TBI Flashcards
What is TBI?
Result of an external physical force to the brain causing transient or permanent neurological deficit
M:F TBI?
3-4:1
Age group most affected by TBI?
15-35
What are the main mechanisms of TBI?
- Focal pathology 2” contact (e.g. falls, assault)
- Diffuse pathology a/w acceleration / deceleration (e.g. traffic accident)
Brain also injured as a result of primary injury and secondary effects from the injury
What may focal brain injury cause?
- Lesion of scalp, skull and dura
- Surface contusions and lacerations to the brain
- Intracranial haematoma
What are skull fractures strongly associated with?
Development of intracranial haematoma
Where may contusions be located and what are they termed?
- Site of injury = coup
2. Opposite point of contact = contrecoup
Where are contusions more likely to be located?
Frontal and temporal lobes
Where may intracranial haematomas be located?
- Extradural: ovoid mass of blood between bone and dura
- Intradural: SAH, SDH, ICH
What are diffuse brain injuries?
Pathologies associated with acceleration / deceleration injuries.
What are diffuse brain injuries called?
Diffuse axonal injury (DAI)
What are the features of DAI?
- lesions of corpus callosum and other midline structures, parasagittal white matter, inter ventricular septum and walls of third ventricle
- Focal lesions in one or both dorsolateral sectors of the rostral brain stem
- Microscopic evidence of widespread damage to axons
What are the secondary mechanisms which may cause brain injury?
- Raised ICP
- Localised oedema around contusions
- Hypoxic damage
- Neurochemical / cellular changes
What are the types of consequences of head injury?
- Neurological impairment
- Medical complications
- Cognitive / behavioural complications
- Longer term lifestyle difficulties
What are the common neurological complications of TBI?
- Visual changes, esp diplopia CNVI palsy), altered accommodation and hemianopia
- Anosmia (40%)
- high level balance / coordination difficulties / vertigo / dizziness
- focal neuro deficits less common, related to focal trauma (e.g. assault with blunt instrument)
What are the likely medical complications of TBI?
- Spasticity
- Post traumatic epilepsy
- Heterotopic ossification
- Hydrocephalus (less common)
- Endo: SIADH and DI
- Psych e.g. depression
Type and management of spasticity post TBI?
May be generalised but usually causes focal problem.
- Rx: baclofen, botox if focal
- PT e.g. positioning, stretching