Module 6: Central Nervous, head and neck Flashcards
Incomplete ring enhancement think
demyelination
does stroke restrict
yes
do hypercellular tumours restrict
yes
Herpes encephalitis, does it restrict
yes
Don’t restrcit examples
met
atypical infeciton (toxo)
GBM vs lymphoma
lymphoma enhances homogenously
GBM - heterogenous, aggressive
dawson fingers
Calloso-septal interface
MS
Define for MS
seperation in space and time
MS relationship with which virus
EBV
MS is rarer closer to
the equator
MS trickery
calssic differentials
Vasculitius
Lyme
Vasculitis favours the
basal ganglia
spares the collosal septal interface
Lymes involves more of the
cranial nerves
ADEM stands for
acute disseminated encephalomyelitis
ADEM present in
childhood after vaccination
ADEM appears as
large T2 bright
enhance in ring nodular pattern
though incomplete as demyelination
not invovle the collosal
demyelinating disorder of the spine and optic
NMO (Devic)
neuomyelitis optica
CSF is dark can be
Flair
or
T1
causes of T1 bright basal ganglia
liver failure
hyperlaminetation
high blood sugar
wilsons
does stroke restrict
yes
PRES is what
vascular autoregulation BBB disruption
PRES affects where
bilateral
posterior circulation
watershed areas
PRES history
who gets it
HTN
Pregnancy
chemo
Central Pontine Myeloonitis
rapidly corrected low sodium level
CPM involves which type of cells
oligodendroglial cells
distinguish OM from PRES
DWI
but location more of a giveaway
Wernickes encephalopathy is caused by
thiamine deficiency
Wernickes get enhancement of the
mammillary bodies
T2/Flair signal in bilateral medial thalamus
periaqueductal gray
wernickes ddx
think thalamic insult
artery of percheron infarction
internal cerebral vein thrombosis
high signal crossing the corpus collosum
Marchiafava-Bignami
Marchiafava-Bignami
seen in
drunks
carbon monoxide poisoning
CT hypdensity
T2 bright globus pallidus
why would things in the brain NOT enhance
the BBB
- extra axial
- disrupted the BBB (aggressive infection or high grade tumour)
enahcnement of low vs high grade tumours
high grade DO enhance
- though JPA, grade 1 WHO, this does enhance
- also ganglioglioma
Do low grades enhance
NO
Do high grades enhance
YES
astrocytomas
- two types
diffuse
circumscribed
circumbscribes astrocytoma
JPA - cyst with nodule
Subependymal giant cell
- arise from lateral ventricle
- ax with TS
any intraventricular tumour will enhance or not enhance
will enhance
escapes the BBB
Gliomatosis cerebri
diffuse
involves at least 3 lobes
extensive T2 signal
no mass effect
low grade so doesn’t enhance
tumour that is crossing the midline
GBM
Lymphoma
Tumofactive MS plaque
Radiation
Tumours that restrict diffusion
lyphoma
GBM
medulloblastoma
lymphoma will enhance
uniformaly
choroid plexus xanthogranulomas
benign
7% of people have it
GBM vs Lymphoma
enhancement
GBM - heterogenous rim enhancement
vs
lympohma - homogeous
GBM vs Lymphoma
crossing miudline
both can
restrict
GBM vs Lymphoma
GBM can restrict but lymphoma is classic for restricting
intravascular angiocentric lymphoma
stroke presentation
mutlifocal infarcts
calcium in a brain tumour
most common
Oligodendroglioma
- always calcify
but in real life Astrocytoma so much more common that it could be this
which tumours calcify
Oligodendrogliomas
Ependyomomas
Astrocytoma
GBM
oligodendrogliomas trivia
Ca+2
cortically based
expands the cortex
frontal lobe
has calcium within it
Oligodendrogliomas, prognostic facotr
1P, 19Q deletion, how responsive to radiotherapy
Cortically based tumour
Dysembryolploastic neuroepithelial Tumour (*DNET)
Oligdendrogliomas
gangliogliomas
refactroy seizures
bubbly T2 lesion
DNET
Oligodendroglioma
calcified tumour expands the cortex of frontal lobe
gangliogliomas
cyst with a nodule
differentials for Cyst with a nodule
by location
INfratent
JPA
Haemangioblastomas
Supratent
Pleomorhpic Xanthoastrocytoma
Ganglioglioma
dural tail
PXA
- invades leptomeninges
CP angle tumour
does not go into auditory canal
Meningioma
-0 enhances homogenously
CP angle tumour
goes into the auditory cancal
schwannoma
CP angle tumour
restrict
epidermoid
if CP angle tumour schwanna and bilateral think of
NF-2
low enhancing pituitary lesion
microadenoma
if T2 bright go with RCC
large pituitary
macroadinoma - more than 10mm
Apoplexy will be
T1 bright
sheehans syndrome is
post partum haemorrhage
cant lactate
next step pituitary quesiton
often CT
- for a craniopharyngioma
types of craniopharyngioma
childhood
- calcifies
adult
- pappillary subtype
hypothalamic hamartoma
hamartoma of the tuber cinereum (part of the hypothalamus)
gelastic seizures
precoscious puberty
toothpaste tumour
ependymoma
hard ball tumour
medulloblastoma
age for medulloblastoma
under 10
medulloblastoma are highly cellular and therefore
restrict diffusion
Ependymoma age group
bimodal <5 and > 30
subependymoma
how does it enhance
size
it doesn’t
<2cm
subependymoma age
adult
most paeds tumours
are infratentorial
most paeds are infratentorium except for
Choroid plexus papilloma
lateral trigone
why hydrocephalus in choroid plexus papilloma
secrete CSF
Features in NF1
sphenoid dysplasia
renal vascular stenosis
lateral meningocele
antermedial tibial bowing
NF1 CNS tumour
optic pathway
pilocytic astrocytomas
NF2 cranial features
meningiomas
ependymomas
schwannomas
T2 bright
nodules along ventricles
Subependymal giant cell tumour
renal AML
lung thin walled cysts
Tuberous sclerosis
- subependymal nodules
Cortical tubers
- t2 bright bands
endolymph sac tumour found in
temporal bone
features fo VHL in pancreas
serous cystadenoma
regular cysts
islet cell tumours
features of VHL in CNS
haemangioblastomas in brain and spine
endolymphatic sac tumour
vHL in abdo
phaeo
RCC
renal cysts
corduroy sign, next step
get a mammogram
then thyroid exam
Cowden syndrome
Hamartomas
Breast Ca
Thyroid Ca
Lhermitte-Dulcos
wears corduroy.
enlarged cerebellar hemisphere
SAH along the vertex
truama or vasculopathy
SAH
Basilar
think aneurysm
interpeduncular cistern haemorrhage can be from which aneurysm location
basilar tip
PICA bleeds will go
posterior fossa or intraventricular
MCA aneurysm bleeds go where
sylvian fissure
early s.e of SAH
hydrocephalus due to blood blocking the csf
mid timeframe of SAH
absent vessels
diffuse vasospasms
Vasospasm
- Fischer score
grades risk of vasospasm
1mm of SAH thickness risk of
vasospasm
fleishcherscore of II
why vasospasm with blood
Oxyhemoglobin fownregulates the NO
othe irritants to cuase vasospasm
meningitis - pus
PRES
Reversible cerebral vasospasm syndrome (pregnant thunderclap headache)
Migraine
when does vasospasm happen after SAH
4- 14 days
Late complications of SAH
superficial siderosis
Superfical siderosis appears as
curvilinear low signal on gradient coating the surface of the brain
sensorineurla hearing loss and ataxia and SAH
haemosiderin deposits causes it as a longer term complication of SAH
How does pseudo SAH manifest
brain is dark due to oedema
dura look bright in comparison, mistaken for SAH
look at the sulci, no sulcal density
SAH HU is
60
common locations of hypertensive haemorrhage
basal ganglia (putamen)
pons
cerebellum
T1, white matter is
white
scattered microbleeds on gradient
subcorticol location
lobar bleed with normal BP
dialysis patient
amyloid
how does cytotxic oedema end up hitting the brain
death of sodium potasssium transporter
end up leaking with oedema resultant
normally seen about 3 hours after a stroke
area of restricted diffusion
- its a stroke
but FLAIR is normal.
what could that mean
hyperacute - within first 6 hours
MCA infarcts will normally involve which structure
basal ganglia
(herpes woudn’t)
hypothalamic bilateral infarct
artery of Percharon
wernicker
internal cerebral vein thrombosis
recurrent artery of heubner
branch of proximal ACA
infarct to caudate head
haemorrhagic conversion after strokes
who is at risk
TPA
Anti caog
large territories (1/3MCA distribution)
venous infarcts more likely to bleed
t1 bright
sub acute blood
fat
melanin
proteinacious material
halonised calcium
kids T1 won’t look like an adults until age
1
kids wont’ have the same T2 brain as an adult until
2
types of watershed areas
external and internal
external watershed from
embolic
better prognosis.
internal watershed from
hypoxia
arterial occlusion
deep perforators have few collatorals
i say sickle cell
you say
Moya moya
what is moya moya
proximal ICA / supraclinoid stenosis, chronic so multiple collaterols.
high grade narrowing/occlusion
kid - stroke
adult - bleed
haemosiderin MRI sequence to look for what option
Amyloid
Cavernoma
Blood
Venous malformation in the pons
Capillary telangiectasia
40 year old with migraine
temporal lobe
white matter scarring
normal MRA
not involving the occipital
Cadasil
Cerebral AD arteriopathy subcorticol infarcts and leukencephalopathy
central sulcus seperates which lobes
frontal from parietal
how to find central sulcus
pars bracket sign is immediately behind the central sulcus
inverted omega on the central sulcus represents the
motor hand
Homonculous, the legs are supplied by the
ACA
why does hippocampus look brighter on FLAIR compared to normal cortex
cortex is 6 layers
hippo is 3
what are virchow robins spaces
fluid filled spaces next to perforating vessles.
CSF gets reabsorbed at the
arachnoid granulations
cavum velum interpositum
extension of quadrigeminal plate cistern to foramen of munro
supracellar cisterns look like a
pentagon
sylvian vs ambient cisterns
what are their location
sylvian point anteriorly
ambient point posteriory
MRi appearance of babies
T1 looks like an adult T2
T2 looks like an adult T1
immature myelin has what component compared to mature myelin
more water
therefore is brighter on T2 and darker on T1
last part of the brain to myelinate?
subcortical
which bits of brain are myelinated at birth?
braisntem and posterior limb of the internal capsule
corpus collosum forms in what direction
front to back
cortpus collosum hypoplasia will be absence of which bit ?
splenium
what goes through foramen ovale
V3 Accessory meingeal artery
what goes through Foramen rotundum
V2
what goes through superior orbital fissure
CN3 Cn4 CN V1 CNVI
inferior orbital fissure
what goes through
V2
Orbital and zygomatic branches
foramen spinosum
MMA
jugular foramen
splits into two
what goes through
pars nervosa - J vein, CN 9 and Jacobsons Nerve
para vascularis , CN 10 with auricular branch Arnolds Nerve and 11
hypoglossal canal
CN 12
optic canal
what goes through
CN2 and opthalmic artery
what exists in the cavernous sinus
CN3, 4
CN V1
V2
CN6
3456
why get a lateral rectus palsy
V6 runs next to the carotid artery in cavernous sinus
aneurysm could compress
skull fusion is also called
craniosynostosis
IAC nerve orientation
7up
8 down
nerves anterior
superior and inferior vestibular nerves adjacent
branches of the external carotid
Superior thyroid
Aascending pharyngeal
Lingual
Facial
Occipital
Pposterior auricular
M - maxillary
S - superifical temporal
Common carotid bifurcation at
C3 / C4
C5 portion of internal carotid is called clinoid, an aneurysm here cdan cause
compression of optic nerve and cause blindness
aberrant carotid artery can cause
tinnitus as it courses through the tympanic cavity and joint the horizontal carotid canal
Anastomtic vein of Trolard is where
Top
superficial middle vein and the superior saggital sinus
Anostomatic vein of Labbe
connects the superficial middle vein and the transverse sinus
what are the deep brain veins
basal vein of Rosenthal
Vein of Galen
Inferior petrosal sinus
middle concha is pneumonzied in the nose
Concha bullosa
what is the monro-kellie doctrine
skull is a fixed volume
dynamic between brain, blood and csf
if get leaking CSF what will happen
more blood to accomadate the loss
meningeal engorement.
may get subdural bleeds
Idiopathic intracranial HTN
the csf will decrease to compensate for extra blood pressure.
- slit like ventricles
- pituitary shrinks
- sinuses of blood will appear small
intracranial hypertension in the eys on CT
vertical tortuosity of the optic nerves
flattening of the posterior sclera
what is cytotoxic edema
intracellular swelling
Na/K pump malfunction - stroke/trauma
lose grey white differentiation
What is vasogenic oedema
extracellular due to BBB disruption.
tumour and infection
complicatin of midline shift
copmression of the ACA
what is the first sign o descending trantentorial herniation
effacement of the ipsilateral suprasellar cistern
descending trantentorial herniation
why get pupil dilatation and ptosis
CN3 compression between PCA and superior cerebellar artery
ascending transtentorial erniation will get
smile of the quadrigeminal cistern
spinning top appearance of the midbrain
bad hydrocephalus
involvement of which interface is 98% specific for MS
calloso-septal
Devics MS
Trasnverse myelitis and optic neuritis
PREs is seen in patients with
HTN
Chemo
How does PRES behave on diffusion
does not restrict (ie not a stroke)
Osmotic demyleination syndrome
T2 bright in the central pons
extra pontine presentation involving the basal ganglia, capsule, amygdala, cerebellum
Carbon monoxide poisoning, MRI features
T2 bright globus
CT hypodensity
Alcohol causes brain atrophy, especially the
cerebellar vermis
How will Methanol poisoning show on imaging
optic nerve atrophy
haemorrhagic putaminal and subcortical white matter necrosis
Patient undergoing chem oand radiation may get
dissemintated necrotizing leukoencephalopathy
alzheimers get atrophy of what
hippocampal
temporal horn >3mm
what is crossed cerebellar diaschisis (CCD)
Depressed blood flow and metabolism affecting the cerebellar hemisphere after a contralateral supratentorial insult
Dementia with Lewy body
cingulate island sign
decreased FDG uptake in the lteral ocipital cortex with sparing of the mid posterior cingulate gyrus
Binswanger disease
old people
subcorticol leukencephalopathy
ax with HTN
Huntingtons on FDG PET
low activity in caudate nucleus and putmen
fetus
CMV infection causes what
periventricular tissue necrosis –> calc
can be ax with polymicrogyria
toxoplasmosis seen in
women who clean up cat poo
calc location in toxoplasmosis infeciton
it causes what
basal ganglia
hydrocephalus
MRI features of rubella brian infection
focal high T2 relates to the ischaemic injury and vasculopathy
HSV2 infection in neonatal
thrombus and haemorrhagic infarction
results in encephalomalacia and atrophy
neontal HIV get
brain atrophy in the frontal lobes
AIDS patients get what infection in brain
toxo
AIDS get what fungal infection
cryptococcus
HIV encephalitis affects patietns with a CD4 count
less than 200
MRI findings of HIV encephalitis
T2 /flair increase symmetric signal in deep white matter
spare the subcorticol U fibres
Progressive Multifocal Leukencephalitis caused by
JC virus
PML affects people with a CD4 count less than
50
PML imaging findings
progressive multifocal leukoencephalopathy
hyppodensities with T1 hypodensity
T2 hyperintensity out of proportion to mass effect
love the U fibres
Asymmetry
ependymal enhancement
CMV
cryptococcous
cryptococcomas in the basal ganglia MRI features
T1 dark, T2 bright with ring enhance
Toxo vs lymphoma
toxo is thalium cold
lymphoma thallium hot
Abscess do what with diffusion
restrict
cryptococcus imaging features
dilated perivascular spaces
basilar meningitis
T2 MRI will show what
oedema
IS T2 mri in brain useful
no, as tumor, stroke, MS and infections all have oedema
DWI what restrict
abscess
stroke
hypercellular tumours (lymphoma)
Types of MRI enhancement
Tumour
hetero or homo, if high grade
Types of MRI enhancement
abscess
ring pattern
Types of MRI enhancement
MS
incomplete ring
blank
corticol ribbon
TB meningitis affects where
basal cisterns
otherwise same as regular meningitis
HSV types by kids and adult
HSV 2 in neonates
HSV 1 in adults
what is limbic encephalitis?
paraneoplastic syndrome
small cell lung cancer
looks similar to HSV
Viruses that involve the basal ganglia
Japanese Encephalitis, murray valley fever, west nile
t2 bright basal gangla
CJD - can show on DWI as
cortical gyriform restricted signal
CJD will be seen on multiple imaging over time as
rapid atrophy
neurocysticercosis caused by
eating pig poo
Tinea solium
4 stages of neuocysticercosis
Vesicular - thin walled cysts
Colloidal - hyperdense cyst
granular - cyst shrinks
nodular - small calcified lesion
4 different types of meningitis
bacterial
viral
chronic
non infective
the majortiy of empyema subdurals are a result of
frontal sinusitis
intraventricular extension of asbcess is…
a pre-terminal event
the signs of extra-axial location of brain tumour
CSF cleft
Displaced subarachnoid vessels
Corticol gray matter between mass and white matter
displaced and expanded subarachnoid spaces
Broad dural base/tail
bony reaction
multiple masses in brain differential is between
infection and mets
multiple masses in brain - what to use to discern them
Diffusion
infection will restrict
most common CNS metastasis in a Kid
Neuroblastoma
(bone, dura, orbit)
why do mets commonly sit at the grey white interface
lot of blood flow and abrupt calibre change
Mets can be multiple or
singular.
50% of mets in brain are found solitary
Bleeding mets are
MRCT
Melanoma
RCC
Carcinoid
Thyroid
Mets will have more WHAT compared to primary lesion
oedema
primary tumours that could be multiple
Gliomatosis Cerebri
Multicentric gbm
lymphoma
Tumours ax with
NF1
Optic Gliomas
Astrocytomas
Tumours ax with
NF2
Multiple schwannomas
meningiomas
ependymomas
Tumours ax with
Tuberous sclerosis
Subependymal tubers
IV giant cell astrocytomas
brain Tumours ax with
VHL
haemagnioblastomas
mnemonic for cortically based tumours
P - DOG (round the outside)
PXA
DNET
Oligodendroglioma
Ganglioglioma
seizure,
temporal lobe mass
cystic with solid
focal calcifications
Ganglioglioma
what are the locations for interventricular tumours
Septum pellucidem and ventricular wall
choroid plexus
misc
Septum pellucidem and ventricular wall tumours
Ependymoma
Medulloblastoma
Subependymal giant cell astrocytoma
Central neurocytoma
tumours o the choroid plexus
Papilloma
Carcinoma
Xanthogranuloma
Misc ventricular tumour
Mets
Meningioma
Colloid cyst
tooth paste tumour
ependyomoma
age of ependymoma
less than 6 and >30
age of medullblastoma
less than 10
do medulloblastoma restrict
yes
tightly packed cells
what are the mets called for medulloblastoma in the spine
drop mets
posterior fossa neoplasm in a child, next step
image the whole spine
where do medulloblastoma and ependyomoma orginate within the ventricles
medulloblastoma - vermis, 4th vent roof
ependyomoma - floor of the 4th ventrcile
adult intraventricular tumours are
subependyomoma
Central neurocytoma
Subependyoma - imaging features
don’t enahce.
T2 bright as are most tumours.
Swiss chesse appearance of Intraventricular mass in an adult
central neurocytoma
Choroid plexus origin tumours
Papilloma
Carcinoma
Xanthogranuloma
Choroid plexus papilloma/carcinoma
what expesion to a rule is this cancer
exists in the supratentorium in KIDS
choroid plexus papilloma in kids
doesn’t exists.
only the carcinoma type
found in the lateral ventricle/trigone
risk of having a colloid cyst
sudden death from rapid onset hydrocephalus
dense
what nuclear medicine test is there for meningiomas
octreotide and Tc-MDP on nuclear medicine tests
dermoid cysts found where
midline
30s
dermoid cysts imaging features
contain lipoid materal and are usually hypodense on CT and very bright on T1
ax with NF2
Epidermoid vs dermoid
epidermoid behave like CSF
dermoid behave like fat
arachnoid cysts - restriciton pattern
do not restrict
full list of infratetnorial malignancies
Atypical teratoma
JPA
Diffuse brain stem glioma
gnaglioglioma
medulloblastoma
ependymoma
haemangioblastoma
diffuse brain cell glioma imaging appearance
T2 bright, subtle to no enhancement
4th ventricle will be flattened
most common supratentorial mass
mets
midline sacrum tumour
chordoma
tumours of the Dura
Meningioma
Hemangiopericytoma
Mets (breast)
pituitary secrets what
FLAT PEG
FSH
LSH
ADH
TSH
prolactin
endorphins
gsh
sella / parasella in adults tuour
Adenoma
Apoplexy
Rathke cleft cyst
epidermoid
craniopharyngioma
sella / parasella in kids tumours
Craniopharyngioma
Hypothalamic hamartoma
dorsal parinaud syndromes are what kind
vertical gaze palsy
3 pineal tumours
Germinoma
Pineoblastoma
Pineocytoma
germinoma may secrete what causing….
hCG causing precocious puberty
germinoma has what make up
fat and calcifiations
pineoblastoma is what
invasive
pineoblastoma is ax with
retinoblastoma
NF2 cranial lesions
MSME
Multiple Schwannomas
Meningiomas
Ependymomas
Cowdens has what issues
hamartomas everywhere
if the brain scrapes against the skull base in a collision can cause
parenchymal contusion
anterior temporal lobes
inferior frontal lobes
diffuse axonal injury - locations
posterior corpus callosum
GM - WM junction in frontal and temporal
DAI - on MRI
multiple small T2 bright foci
how many le fort fractures are there?
3
Describe LeFOrt 1 - 3
1 - maxilla
2 - pyarmaidal
3. face falls off
most common facial fracture
nasal bone
with temporal bone fractures you should describe what
whether there is otic involvement.
Blood on CT has what timeframe density changes
hyperacute - <1 hr –> hypodense
acute up to 3 days –> hyperdense
subacute 4days to 3 weeks –> progressively less dense
Chronic is more than 3 weeks - hypodense
swirl sign bleed
badness
active bleeding
MRI blood signal through time
swirl graph
most sensitive sequence on mri for SAH
FLAIR
benign non-aneurysm perimesencephalic haemorrhage
NOT ax with aneurysm but with venous bleed.
Classic appearance of around the midbrain and pons with extension into the lateral sylvian cisterns
superficial siderosis from repeated SAH can cause what
hearing loss and ataxia
hypertensive haemorrhage location
basal ganglia
duret haemorrhage
herniation causes mesial temporal lobe to herniate down through tentorium.
haemorrhage of the medulla and pons
Petrous bone, fracture types
Longitudinal and transverse
Longitudinal fracture through the petrous bone
what kind of hearing loss
conductive hearing loss as it hits the ossicles
Transverse petrous fracture can damage which nerve
facial nerve
violate the otic capsule
what can happen
increwased risk of the following
csf leak
facial nerve damage
increase sensorineural hearing loss
What is FLAIR
inversion sequence to null CSF
fake out SAH on FLAIR
metal stops the inversion.
- so can still see bright CSF
inhaled oxygen therapy
infection
propofol
airless exapnded sinus
mucocele
MRI features of mucocele
T1 bright
maybe peripheral enhancement
pulsatile exmopthalmos
look to the cavernous sinus
prominent superior opthalmic vein
carotid cavernous fistula
indirect carotid cavernous fistula
between cavernous sinus and meningeal branch of the External carotid artery
what fracture do all le fort have in common
Pterygoid processes
inferior orbit fracture
what Le Fort
2
Lateral orbital wall and zyg arch
le fort type?
3
circumferential calcification around the ventricles
CMV
basal ganglia calcifications
hydrocephalus
infection
Toxo
asymmetric, peripheral
involves the U fibres
T1 is normal
JC virus
(PML)
Symmetric and central lesionson on MRI
HIV encephalitis
mucoid gelatinus cysts
will be presented as a meningitis with affecting the base of the brain
cryptococcus
ring enhancing lesion with LOADS of edema
doesn’t restrict
Toxo
toxo v lymphoma
thallium cold on toxo
lymphoma hot
if there is lots of Basilar tissue enhancement think
Sarcoid
TB meningitis
cortical gyriform restricted diffusion
CJD
nec fascitis in face
Ludwigs angina
start as a tooth infection
odontogenic abscess more common from extracted or intact tooth
extracted
mylohyoid line seperates what
infection from back teeth goes to submandibular space
if anterior to the 2/3 molar will be sublingual space
grandenigo syndrome
lateral rectus palso
ottomastoiditis
face pain
Petrous apex infection case
watershed infarcts in a kid
moya moya
sickle cell
what is the insular ribbon sign
loss of normal high density insular cortex from cytotoxic oedmea
post stroke mass effect will peak at
day 3-5
what is fogging
appearance post stroke of brain looking fnormal
2-3 weeks
in context of stroke
restricted diffusion without bright signal on FLAIR consider
subacute <6hrs stroke
what things restrict?
stroke
abscess
CJD
Herpes
Hypercellular tumours (lymphoma)
MS lesions
oxyhaemoglobin
Post ictal states
Enhancement post stroke
rule of 3s
starts day 3
peaks 3 weeks
gone 3 months
predictors of patients getting haemorrhagic transformation from stroke when on TPA
Multiple strokes
prox MCA occluded
1/3 territory of MCA territory
more than 6 hours since onset to recanalization
absent collateral flow
venous infarction associations in kids
babies - dehydration
in kids - mastoiditis
what can happen after a chronic venous thrombosis
get a dural AVF
or high CSF pressures if impaired drainage
berry aneurysms are seen at
bifurcation points
Fusiform aneurysm is ax with
PAN
Connective tissue disease
Syphilis
Seen in posterior circulation
pseudo aneurysm how to spot
odd location
outpouching
focal haematoma next to the vessel
pedicle aneurysm is an aneurysm ax with a
AVM
mycotic aneurysm found in X
History will include what
distal MCAs
endocarditis, meningitis, thrombophlebitis
what puts a high flow AVM at a higherbleeding risk
small size
single draining vein
intranidal aneurysm
location
- basal ganglia, thalamic/periventricular locations
dural AVF involving the sigmoid sinus can cuase
pulsatile tinnitus
cavernous malformaiton
low flow lesions with a dilated capillary bed
WITHOUT intervening normal brain tissue
capillery telengiectasia
low flow
DOES have intervening normal brian tusse
vascular dissection from blunt vs pentrating truama
penetrating think carotids
blunt look at vertebrals
how to categorise vasculitis in brain
primary
secondary
Systemic vasculitis disease hitting the brain
CNS vasculitis from systemic disease
Primary causes of brain vasculitis
Primary Angiitis of the CNS
(P A C N S )
Seocndary causes of brain vasculitis
Meningitis
Septic embolus
Sarcoid
Systemic vasculitis disease hitting the brain
PAN
Temporal arteritis
Wegeners
Takayasy’s
CNS vasculitis from systemic disease
Cocains use
RA
SLE
Lyme’s
segmental areas of vessel narrowing with beaded appearance
vasculitis
colpocephaly is what
asymmetric dilation of the occipital horns
when seing colpocephaly think
corpus callosum agenesis
pericallosal lipoma
intracranial lipoma is most often found in
interhemispheric fissure
probst bundles are what
dense packed white matter tracts, would cross the CC if present, if Corpus Callosum not present they run parallel and make the ventricles appear far from each other
anencephaly is what
neural tube fails to close on cranial end.
reduced or absent cerebrum/cerebellum.
hind brain present
MR SPECT
NAA corresponds to what
neuronal integrity
what is the exception for high NAA being normal
will be super high in Canavans
MR SPECT
Choline is high with what
cell turnover
tumour, infarct or inflammation
with what TE will you see a double Lcatate lipid peak ?
Long TE (280)
in which normal circumstance is lactate seen in the head
hours after birth
what is raised in alzheimers and low grade gliomas
MR SPECT
Myoinositol
Alanine elevation is specific to which tumour
MR SPECT
meningiomas
mengiomas have a raised what and absent what on
MR SPECT
have alanine elevation
but absent NAA
MR SPECT
Glutamine elevation is sign of what
hepatic encephalopathy
High grade tumour
MR SPECT
choline, NAA, lactate and lipids
choline up
NAA down
lactate and lipids are up
LOW grade tumour
MR SPECT
choline, NAA, lactate and lipids
choline down,
NAA down,
Inositol UP
Paeds heads
How to discern between a BESSI and a subdural
Cortical veins
Subdural bleed, bleeds displaced away from the inner table
BESSI: Cortical veins are adjacent to the inner table
paeds heads
extra axial fluid spaces are considered enlarged if greater than
5mm
BESSI stands for
benign enlargement of the subdural spaces in infancy
choanal atresia might cause what situation to arise for the patient?
resp distress whilst feeding
Unable to pass an NG tube
what associations are there for choanal atrsia
CHARGE
Crouzons
DiGeorge
Treacher COlins
Getal Alcohol syndrome
what is MELAS (paeds condition)
Mitochondrial disorder with lactic acidosis and stroke like episodes
