Pathology of head injury Flashcards
What percentage of head injuries result in serious permanent neurological deficit?
0.1%
Name some primary insults in head injury.
Focal brain tumour
Diffuse brain tumour
Name some secondary insults in head injury.
Hypotension
Hypoxia
Infection
Haematoma
What GCS score would indicate a mild head injury?
13-15
What GCS score would indicate a moderate head injury?
9-12
What GCS score would indicate a severe head injury?
3-8
What is “punch -drunk” dementia?
Dementia originating from repeated concussion or other head trauma
Why is the scalp such a common site for lacerations?
It is closely applied to the skull
What is a linear skull fracture?
Runs from top/side towards base
Commonly results from falls onto side/head
What is a depressed skull fracture?
Focal impact which may push fragments inside
Often damages meninges, blood vessels, brain
What is a comminuted fracture?
Fragmented
What is a ring fracture?
Fracture encircles the base of the skull
Usually results from falls from height
Spine and skull base forced together
What is a contre-coup fracture?
Fracture of orbital plates
Usually from falling backwards and hitting the back of the head
How does intracranial haemorrhage lead to tonsillar herniation?
Accumulation of blood - Raised ICP - Compression of brain - Compression increases to the point that the cerebellar tonsils herniate through the foramen magnum - Death
Which artery classically causes extra-dural haemorrhage?
Middle meningeal
What is an often misleading feature of extra-dural haemorrhage
Patients may under-go a lucid period where they appear to be recovering only to rapidly deteriorate later
Where do sub-dural haemorrhages occur?
Between the dura and arachnoid mater
Which blood vessels usually cause sub-dural haemorrhage?
Bridging veins passing from brain surface to large venous channels in the brain
Rotational forces may tear these vessels
Where do subarachnoid haemorrhages take place?
Between arachnoid mater and brain
What is often the cause of a subarachnoid haemorrhage?
Ruptured cerebral aneurysm
Often seen in association with cerebral contsusions (bruising)
What is diffuse axonal injury?
Tearing of nerve fibres in the white matter of the brain
What are some common causes of diffuse axonal injury?
High force rotational acceleration
RTAs
Falls from height
