Neuro Flashcards
2 causes of cerebral oedema
vasogenic - dsiruption of BBB
cytotoxic - 2ry to cellular injury i.e ischaemia, hypoxia
consequences of cerebral oedema
raised ICP
loss of gyri and sulci
what is communicating hydrocephalus
impaired reabsorption of CSF into venous sinuses
- can be caused by meningitis disrupting subarachnoid space
what is non-comm hydroceph
obstruction of CSF flow
- can be caused by bits of choroid plexus in the aqueduct
main consequence of raised ICP
herniation of the brain
tonsillar herniation
pushes cerebellum through foramen magnum into the medulla
subfalcine herniation
pushes brain more towards one side, under the falx cerebri (splits into two halves)
transtentorial herniation
separates cerebrum and brainstem (tentorium cerebelli)
interruption to cerebral blood flow which leads to focal neurological sx. lasts >24 hours or results in death. vascular origin.
stroke
temporary interruption to cerebral blood flow leading to amaurosis fugax, carotid bruits. transient loss of vision.. symptoms usually last <5min, will resolve within 24 hours.
TIA
% of patients with TIA who suffer from significant imfarct within 5 years
1/3
‘warning’ strokw
rupture of small blood vessels, most commonly in the basal ganglia, leading to headache, LOC, vomiting and focal neuro. HTN in 50%, charcot bouchard microaneurysms may be present.
intraparenchymal haemorrhage
dense accummulations of blood vessels which cna occur anywhere in the brain. can present in 20-50yos with severe headache, seizure, LOC and focal neuro.
high pressures mean there is high mortality and morbidity associated.
AVM
85% of these haemorrhages occuras a result of rupture of berry aneurysms.
risk of rupture high when diameter >6-10mm.
presents with sudden onset thunderclap headache, loc and vomiting.
SAH
rx with clip or coil
traumatic injury leading to rapid arterial bleed, lucid interval then LOC.
extradural haemorrhage
due to middle meningeal artery rupture
prev history of minor trauma. slow venous bleeding often seen in eldery or alcoholics, associated with brain atrophy. present with fluctuations in consciousness.
subdural haemorrhage
primary cause of 70-80% of stroke
atheroma
most common site of thrombosis
middle cerebral artery
vascular territory of MCA
lateral areas of the brain
vascular territories of PCA
posterior and inferior temple
ACA
midline to parieto-occipital sulcus
contraleteral hemiplegia, weakness of the lower face, ataxia
MCA
slowness, lack of spontaneity, incontinence, contraleteral lower limb weakeness
ACA
visual deficits, ataxia
PCA
transient loss of consciousness and paralysis with recovery in hours or days
concussion
single largest cause of death in <45s
traumatic brain injury
vegetative state, post traumatic dementia
diffuse axonal injury
otorrhoea, rhinorrhoea, racoon eyes, battle sign
base of skull fractures, periorbital fractures
bruising tht occurs due to brain impact with the skull. front = coup, back = contracoup. pia mater can be torn.
contusions
laceration if pia mater torn
most common sites of diffuseaxonal injury
corpus callosum, rostral brainstem
nb - same thing as chronic traumatic encephalopathy
B-amyloid plaques, TAU proteins and neurofibriilary tangles
alzheimers disease
a-synuclein on immunostaining. nigral striatal defects
parkinsons disease
TAUopathy with TAU+ve deposits in the frontal lobe
fronto-temporal atrophy, marked gliosis and neuronal loss
picks disease
non tau+ve frontotemporal demential with unilateral atrophy
progranulin
Braak staging
used in PD and alzheimers
apart from parkinsons what other disease w parkinsonism is associated with a-synuclein
lewy body dementia
multiple systemic atrophy
proteins associated with frontotemporal dementia
TAU TDP and FUS
brain tumour associated with NF-2. focal neuro sx
meningioma
brain tumour with hydrocephalus (tumour in ventricles)
ependymoma
indolent childhood brain tumour. rosethal fibres (hairy)
pilocytic astrocytoma
soft, gelatinous tumour with some calcifications
oligodendoma
severe grade 4 brain tumour with high mortality
glioblastoma multiforme
a-synuclein and ubiquitin
lewy body dmeentia
corticobasal degen - pathyological protein
tau
when in doubt guess tau
