Histopathology 19: Cerebrovascular Disease And Trauma Flashcards
What are the 2 types of hydrocephalus ?
Non-communicating
Communicating
What is the main cause of non-communicating hydrocephalus ?
The choroid plexus gets stuck in the cerebral aqueduct blocking csf flow
What is a common cause of communicating hydrocephalus?
Meningitis infection- causes inflammation of the meninges which blocks csf reabsorption into the venous sinuses
What are the 3 main types of herniation in the brain ?
- Subfalcine herniation
- uncal herniation (medial temporal lobe down through the tentorial notch)
- Tonsillar herniation (coning)- cerebellum is pushed through the foramen magnum
What features can be seen on histology suggesting AVM (atrioventricular malformation) ?
Complex intertwining vessels
What is the characteristic sign of Cavernous Angioma on MRI ?
Target sign on T2 weighted MRI
What is a non-traumatic Intra-parenchymal haemorrhage ?
Haemorrhage into the brain parenchyma due to rupture of a small intraparenchymal vessels
Most commonly into the basal ganglia
What is the most common cause of non-traumatic intra parenchymal haemorrhages ?
Hypertension
With which symptoms/signs can a fissure fracture present ?
Otorrhoea- CSF fluid leaks out of the ears
Rhinorrhoea- CSF fluid leaks out of the nose
Battle sign and raccoon eyes
Rotational traumatic brain injury tend to cause damage to which structures in the brain ?
Midline structures - corpus callosum, rostral brainstem, septum pellucidum
Describe the features of subarachnoid haemorrhage ?
- Haemorrhage in the subarachnoid space.
- Caused by ‘berry’ aneurysm, hypertension, trauma, AVM - severe ‘thunder clap’ headache radiating to the occiput - associated with polycystic kidney disease, coarctation of the aorta
Describe the features of extradural haemorrhage ?
- Bleed above the dura due to damage to the middle meningeal artery
- associated with severe trauma and fracture to the pterion
- subsequent lucid interval.
Describe the features of Intracerebral haemorrhage (haemorrhage stroke) ?
- Caused by hypertension and arteriovenous malfor- mations.
- Hypertension may lead to either hyaline arteriosclerosis or Charcot–Bouchard aneurysms.
Describe the features of subdural haematoma ?
- Bleed between the dura and arachnoid due to an acute tear in bridging veins.
- caused by trauma.
- features of raised intracranial pressure (headaches, confusion, nausea and vomiting), altered mental state
- Insidious onset usually taking 48 hours
what are 2 types of cerebral oedema
VASOGENIC - disruption of the BBB
CYTOTOXIC - secondary to cellular injury (eg hypoxia. ischaemia)
cerebral oedema on MRI
loss of gyri
describe the route CFS takes
choroid plexus pumps out CSF
goes from lateral ventricles - intraventricular foramina - 3rd ventricle
cerebral aqueduct - 4th ventricle
medulla - central canal
subarachnoid space
CSF goes via arachnoid granulations - returns to systemic circulation
normal ICP
7-15mmHg in a supine adult
increased pressure causes herniation
features of non-traumatic intra-parenchymal haemorrhage
haemorrhage into the brain parenchyma due to rupture of small intraparenchymal vessels
common in basal ganglia
hypertension in 50%
presents as: severe headache, vomiting, LOC, focal neurological signs
presentation of AV malformations
haemorrhage
seizures
headache
focal neurological deficits
occur under high pressure causing a massive bleed
features of cavernous angiomas
well-defined malformative lesion composed of closely packed vessels with no parenchyma interposed between the vascular spaces
presents as: headache, seizures, focal deficits, haemorrhage
tend to occur at lower pressure
features of sub-arachnoid haemorrhages
rupture of a berry aneurysm
most in the inter-carotid bifurcation
highest risk of rupture when 6-10m in diameter
presents as: sudden onset severe headache, vomiting, LOC
features of cerebral infarction
tissue death due to ischaemia
cerebral atherosclerosis = most common cause
especially affects the carotid bifurcation or the basilar artery
largest area supplied by middle CA
types of head trauma
missile + non-missile
acceleration and deceleration
focal or diffuse
what are contusions
when the brain collides with the internal surface of the skull
causes bruising of the surface
if this causes rupture of the pia mater = a laceration
what is a diffuse axonal injury
occurs at the moment of injury
shear and tensile forces cause damage to the axons
midline structures particularly affected
