Neuroradiology Flashcards
1
Q
Foramen ovale
A
CN V3, accessory meningeal artery
2
Q
Foramen rotundum
A
CN V2
remember “R2V2”
3
Q
Superior orbital fissure
A
CN 3, 4, V1, 6
4
Q
Interior orbital fissure
A
CN V2
5
Q
Foramen spinosum
A
Middle meningeal artery
6
Q
Jugular foramen
A
Pars nervosa: CN 9
Pars vascularis: CN 10, 11
7
Q
Hypoglossal canal
A
CN 12
8
Q
Optic canal
A
CN 2 and ophthalmic artery
9
Q
Branches of external carotid artery
A
“Some Administrators Like Fucking Over Poor Medical Students”
Superior thyroid Ascending pharyngeal Lingual Facial Occipital Posterior Auricular Maxillary Superficial temporal
10
Q
Signs of extraaxial location of a mass
A
CSF cleft
Displaced subarachnoid vessels
Cortical gray matter between the mass and white matter
Displaced and expanded subarachnoid spaces
Broad dural base/tail
Bony reaction
11
Q
Order of questions to narrow differentials for brain tumors?
A
Is it a tumor? (Vs plaque, inf, etc);
Single or multiple masses?;
If single, adult or kid?;
Location.
12
Q
Brain Tumor differentials by location: cortical (4)
A
P-DOG
Pleomorphic xanthoastrocytoma,
Dysembryoplastic Neuroepithelial Tumor,
Oligodendroglioma,
Ganglioglioma
13
Q
Brain Tumor by location: 3 “interventricular” regions from which tumors can arise
A
Ventricular wall,
Septum pellucidum,
Choroid plexus
14
Q
Brain Tumor differentials by location: Interventricular–ventricular wall/septum pellucidum (5)
A
Ependymoma, Medulloblastoma, Subependymal Giant Cell Astrocytoma (SEGA), Subependymoma, Central Neurocytoma.
15
Q
Brain Tumor differentials by location: Interventricular–choroid plexus (3)
A
Choroid plexus Papilloma,
Choroid plexus Carcinoma,
Xanthogranuloma.
16
Q
Brain Tumor differentials by location: interventricular–other miscellaneous (3)
A
Mets,
Colloid cyst,
Meningioma.
17
Q
Brain Tumor differentials by location: Cerebellar Pontine Angle (6)
A
Vestibular Schwannoma, Meningioma, Epidermoid, Dermoid Cyst, IAC Lipoma, Arachnoid Cyst.
18
Q
Brain Tumor differentials by location: Infratentorial (7)
A
Atypical Teratoma/Rhabdoid, Juvenile Pilocytic Astrocytoma, Diffuse Brain Stem Glioma, Ganglioglioma, Medulloblastoma, Ependymoma, Hemangioblastoma.
19
Q
Brain Tumor differentials by location: Supratentorial (8)
A
Mets, Astrocytoma, Gliomatosis Cerebri, Oligodendroglioma, Primary CNS Lymphoma, Pleomorphic Xanthoastrocytoma (PXA), DNET, Desmoplastic Infantile Ganglioglioma/Astrocytoma (DIG).
20
Q
Brain Tumor differentials by location: Skull base (2)
A
Chordoma,
Chondrosarcoma.
21
Q
Brain Tumor differentials by location: Dura (3)
A
Mets,
Meningioma,
Hemangiopericytoma.
22
Q
Brain Tumor differentials by location: Sella/Parasella (ADULTS) (5)
A
Pituitary adenoma, Pituitary Apoplexy, Rathke Cleft Cyst, Epidermoid, Craniopharyngioma.
23
Q
Brain Tumor differentials by location: Sella/Parasella (PEDS) (2)
A
Craniopharyngioma,
Hypothalamic Hamartoma.
24
Q
Brain Tumor differentials by location: Pineal Region (4)
A
Germinoma,
Pineoblastoma,
Pineocytoma,
Pineal Cyst.
25
Differentials for multiple brain masses.
Mets, infection, or multifocal primary brain tumors (always think mets before multifocal primary!)
26
How do you differentiate between mets and infection when looking at multiple brain masses?
Diffusion. Infection will restrict.
27
Most common CNS met in kid
Neuroblastoma
| Bones, Dura, Orbit---not brain!!
28
Most common location for brain mets?
Supratentorial at the Grey-White Junction (a lot of blood flow and abrupt vessel caliber change, so also see hematogenous infection/ septic emboli go there first too).
29
Most common morphology for brain mets?
Round or spherical
30
True or False: brain mets usually present as multiple masses.
False. 50% of brain mets are solitary. In adult, solitary mass more likely to be met than primary CNS neoplasm.
31
Differentials for bleeding brain mets (4)
MRCT
Melanoma,
Renal,
Carcinoid/choriocarcinoma,
Thyroid.
32
# Choose one:
Usually mets have (less/more) surrounding edema than primary neoplasms of similar size.
Mets have More
33
You're shown a solitary intra-axial mass in an adult. What is the best next step?
Go looking for the primary. Most common intra-axial mass in an adult (solitary or multiple) is a met. Look for common things (lung, breast, colon, etc).
34
Primary brain tumors that like to be multifocal (3)
Lymphoma,
Multicentric GBM,
Gliomatosis Cerebri.
35
Primary brain tumors that are often multifocal from seeding (4)
Medulloblastoma,
Ependymoma,
GBM,
Oligodendroglioma.
36
Choose one:
| Tumors with syndromes are more likely to be (solitary/multifocal).
Multifocal
37
Syndromes that often produce multifocal brain tumors (4)
NF1,
NF 2 "MSME",
Tuberous Sclerosis,
VHL.
38
Brain tumors associated with NF1
Optic Gliomas,
| Astrocytomas
39
Brain tumors associated with NF2 "MSME"
Multiple Schwannoma,
Meningiomas,
Ependymomas,
40
Brain tumors associated with Tuberous Sclerosis
Subependymal Tubers
| IV Giant Cell Astrocytoma
41
Brain tumors associated with VHL
Hemangioblastomas
42
Brain tumor mimics (3)
Abscess,
Infarct,
Big MS plaque
43
Top differential if shown an incomplete ring with a brain mass
Giant MS Plaque
44
Top differentials (3) if shown brain mass with diffusion. What should you use to differentiate?
Lymphoma, stroke, Abscess
Differentiate: use enhancement (lymphoma enhances homogeneously.)
45
Signs of extra-axial location of brain masses:
CSF Cleft,
Displaced Subarachnoid Vessels,
Cortical Gray matter between mass and white matter,
Displaced and expanded subarachnoid spaces,
Broad dural base/tail,
Bony Reaction.
46
What keeps things from enhancing? Why do some things enhance?
Blood-brain barrier
Things that DO enhance are either outside the BBB (extra-axial, like meningioma) or melted the BBB (like high-grade tumors and infections).
47
What are the 2 exceptions to the general rule that low-grade tumors do not enhance?
Ganglioglioma,
Pilocytic Astrocytoma.
Both enhance despite being low-grade tumors.
48
Choose one: Most intra-axial tumors are located in the (gray/white) matter.
White
49
# Choose: Cortical tumors/cortical mets have (very little/moderate/tons of) edema.
Why is this important?
Cortical tumors have very little edema.
So small cortical mets can be occult without IV contrast!
50
Oligodendroglioma: most common location
Frontal lobe
51
Oligodendroglioma: radiographic findings
Frontal lobe,
"Expands the cortex"--buzzword (cortical infiltration and marked thickening),
Calcified 90% of time,
Can enhance
52
Calcified brain mass (top 2 differentials and likelihood of answer being each.)
Oligodendroglioma--calcifies 90% of the time (but not very common)
Astrocytoma--calcifies 20% of time (but more common IRL)
On exam: probably oligodendroglioma.
IRL: more likely still astrocytoma
53
"1p/19q deletion." Which mass?
Oligodendroglioma
54
Choose: 1p/19q deletion, as pertains to Oligodendroglioma, has (better/worse) outcome.
Better
55
Oligodendroglioma: age
Adult (40s-50s)
56
Ganglioglioma: age
Any age
57
Ganglioglioma: radiographic findings
Can enhance,
NOT bubbly,
Can look like anything (any age, anywhere, look like anything.)
Classic M/c scenario: 13 yr old w/seizures, temporal lobe mass that is cystic and solid w/focal calcifications +/- overlying bony remodeling.
58
Dysembryoplastic Neuroepithelial Tumor (DNET): age
Peds <20 years
59
Dysembryoplastic Neuroepithelial Tumor (DNET): radiographic features
```
Does NOT enhance,
High T2 Signal "Bubbly lesion",
Temporal lobe (100% on exam, 60% IRL),
Focal cortical Dysplasia (80%),
Hypodense on CT,
MRI: little to no edema.
```
60
Dysembryoplastic Neuroepithelial Tumor (DNET): preferred location
Temporal lobe (100% on exam, 60% IRL)
61
Dysembryoplastic Neuroepithelial Tumor (DNET): classic history
Kid with drug-resistant seizures
62
Pleomorphic Xanthoastrocytoma (PXA): age
Peds (10-20 years)--not infant!
63
Pleomorphic Xanthoastrocytoma (PXA): radiographic features
```
Will enhance,
Supratentorial (always),
Temporal lobe (usually),
Dural Tail (??--pg 155, not sure what about it.),
Cyst with nodule (frequent appearance)
No peritumor T2 signal,
Invades leptomeninges,
Looks just like Desmoplastic Infantile Ganglioglioma BUT not in an infant!
```
64
Cortical based brain tumors: of the differentials (PDOG), which can/will/don't enhance?
P-will
D-does NOT
O-can
G-can
65
Cortical based brain tumors: which "expands the cortex"
Oligodendroglioma
66
Cortical based brain tumors: which is calcification common
Oligodendroglioma
67
Cortical based brain tumors: which has high signal "bubbly lesion"
DNET
68
Cortical based brain tumors: which is often cyst with a nodule?
PXA
69
Interventricular tumors, ventricular wall and septum pellucidum--general age group for each differential (ependymoma, medulloblastoma, SEGA, Subependymoma, central neurocytoma)
```
E-PEDS
M-PEDS,
SEGA-PEDS,
Sub-adults!!!
Central-young adult
```
70
Interventricular tumors, choroid plexus--general age group for each differential (choroid plexus papilloma, choroid plexus carcinoma, xanthogranuloma)
CPP-PEDS (trigone) and Adults (4th ventricle),
CPC-PEDS,
X-Adults
71
Ependymoma: age
Peds (peak 6 years, tiny peak at 30 years, but for purpose of exam, think of as peds)
72
Ependymoma: 2 locations and % of cases for each
```
4th ventricle (70%),
Parenchyma Supratentorial (30%)
```
73
Ependymoma: radiographic features
Ventricular type:
* From FLOOR of 4th ventricle.
* "Toothpaste tumor"-squeeze out of 4th ventricle through foramen of Luschka and Magendie into basal cisterns.
Supratentorial: big (>4cm) at presentation
Both types:
* Enhance HETEROGENEOUSLY.
* Calcify 50% (more than medulloblastoma)
74
Medulloblastoma: age
Peds--Most before age 10 (another peak at 20-40, but ignore for exam)
75
Medulloblastoma: radiographic features
* from vermis/ROOF of 4th ventricle.
* can project down into 4th ventricle, but do NOT extend into basal cisterns.
* enhance homogenously (more than ependymoma, anyway).
* calcify less (20%)
* "ZUCKERGUSS"--German, "sugar icing," linear "icing-like" enhancements of the brain surface
* hypercellular, may restrict
76
Medulloblastoma: location
Vermis/ROOF of 4th ventricle .
| Can project down into 4th ventricle, but do NOT usually extend into basal cisterns.
77
Medulloblastoma vs Epedymoma, prevalence
Medulloblastoma much more common than ependymoma (chief differential)
78
Medulloblastoma: metastasis prevalence and pathway
Love to met via CSF pathways. They "drop met."
79
Zuckerguss! Which tumor. What does it mean.
Medulloblastoma.
Linear "icing-like" enhancements of brain surface post contrast imaging.
80
Medulloblastoma: syndrome associations (3)
Basal Cell Nevus Syndrome,
Turcots Syndrome,
Gorlin Syndrome.
81
Medulloblastoma with thick dural calcs. What Syndrome?
Gorlin Syndrome
82
Gorlin Syndrome
* medulloblastoma and thick dural calcs.
* basal cell skin cancer after radiation.
* odontogenic cysts.
83
Child with posterior fossa neoplasm. Next step?
Preoperative imaging of entire spinal axis should be done in any child w/posterior fossa neoplasm, especially if ependymoma or medulloblastoma suspected. Evidence of tumor spread is predictor of outcome.
84
Medulloblastoma vs ependymoma: enhancing pattern
M: more homogenous than ependymoma
E: heterogeneous
85
Subependymal Giant Cell Astrocytoma (SEGA): classic history
Going to be shown in the setting of TS. Likely show renal AMLs or tell you kid has seizures. Syndromic, kids (avg age 11).
86
Subependymal Giant Cell Astrocytoma (SEGA): age
Peds (avg age 11)
87
Subependymal Giant Cell Astrocytoma (SEGA): radiographic features
From lateral wall of the ventricle, near foramen of Monro.
Often causes hydrocephalus.
Enhances homogeneously.
88
Subependymal Giant Cell Astrocytoma (SEGA): typical location
Lateral wall of ventricle, near foramen of Monro.
89
SEGA vs Subependymal Nodule (SEN): 3 biggest differences
1. Growth habit--SEGA will grow, SEN stays stable.
2. Location--SEGA found in lateral ventricle near foramen of Monro. SEN can be anywhere along ventricle.
3. Prevalence--SEN much more common.
(Both can calcify)
90
Enhancing, partially calcified lesion at the foramen of Monro, bigger than 5mm. SEGA or SEN?
SEGA.
91
Which 2 ventricular wall/septum pellucidum tumors are in adults?
Subependymoma,
| Central Neurocytoma
92
Subependymoma: age
Adults
93
Subependymoma: location
Usually at foramen of Monro and the 4th ventricle.
94
Subependymoma: radiographic findings
```
Well-circumscribed,
usually at foramen of Monro and 4th ventricle,
can cause hydrocephalus,
Typically do NOT enhance,
T2 bright (like most tumors).
```
95
Central Neurocytoma: age
Adults (20-40)
96
Most common interventricular mass in adults aged 20-40.
Central Neurocytoma
97
Central Neurocytoma: radiographic features
"Swiss cheese" appearance of numerous cystic spaces on T2.
| Calcify a lot! (Almost like oligodendrogliomas.
