Traumatic Brain Injury
(TBI)
Head Injury
8
million/yr in US, 1.5 million serious, .5 million hospitalized, 100,000 die,
90,000 disabled, 2,000 end up vegetative
More Head Injury Stats:
l 2-3x more males than females
l peak ages 18-24 & over 75
l 20% of those who die from head injuries don’t have a
skull fracture; skull fracture is not a good predictor of outcomes unless it is depressed
l in 2/3 death results from excessive movement of the
brain in skull
Causes of Head Injuries
l 50% in motor vehicle accidents
l 21% in falls
l 12% assaults & violence
l 10% in sports/recreational accidents
l 7% other
Sports Injuries
l About 300,000 sport-related head injuries a year in US
(9% serious)
l Sports involved (from most frequent)
» Equestrian
» Boxing
» Football, soccer, rugby
» Bicycling
» Martial arts; auto racing
» Hockey
Types of Injuries
l Concussion - transient neurologic dysfunction (altered
consciousness or LOC) but no damage visible
l Closed head injury (CHI)-skull intact; brain injured
by excessive movement
l Contusion - bruising of brain (surface blood vessels
broken, tissue swells)
l Penetrating injury or laceration - brain tissue torn
or punctured (by bullet, bone fragment)
Focal Damage to Frontal
Lobes
Floor of Skull
Coup-Contrecoup Injuries
Damage in CHIs
l at point of impact (“coup”)
l opposite point of impact (“contrecoup”)
l where brain presses or is pulled against skull or
dural partitions
l where tissue is stretched, twisted or sheared -rapid
deceleration causes diffuse axonal injury & petechia (pinpoint hemorrhages)
l tissue compressed by intracranial pressure (blood,
swelling) or fracture
Coup-Contrecoup Injuries
Increased Intracranial
Pressure
l No extra room in skull for blood, swelling
l Increased intracranial pressure presses on brain
causing symptoms, damage, and possible herniation
l Signs: change in consciousness, pupils, breathing,
motor function, headache, vomiting, seizures, personality, papilledema
Head Injury Related
Bleeding
l Epidural/extradural hematoma - most often after a blow
to side of head damages meningeal arteries. May appear lucid after initial
signs of concussion but then rapidly decline (1-2 hr) - drowsiness,
hemiparalysis, 1 pupil may dilate.
Emergency surgery to relieve growing pressure before brain herniates.
Head Injury Related
Bleeding (cont.)
l Subdural hematoma - front/back blow causes slower
bleed over days/wks
l Intracerebral hematoma - bruising of brain can cause
internal bleeding (most often frontal or temporal)
Hematomas
Epidural Hematoma
Subdural Hematoma
Craniotomy to Remove
Hematoma
Herniation Due to Pressure
l midline shift past falx cerebri
l medial temporal lobe past tentorium, causing pressure
on midbrain
l cerebellum/medulla thru foramen magnum, causing
pressure on medulla
l herniation can quickly cause coma and death
Diffuse Axonal Injury
Petechial Hemorrhages
Gunshot Thru Brain
Basal or Basilar Skull
Fracture
l Sometimes visible surface of skull may be intact but
injury has cause hairline fractures of the bottom of the skull
l Fracture may tear dura or may injure the bones of the
facial sinuses or auditory canal
l Signs: Racoon’s eyes, Battle’s sign, otorrhea,
rhinorrhea
Battle’s Sign
Possible Head Injury
Sequelae
l post-traumatic amnesia (PTA) or milder memory
difficulties
l focal losses (e.g cognitive, personality, motor etc.)
l meningitis if head was opened
l post-traumatic epilepsy
l coma
Coma & Related States
l Coma – total unconsciousness (eyes closed, can’t be
aroused, no response to pain)
l Persistant vegetative state – eye opening and periodic
wakefulness, eye movements, grimaces, grasping/groping,withdrawal from pain,
but no real awareness
l Locked-in syndrome – consciousness but almost complete
paralysis due to brainstem damage
Prevention
l wear seatbelts; use infant seats
l avoid motorcycles; wear helmits
l don’t drink excessively (& don’t drive)
l beware of hazardous falls; use ladders appropriately
l beware of assault situations; projectiles
CHIs Vary in Severity (see
Iverson link)
l Head Trauma with little or no injury
l Uncomplicated Mild Head Injury
l Complicated Mild Head Injury
l Moderate Head Injury
l Severe Head Injury
l Catastrophic Head Injury