Flashcards in Neuroradiology and Brain Tumours Deck (66):
1
what can cause a headache due to raised ICP
mass, bleed, hydrocephalus, venous thrombosis, infection, oedema
2
what is CT good for
bony detail
spatial resolution
good with emergency/ ICU equipment
fast
3
what is CT bad for
soft tissue
detail
contrast not as good as MRI
high radiation
4
what is dark and light on CT
white things more dense
darkest thing is air
5
what is MRI good for
contrast
soft tissue resolution
depiction of anatomy
marrow and cord pathologies
6
what is MRI bad for
less bony detail
less spatial resolution
not compatible with equipment/ implants
not as quick- need patient cooperation
7
what are the different types of MRI
T1 and T2
T1
-fat, methemoglobin (subacute haematoma), mineral deposition, melanin, contrast material = bright/ hyperintense
-water, air= dark/ hypointense
GREY MATTER WILL BE DARK
T2
(two W's= water white)
-water, air= bright
-fat and 4 m's= dark
GREY MATTER WILL BE LIGHT
T2 flare
form of T2 (grey matter bright) that removes brightness of CSF in the image to look for oedema in the brain
GREY MATTER BRIGHT, CSF DARK
8
does white or grey matter have more myelin
white matter- will be dark in T2, bright in T1 MRI
9
what scan if you suspect an infarct in the brain
MRI (if blood vessel not flowing will show up white)
10
what scan for a brain haemorrhage
CT sensitive for acute haemorrhage but sensitivity lessens with time
time doesn't matter in MRI
if haemorrhage look for aneurysm with CT angiography
11
what vascular abnormality has a popcorn appearance on imaging
cavernoma (cluster of abnormal blood vessels)
12
what scan is used in acute stroke
CT- shows loss of distinction between grey and white matter
13
what imaging is used in all strokes
diffusion weight image
14
what is the hallmark for trauma imaging
CT
15
what can a haematoma in the brain cause
mid line shift, herniation
16
what type of dural haematoma will affect the shape of brain more
extra dural- sub dural can spread further across the brain, extra will create a convex shape
17
when will a tumour enhance with contrast
if vascular in brain only when high grade or if arises from dura (BBB)
18
what does low density around hydrocephalus on imagine mean
oedema in brain
19
what does demyelination look like on CT (T2 and flare)
predominantly affects white mater, inflammation around small venules and veins, lesions on the white matter. CT T2 and flare
20
what is an example of an non infective imflammatory brain condition
demyelination- MS
21
what are intrinsic or extrinsic brain tumours
within our outside of brain parenchyma
22
what are the most common presentations of brain tumours
progressive neurological deficit
motor weakness
headache
seizures
23
how can a tumour increase ICP
mass
oedema mass effect
blockage of CSF flow
haemorrhage
24
what symptoms does raised ICP cause
headache, vomiting, mental changes, seizures
if uncal herniation can cause blown pupil if compresses on oculomotor nerve
25
what are the types of brain herniations
cingulate (subflacine)
central (trans tentorial)
transcalvarial
uncal
upward cerebellar/ transtentorial
downward cerebellar (tonsillar)
26
what type of headache should make you think of brain tumour
worse in morning- wakes them up
increased with coughing/ leaning forward
may be associated with vomiting or symptoms similar to tension headaches/ migraines
27
what do you do if there is scary headache symptoms
always do fundoscopyto look for papilloedema
28
why do tumours cause headaches
raised ICP
invasion/ compression of dural/ blood vessels/ periosteum
double vision
difficulty focusing
extreme hypertension (cushings triad of raised ICP)
psychogenic
29
what does the parietal lobe do
processes sensory input
sensory discrimination
body orientation
primary somatic area
secondary somatic area
30
what does werknickes area do
language comprehension
31
what does the occipital lobe to
visual reception area
visual interpretation
32
what does the cerebellum do
coordination and control of voluntary movement
33
what does the brainstem do
breathing, digestion, heart control, blood vessel control, alertness
34
what does the temporal lobe do
auditory reception area
expressed behaviour
receptive speech
memory/ information retrieval
35
what does the frontal lobe do
premotor cortex- storage of motor patterns
prefrontal area- concentration, elaboration of though, judgement, inhibition, personality, emotional traits
brocas area language production
motor cortex- voluntary motor activity
36
what symptoms should make you urgently refer a patient on suspicion of a brain tumour
adults- progressive sub acute loss of central neurological function
children- newly abnormal cerebellar or other central neurological function
new onset seizures
headaches
mental changes
cranial nerve palsy
unilateral sensioneural deafness
headaches with symptoms of raised ICP
-vomiting
-drowsiness
-posture relates
-pulse synchronous tinnitus
37
what investigations for suspected brain tumour
CT
MRI
LP
PET
lesion biopsy
EEG
evoked potentials
angiograms
radionucleotide studies
38
is papilloedema a late or early sign of a brain tumour
late
39
what is the commonest brain tumour
mets from other areas
40
what type of cells do gliomas arise from
astrocytes
41
what are grade 1 astrocytomas
benign, slow growing- affects children and young adults
42
what are grade 2 astrocytoma like
not benign
vascular
tend to be in parietal or frontal lobes
present with seizures
43
what are the poor prognostic factors for
over 50
focal deficit
short duration of symptoms
raised ICP
altered consciousness
enhancement on contrast studies
44
what is the treatment for a grade 2 astrocytoma
want to do surgery as can become malignant
or depending on tumour:
serial imaging +/- chemo, radio/ no Tx
45
what are grade 3 astrocytomas like
bad- median survival 2 years
46
what are grade 4 astrocytomas like
really bad- median survival 14 months
47
what is the most common pituitary tumour
astrocytoma
48
what is the treatment for grade 4 astrocytomas
Tx not curative unless present v early with a cyst, surgery- cytoreduction, reduce mass effect, post op radiotherapy
49
can you drive if you have a brain tumour operation
no if seizure risk (all glioblastomas) or if significant visual defect
50
what are the types of chemotherapy
temozolomide, PCV, carmustine wafers
51
what are oligodendrogial
tumour of oligodendrocytes (myelin making cells)
affects frontal lobes, may present with seizures - chem sensitive
52
what does tiptoeing, ataxia and vomiting with headaches in children suggest
BRAIN TUMOUR
53
what are meningiomas like
extra axial
commoner in females
majority asymptomatic
90% benign
54
what are the aggressive types of meningiomas
clear cell, choroid, rhabdoid, papillary, radiation induced
55
what is the Tx for meningiomas
small- leave, pre op embolisation
surgery, radiotherapy
56
what does recurrence of meningiomas depend on
extent of resection and grade
57
what are the types of nerve sheath tumours
schwanomas, neurofibromas, malignant peripheral nerve sheath tumours
58
what are the symptoms of a vestibular schwannoma
hearing loss (unilateral), tinnitus, dysequilibrium
59
what is the treatment of a vestibular schwannoma
'expectant'
hydrocephalus management
radiotherpay
surgery
audiological assessment
60
are vestibular schannomas malignant
1% are
61
what are pineal tumours like
present with parinad syndrome, lots of them hormone secreting, often curable with chemo and radio (germ cell tumours)
62
what do you test in any child with a midline tumour
tumour markers- ALP, HCG, LDH
to see if germ tumour and whether it will be chemo/ radio sensitive
63
what procedure treats hydrocephalus
VP shunt
64
what are the symptoms of a pituitary tumour
bitemporal hemianopia, HA, endocrine abnormality
65
what tests for a pituitary tumour
morning cortisol and prolactin
66