Association of America. Mild traumatic brain injury.
Moderate
Traumatic Brain Injury (Glascow
Coma Scale core 9-12)
A moderate traumatic brain injury occurs when:
- A
loss of consciousness lasts from a few minutes
to a few hours
- Confusion
lasts from days to weeks
- Physical,
cognitive, and/or behavioral impairments last for
months or are permanent.
Persons
with moderate traumatic brain injury generally can
make a good recovery with treatment or successfully
learn to compensate for their deficits.
Department
of Defense and Veteran's Head Injury Program & Brain
Injury Association of America (1999). Brain Injury
and You.
Severe
Brain Injury (Glascow
Coma Score 8 or less)
Severe
brain injury occurs when a prolonged unconscious
state or coma lasts days, weeks, or months. Severe
brain injury is further categorized into subgroups
with separate features:
- Coma
- Vegetative
State
- Persistent
Vegetative State
- Minimally
Responsive State
- Akinetic
Mutism
- Locked-in
Syndrome
Coma
Coma
is defined as a state of unconsciousness from which
the individual cannot be awakened, in which the individual
responds minimally or not at all to stimuli, and initiates
no voluntary activities.
- Persons
in a coma appear to be asleep, but cannot be awakened
- There
is no meaningful response to stimulation.
Persons
who sustain a severe brain injury can make significant
improvements, but are often left with permanent physical,
cognitive, or behavioral impairments.
Department
of Defense and Veteran’s Head Injury Program & Brain
Injury Association of America (1999). Brain Injury
and You.
Vegetative
State (VS)
Vegetative
State (VS) describes a severe brain injury in which:
- Arousal
is present, but the ability to interact with the
environment is not.
- Eye
opening can be spontaneous or in response to stimulation
- General
responses to pain exist, such as increased heart
rate, increased respiration, posturing, or sweating
- Sleep-wakes
cycles, respiratory functions, and digestive functions
return
There
is no test to specifically diagnose Vegetative State;
the diagnosis is made only by repetitive neurobehavioral
assessments.
Giacino,
J. & Zasler, N. (1995). Outcome after severe traumatic
brain injury: Coma, the vegetative state, and the minimally
responsive state. Journal of Head Trauma Rehabilitation,
10, 40-56.
Persistent
Vegetative State (PVS)
Persistent
Vegetative State (PVS) is a term used for a Vegetative
State that has lasted for more than a month.
- The
criteria is the same as for Vegetative State
The
use of this term is considered controversial because
it implies a prognosis.
Giacino,
J. & Zasler, N. (1995). Outcome after severe traumatic
brain injury: Coma, the vegetative state, and the minimally
responsive state. Journal of Head Trauma Rehabilitation,
10, 40-56.
Minimally
Responsive State (MR)
Minimally
Responsive State (MR) is the term used for a severe
traumatic brain injury in which a person is no longer
in a coma or a Vegetative State. Persons in a Minimally
Responsive State demonstrate:
- Primitive
reflexes
- Inconsistent
ability to follow simple commands
- An
awareness of environmental stimulation
The
frequency and the conditions in which a response
was made are considered when assessing the meaningfulness
or purposefulness of a behavior.
Giacino,
J. & Zasler, N. (1995). Outcome after severe traumatic
brain injury: Coma, the vegetative state, and the minimally
responsive state. Journal of Head Trauma Rehabilitation,
10, 40-56.
Akinetic
Mutism
Akinetic
Mutism is a neurobehavioral condition that results
when the dopaminergic pathways in the brain are damaged.
Damage to these pathways results in:
- Minimal
amount of body movement
- Little
or no spontaneous speech
- Speech
which can be elicited (For example, the person
can answer a question if asked, but otherwise does
not voluntarily start saying anything).
- Eye
opening and visual tracking
- Infrequent
and incomplete ability to follow commands
- Vigilance
and agitation for Frontal Akinetic Mutism
Akinetic
Mutism is different from the Minimally Responsive
State because the lack of movement and speech with
Akinetic Mutism is not because of neuromuscular disturbance.
Giacino,
J. & Zasler, N. (1995). Outcome after severe traumatic
brain injury: Coma, the vegetative state, and the minimally
responsive state. Journal of Head Trauma Rehabilitation,
10, 40-56.
Locked
in Syndrome
Locked
in Syndrome is a rare neurological condition in
which a person cannot physically move any part
of the body except the eyes. The person is conscious
and able to think.
- Vertical
eye movements and eye blinking can be used to communicate
with others and operate environmental controls.
Brain
Death
Brain
death can result from a very severe injury to the brain.
When brain death occurs, the brain shows no sign of
functioning. The physician performs a specific formal
brain death examination.
For
information and resources about brain injury, please
contact the Brain Injury Association of America’s
Helpline at 1-800-444-6443 or email: familyhelpline@biausa.org.
Open
and Closed Head Injuries
When a person receives an impact to the head from an outside force,
it can injure the skin, skull, and the brain. Skin covers the skull.
Skin injuries can include cuts, burns, and bruising.
- A
person with skin injuries may or may not have a
brain injury.
- Conversely,
persons with a traumatic brain injury may or may
not have visible skin injuries on their head.
The
skull is hard and composed of bone. The skull covers
the brain.
- The
skull is hard and protects the soft brain inside
it.
- The
inside of a skull is rough.
- The
inside of the skull can contribute to brain injury
if an outside force causes the brain to move from
its normal position and rub across the rough skull.
Open
Head Injury
If the force that hits a person's head is great enough,
the skull can fracture or become out of place. When
this happens, the person is described as having an "open head injury".
This terminology is referring to the condition of
the skull and not the brain. Separate terms are used
to describe the condition of the brain. For example,
a person may be described to have an open head injury
with a severe traumatic brain injury.
- When
the head receives an impact from an outside source,
if the brain is injured the brain may swell.
- If
the skull is fractured or displaced, this can allow
the brain room to swell and can assist in reducing
the squeezing of brain tissues.
- If
the skull is fractured or displaced, bone fragments
from the skull can enter the brain and cause further
injury.
- Because
the skull is damaged or open, it cannot protect
the brain as it did before. The once protected
brain is now exposed, which leaves it vulnerable
to infections and further injury.
- Persons
with an open head injury may be assigned to wear
a helmet to protect the exposed brain from impact
and further injury.
- If
a piece of the skull is displaced during traumatic
injury, that piece of skull may be surgically replaced
at a later date. An artificial skull piece may
be applied also.
Types
of Open Head Injuries
The following are terms used to describe types of skull fractures that
can occur with open head injuries:
Depressed Skull Fracture - The broken piece of skull
bone moves in towards the brain
Compound Skull Fracture - The scalp is cut and the
skull is fractured
Basilar Skull Fracture
- The
skull fracture is located at the base of the skull
(neck area) and may include the opening at the
base of the skull
- Can
cause damage to the nerves and blood vessels that
pass through the opening at the base of the skull
Battle's
Sign
- The
skull fracture is located at the ear's petrous
bone.
- This
produces large "black and blue mark" looking areas
below the ear, on the jaw and neck.
- It
may include damage to the nerve for hearing.
- Blood
or cerebral spinal fluid may leak out of the ear.
This is termed "CSF Oterrhea".
Racoon
Eyes
- The
skull fracture is located in the anterior cranial
fossa.
- This
produces "black and blue" mark looking areas around
the eyes.
- Cerebral
spinal fluid may leak into the sinuses. This is
termed "CSF Rhinorrhea".
- Nerve
damage for the sense of smell or eye functions
may occur.
Diastatic
Skull Fracture
- The
skull of infants and children are not completely
solid until they grow older.
- The
skull is composed of jigsaw-like segments (cranial
fissures) which are connected together by cranial
sutures.
- Skull
fractures that separate the cranial sutures in
children prior to the closing of the cranial fissures
are termed "diastatic skull fractures".
Cribiform
Plate Fracture
- The
cribiform plate is a thin structure located behind
the nose area.
- If
the cribiform plate is fractured, cerebral spinal
fluid can leak from the brain area out the nose.
Closed
Head Injury
When a person receives an impact to the head from
an outside force, but the skull does not fracture
or displace this condition is termed a "closed head injury".
Again, separate terminology is added to describe
the brain injury. For example, a person may have
a closed head injury with a severe traumatic brain
injury.
- With
a closed head injury, when the brain swells, the
brain has no place to expand. This can cause an
increase in intracranial pressure (the pressure
within the skull).
- If
the brain swells and has no place to expand, this
can cause brain tissues to compress, causing further
injury.
- As
the brain swells, it may expand through any available
opening in the skull, including the eye sockets.
When the brain expands through the eye sockets,
it can compress and impair the functions of the
eye nerves. For instance, if an eye nerve, Cranial
Nerve III, is compressed, a person's pupil (the
dark center part of the eye) will appear dilated
(big). This is one reason why medical personal
may monitor a person's pupil size and intracranial
pressure.
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