Neuro Flashcards
1
Q
Order of myelination
A
- inferior to superior
- posterior to anterior
- central to peripheral
- sensory then motor
2
Q
last structures to myelinate
A
subcortical white matter (occipital at 12 months, frontal at 18 months)
3
Q
structures that are myelinated at birth
A
- posterior limb of internal capsule
- brainstem
4
Q
order of sinus formation
A
maxillary –> ethmoid –> sphenoid –> Frontal
5
Q
what structures are in the superior orbital fissure
A
CN 3, CN4 ,CN V1, CN6
6
Q
what structures are in the inferior orbital fissure
A
V2
7
Q
Segments of the ICA
A
C1: cervical
C2: petrous:
C3: Lacerum
C4: cavernous
C5: clinoid - aneurysm can compress CN2
C6: Supraclinoid (Ophthalmic) - common site for aneurysm; originats at dural ring
C7: communicating/terminal - aneurysm can compress CN3
8
Q
What structure can get compressed with a subfalcine herniation
A
C
9
Q
What are signs of an uncal herniation
A
aka descending transtentorial
- ipsilateral hemiparesis (Kernohan’s notch phenomenon)
- ipsilateral pupillary dilation and ptosis from CN3 compression
10
Q
Marchiafava Bignami
A
- alcoholics
- edema and T2 bright in corpus callosum (beginning in body, then genu, then splenium); affects central fibers and spares the dorsal and ventral fibers (sandwich sign)
11
Q
disseminated necrotizing leukoencephalopathy
A
- seen in leukemia patients getting radiation and chemo
- severe white matter changes, with ring enhancement
- can be fatal
12
Q
Subcortical Arteriosclerotic Encephalopathy
A
- aka Binswanger disease
- multi-infarct dementia that only involves white matter
- favors white matter of centrum semiovale
- spares subcortical U fibers
- strong association with HTN
- older patients 55+
13
Q
CADASIL
A
Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy
- 40 year old with migraines
- severe white matter disease involving multiple vascular territories in frontal and temporal lobes
- occipital lobes are usually spared
14
Q
Primary brain tumors that can be multifocal
A
- lymphoma
- GBM - can be multicentric or can be multiple from seeding
- gliomatosis cerebri
- Medulloblastoma (from seeding)
- ependymoma (From seeding)
- Oligodendroglioma (From seeding
15
Q
Cortically based tumors
A
PDOG
- pleomorphic Xanthoastrocytoma
- Dysembryoplastic Neuroepithelial tumor (DNET)
- Oligodendrogliomas
- Gangliogliomas
16
Q
Pleomorphic Xanthroastrocytoma (PXA)
A
- ALWAYS supratentorial
- usually involves temporal lobe
- often a cyst with a nodule
- tumor frequently invades leptomeninges
- looks similar to DIG but does not occur in an infant
- occurs at age 10-20
- enhances
17
Q
DNET (Dysembroplastic Neuroepitheilal Tumor)
A
- kid (<20 yrs) with drug-resistant seizures
- temporal lobe
- focal cortical dysplasia seen in 80%
- little surrrounding edema
- Bubbly lesion; high T2 signal
- does NOT enhance
18
Q
Oligodendroglioma
A
- most common in frontal lobe
- calcifies 90%
- expands the cortex
- 1p/19 q deletion - better outcome
- seen in adults (40-50s)
19
Q
Ganglioglioma
A
- low grade; can enhance
- can occur at any age
- usually temporal lobe
- cystic and solid mass with focal calcification
20
Q
Intraventricular tumors - arising from ventricular wall and septum
A
- ependymoma (kids)
- Medulloblastoma (in kids)
- Subependymal giant cell astrocytoma
- subependymoma (in adults)
- central neurocytoma
21
Q
intraventricular tumors - arising from choroid plexus
A
- choroid plexus papilloma
- choroid plexus carcinoma
- xanthogranuloma
22
Q
What syndromes are associated with medulloblastomas?
A
- Basal cell nevus
- Turcot’s syndrome
- Gorlin syndrome
23
Q
Gorlin syndrome
A
- medulloblastoma
- dural calcification
- basal skin cancer after radiation
- odontogenic cysts
24
Q
most common intraventricular mass in an adult 20-40 years old
A
central neurocystoma
25
Cerebellopontine angle masses
schwannoma (75%)
menignioma
epidermoid
26
Infratentorial tumors
- AT/RT
- medulloblastoma
- ependymoma
- JPA
- Hemangioblastoma
- ganglioglioma
- Diffuse Pontine glioma
27
Supratentorial tumors
- Mets
- Astrocytoma
- Gliomatosis cerebri
- oligodendroglioma
- primary CNS lymphoma
28
hemangiopericytoma
soft tissue sarcoma that can mimic an aggressive meningioma because both enhance homogeneously
- will not calcify or cause hyperostosis
- will invade the skull
29
signal of blood on MRI
- hyperacute (<24 hours): T1 iso, T2 bright
- acute (1-3 days): T1 iso, T2 dark
- early subacute (3-7 days): T1 bright, T2 dark)
- late subacute (7-14 days): T1 bright, T2 bright)
- chronic (> 14 days): T1 dark, T2 dark)
30
most sensitive sequence for subarachnoid hemorrhage
FLAIR
31
Iniencephaly
star gazing fetus: upturned face, hypextended C-spine, short neck
- deficit of occipital bones, resulting in an enlarged foramen magnum
32
Joubert syndrome associations
- elongated superior cerebellar peduncles
- small or aplastic vermis
- absence of pyramdial decussation
- strong assocaition with retinal dysplasia
- association with multicystic dysplastic kidney
33
Meckel Gruber syndrome
- occipital encephalocele
- multiple renal cysts
- polydactyly
- strong association with holoprosencephaly
34
Associations with holoprosencephaly
- single midline monster eye
- solitary median maxillary incisor
- pyriform aperture stenosis (From nasal process overgrowth)
35
schizencephaly associations
- optic nerve hypoplasia
- absent septum pellucidum
- epilepsy
36
Chiari 1 malformation association
Klippel Feil syndrome
37
Apert's
brachycephaly + fused fingers
38
Crouzon's
brachycephaly + first arch (maxilla and mandible) hypoplasia
39
Cleidocranial dysostosis
brachycephaly + wormian bones + absent clavicles
40
MELAS
mitochondrial encephalomyopathy, lactic acidosis, and stroke like episodes
on MR spectroscopy: increased lactate; decreased NAA
41
most common leukodystrophy? what does it look like?
Metachromatic
| - diffuse white matter involvement with tigroid apperance
42
High NAA peak
Canavan's disease
43
TE needed to invert the lactate peak
```
intermediate TE (140)
at long TE (280) - lipid and lactate double peak seen
```
44
elevated myoinositol peak
Alzheimer's disease
45
elevated alanine peak
meningiomas
46
elevated glutamine
hepatic encephalopathy
47
high grade tumor: what does the MRS look like?
- elevated choline, lactate, and lipids
| - decreased NAA
48
low grade tumor: what does the MRS look like?
- decreased choline, NAA
| - elevated inositol
49
MRS in radiation necrosis
- decreased choline and NAA
| - increased lactate
50
Gradenigo syndrome
```
complication of Apical petrositis, when Dorello's canal is involved
triad of:
1) otomastoiditis
2) facial pain (trigeminal neuropathy)
3) lateral rectus palsy (CN 6)
```
51
what is the main blood supply to the posterior nose
sphenopalatine artery (terminal internal maxillary artery)
52
most common masticator space "Mass"
odontogenic abscess
53
order of muscle involvement in Grave's orbitopathy
inferior rectus --> Medial rectus --> superior rectus --> lateral rectus --> superior/inferior obliques (IM SLO)
54
ACR recommendations prior to lumbar puncture (regarding anticoagulation)
- stop Plavix 7 days prior
- stop coumadin 4-5 days prior
- stop LMW heparin 24 hours prio
- hold heparin for 2-4 hours and document normal PTT
- ASA and NSAIDS are fine
55
Currarino triad
- sacrococcygeal osseous defect (scimitar sacrum)
- anorectal malformation
- anterior sacral meningocele
56
Foix Alajouanine syndrome
myelopathy associated with a dural VF
