Pathology Flashcards
What is normal intra cranial pressure?
0-10mmHg
Value of raised intracranial pressure
20mmHg
What is subfalcine herniation?
Herniation of cingulate gyrus under falx cerebri
What is a transtentorial herniation?
Herniation of medial temporal lobe (uncus) through tentorial notch (uncal herniation)
What is a tonsilliar herniation?
Herniation of cerebellar tonsils through foramen magnum (coning)
What is at risk in a uncal/transtenorial herniation?
Oculomotor nerve
Posterior cerebral artery
Superior cerebellar arteries
What is a duret haemorrhage?
Secondary haemorrhage into brainstem due to downwards displacement of brain
What is an extra dural haemorrhage between?
Inner table to periosteum + dura mater
What vessel is damaged in an extra dural haemorrhage?
Middle meningeal artery
What is a sub dural haemorrhage between?
Dura mater + arachnoid mater
What vessel is damaged in subdural haemorrhage?
Bridging veins
Categories of subdural haemorrhage + causes
- acute: trauma > rapid accumulation of blood
- chronic: elderly + chronic alcoholics (atrophy of brain)
Categories of subarachnoid haemorrhages + causes
- traumatic: basal skull fractures + contusions
- spontaneous: ruptured berry aneurysm, amyloid angioplasty, vertebral artery dissection, arteriovenous malformation
What are contusions?
Brain bruising
What is the most common cause of subarachnoid haemorrhage?
Ruptured berry aneurysm
What is the most common location of berry aneurysm?
Anterior cerebral artery
Who are subarachnoid haemorrhages more common in?
- Connective tissue disorders e.g. ehlers danlos syndrome
- polycystic kidney disease
Risk factor for a stroke
Hyperlipidaemia
Hypertension
Diabetes mellitus
Two categories of strokes
Ischaemic (cerebral infarct) (most common)
Haemorrhagic
What can ischaemic strokes be caused by?
Thrombotic occulsion
Embolic occulsion (most common)
What type of necrosis do you get in the brain?
Coagulative necrosis (wedge shaped)
What vessel is most affected in stroke caused by embolic occulsion?
Middle cerebral artery
Direct extension of ICA