Pathology of Head Injury Flashcards
(50 cards)
What is primary insult in head injury?
Focal and/or diffuse brain trauma
What are secondary insults (can result from primary insult) in head injury?
Hypotension
Hypoxia
Infection
Haematoma
How is conscious level assessed?
Glasgow Coma Scale (scored out of 15)
How does the GCS correlate with severity of head injury?
13-15 = mild injury 9-12 = moderate injury 3-8 = severe injury
Give 7 significant complications of head injury?
- Permanent physical disability
- Post traumatic epilepsy
- Intracranial infection
- Psychiatric illness
- Chronic subdural haemhorrage
- ‘Punch-drunk’ dementia
- Fatal outcome (uncommon)
What is a common site for laceration?
The scalp (because it is closely applied to the skull and tearing associated with application of force more likely to occur - anvil effect)
What do scalp lacerations commonly mimic?
An incised wound (important to differentiate as different mechanism of injury - knife)
Where may bruising/bleeding occur when not on outer surface of scalp?
May occur in the deeper layers of the scalp or between scalp and skull (particular note in infant head injury)
What are the 2 elements to the skull?
- Skull vault - frontal, temportal, occipital bone + sutures
- Skull base - anterior, middle, posterior cranial fossae
What are the 5 types of skull fracture?
Linear Depressed Comminuted (mosaic) Ring Contre-coup
Which is the simplest skull fracture?
Linear - ‘hinge’ fracture, fractures can spread along and reach suture and split suture (‘sprung’)
What does a depressed fracture commonly arise from?
Impact on protruding object or blunt force e.g. fro hammer
What are the risks from a depressed fracture?
Meningitis and post-traumatic epilepsy (fragments pushed inwards to damage meninges, blood vessels + brain)
What is a comminuted fracture?
Fragmented skull
What is a ring fracture?
Fracture line encircling foramen magnum caused by fall from height (usually land on feet but can be head)
What does a contre-coup fracture result from?
A fall onto back of head
What does a contre-coup fracture present as?
Fracturing of orbital plates; black ‘panda eyes’ classic of basal skull fractures
How are intracranial hamehorrhages named?
By their position within the skull in relation to the meninges i.e. extradural, subdural, subarachnoid
What does the accumulation of blood within the rigid skull in haemhorrage cause?
Raised ICP - results in brain compression causing symptoms like reduction in conscious level
What will ultimately occur as ICP increases without intervention (e.g. drill holes in skull)?
Death by compression of brainstem due to herniation of cerebellar tonsils into the foramen magnum
What is an extradural haemhorrage?
Bleeding occuring between the dura and skull
What do vast majority EDH arise from?
Damage to artery in association with skull fracture (80-90%); sometimes large venous channels can cause
Which artery is classically responsible for EDH?
Middle meningeal artery
Again, what does the accumulation of blood in EDH cause?
Raised ICP and associated symptoms
