Flashcards in Pathology of Head Injury Deck (19):
What is the medical word for a bruise?
What causes contusions?
Blunt force - capillaries are ruptures and blood oozes out into tissues - subcutaneous layer and muscle
What does two black eyes normally indicate?
Blood can track within looser tissues. When someone presents with two black eyes it is unlikely to be two separate blows. Instead, immediate suspicion of an injury further up or tracking from somewhere deep in the skull.
What are abrasions?
Injuries to superficial part of the skin. scratches and grazes. Skin is affected by tangential blunt force. Might be a bit sore, bleed a little bit. Heal usually without scarring because deeper structures are not damaged
What is the difference between an incision and a laceration?
Incision - sharp force injury, object causes cutting of the skin
Laceration - tear / split in the skin as a result of a blunt force injury.
What are ring fractures?
When the skull fractures in a ring around the bone
Which part of the skull tends to break in a ring fracture?
Skull tends to break at sutures or where softer bone meets harder bone, for example when the petrous part of the temporal bone meets the skull
What is a fissure fracture?
Energy dissipates from the point of impact - smaller fracture as a result of blunt force.
What is a hairline fracture?
Barely visible fracture affecting only the outer layer of the bone. Often requires no treatment
What is a depressed fracture?
A little piece of the bone has been pushed inward. Example of a hammer hitting the skull, leaves indent of the shape of the hammer - important for forensic scientists.
Which meningeal layer is separate and not closely applied to the other two layers of meninges?
Where do bridging veins travel?
Travel from arachnoid through the dura and into the venous sinuses
What causes epidural haemorrhages?
Caused by bleeding arteries MMA, as part of the head injury. 90% of people with epidural haemorrhage also have a skull fracture.
May die within several hours but they don't always fall unconscious!
What percentage of subdural haemorrhages are not as a result of skull fracture?
What causes subdural haemorrhages?
Dura moves in relation to the skull - veins that traverse the subdural space stretch and they burst. They bleed. Accumulation of venous pressure in the subdural space. Subdural haematoma. Result of the moving head against a non-moving force.
What is a cortical contusion?
Direct insult to the brain
What is a coup?
A deceleration brain injury, where the head strikes, a contusion occurs there. These people’s brains will often have further cortical contusion diametrically opposite where the first force was. (Called a contrecoup)
What natural causes intracerebral haemorrhages?
Natural disease e.g hypertensive, AV malformations, amyloid angiopathy - makes the vessels weak.