Brain Tumours Flashcards
(63 cards)
general presentation of brain tumours
- progressive focal neurological deficit
- motor weakness
- raised ICP features (headache)
- seizures
acute onset of symptoms?
tumour can cause eg if starts bleeding
name 4 supratentorial herniations
what happens in an uncal herniation
the medial part of the temporal lobe (uncus) herniates inferiorly to the tentorium cerebelli
which type of herniation can damage CNIII
uncal - ipsilateral fixed blown pupil
describe ICP headache
- awaken them from sleep
- exacerbated by couging, sneezing,bending
- worse on lying down
raised ICP features
- vomiting without nausea
- ocular palsy
- back pain
- papilloedema - bilateral
- alteredlevel of consciousness
- seizures
cushings triad
Cushing’s triad: increase in systolic and pulse pressure, bradycardia and irregular respiration
- Raised ICP to the point where it exceeds MABP, this causes the arterioles in the brains cerebrum to become compressed. Compression results in cerebral ischaemia
- Activation of sympathetic and parasympathetic nervous system. At this stage sympathetic is activated more and causes hypertension and tachycardia
- Baroreceptors in the aortic arch detect this and trigger a parasympathetic response via CNX, induces bradycardia
- Bradycardia may be caused due to direct mechanical distortion of CNX
- Increased pressure on the brainstem (control of breathing) results in irregular respiratory pattern
presentation of frontal lobe problem
- contralateral weakness due to deficit in M1
- personality changes - disinhibition and cognitive slowing
- urinary incontinence due to disruption of micturition inhibition centre
- gaze abnormalities - frontal eye field involvement
- expressive dysphasia/aphasia if Brocas area on left is involved
- seizures
presentation of temporal lobe problem
- memory deficits
- receptive aphasia/dysphasia for left sided lesions if Wernickes area involved
- contralateral superior quadrantopia
- seizures
presentation of parietal lobe problem
- contralateral weakness and sensory loss due to deficit in S1
- contralateral inferior quadrantopia
parietal lesion on dominant lobe presentation
dyscalculia, dysgraphia, finger agnosia, left right disorientation if dominant lobe affected –> gerstmann syndrome
parietal lesion on non dominant lobe presentation
neglect (not aware of one side of the body), dressing and constructional apraxia
occipital lobe lesion presentation
contralateral homonymous hemianopia, visual hallucinations (V1)
cerebellum lesions presentation
- ipsilateral ataxia
- n and v
- dizzines and vertigo
- slurred speech
- intention tremor
what does toe walking in children indicate
cerebellar problem
very first investigation
fundoscopy to check for papilloedema
imaging
- CT is done first - quickest and widely available
- MRI gives better tissue definition and can be used to grade tumours
what imaging is good for bleeds
CT for acute bleed, MRI for chronic/old bleeds
bleed on left, infarct on right
imaging in children
avoid CTs as they do a lot of harm, MRI is preferred
what should be suspected when an older person presents with possible brain tumour
metastases - always take a cancer history! (haemoptysis, melaena, change in bowel habits, PR bleeding)
what are the characterstics of grade I tumours and who do they occur in
- slow growing, benign
- children and YP
pilocytic (low grade I tumours) - who gets them
children and young adults
pilocytic astrocytoma - pathology
bipolar cells with long hair like projections
