Neuroradiology Flashcards
(218 cards)
1
Q
Enlarged perivascular (virchow robin) spaces?
A
- Cryptococcus (gelatinous pseudocyts, do not enhance) - Mucopolysaccharidoses (hunters, Hurlers) - Atrophy VR don’t contain CSF
2
Q
Myelination pattern?
A
Progression: inferior to superior, posterior to anterior, central to peripheral Subcortical white matter is last to myelinate Brainstem and posterior limb of internal capsule are myelinated at 36 weeks
3
Q
Corpus Callosum Development?
A
Front to back (but the rostrum is last)
4
Q
Immature Myelin Appearance?
A
Higher water content- brighter on T2 and darker on T1 Mature myelin- bright on T1 and T2 dark T1 (1 yo) changes proceed T2 changes (2yo)
5
Q
Paranasal sinus formation?
A
Maxillary -> Ethmoid -> Sphenoid ->Frontal
6
Q
Foramen Ovale
A
CN V3, accessory meningeal artery
7
Q
Foramen Rotundum
A
CNV2 (R2V2)
8
Q
Superior Orbital Fissure
A
CN 3,4, V1, and CN 6
9
Q
Inferior orbital fissure
A
CN V2
10
Q
Foramen Spinosum
A
Middle meningeal artery (spine contains meninges)
11
Q
Jugular foramen
A
Jugular vein, CN 9, CN 10, CN 11
12
Q
Hypoglossal canal
A
CN12
13
Q
Optic canal
A
CN 2 and opthalmic artery
14
Q
What runs in the cavernous sinus
A
CN 3, 4, V1, V2, CN 6 (CN 2 and CN V3- do not run in)
15
Q
What nerve is adjacent to the carotid artery in the cavernous sinus and is not within the wall?
A
CN6
16
Q
Branches of external carotid?
A
Some administrators like fucking over poor medical students Superior thyroid Ascending pharyngeal Lingual Facial Occipital Posterior Auricular Maxillary Superficial temporal
17
Q
Internal Carotid Artery Branches?
A
C2- petrous C3 - Lacerum C4- Cavernous (site of CC fistulas) C5- Clinoid ( aneurysm can compress the optic nerve at this level) C6-Ophthalmic (origin at the dural ring- intrdural) C7- Communicating terminal (aneurysm can cause CN III palsy)
18
Q
Fetal PCA?
A
PCOM is as large or bigger then the P1 segment PCOM is superior and lateral to CN 3 (as opposed to superior and medial in normal anatomy)
19
Q
Deep Cerebral Veins
A
Basal Vein of Rosenthal Vein of Galen Inferior Petrosal Sinus
20
Q
Superficial Cerebral Veins
A
Vein of Trolard (drains into superior sagittal sinus) Vein of Labbe (drains into the transverse sinus) Superficial Middle Cerebral Veins Superior Cerebral Veins
21
Q
CN III Palsy
A
Terminal Aneurysm Aneurysm of the PComm Artery
22
Q
CN 6 palsy
A
Increased intracranial pressure
23
Q
Intacranial hypotension
A
Sagging of midbrain meningeal enhancement distension of dural venous sinuses
24
Q
Intracranial Hypertension
A
Empty Sella Optic Hydrops Papilledema
25
Vasogenic Edema
Extracellular
26
Cytotoxic edema
Intracellular Na/K pump
27
Hydrocephalus
Obstructive: Non-communicating- involves the ventricular system Communicating-Involves the villi/arachnodi granulations Non-obstructive: Increased production of CSF- choroid plexus papilloma
28
Transtentorial Herniation
Effaces ipsilateral suprasellar cistern first Duret hemorrhage from basilar artery perforators
29
Multiple Sclerosis
- Relapsing and remitting is most common type - Acute plaques should restrict diffusion - Tumefactive- incomplete ring enhancement Marburg- childhood variant, fulminant, rapid demise
30
ADEM
Post-viral/vaccination T2 bright lesions, which enhance in a nodular/ring like fashion Typically don't involve the collosal septal interface
31
Hurst Disease/ Acute Hemorrhagic Leukoencephalitis?
Fulminant from of ADEM, hemorrhage on seen on autopsy
32
Wenick'e Encephlopathy
Enhancing mammillary bodies Edema in the medial thalami and periaqueductal gray matter
33
Carbon monoxide
T2 bright globus palladi
34
Marchiafava-Bigmani
Demylination and Necrosis of the CC- T2 hyperintense signal in the corpus callosum, which starts in the central CC Associated with alcoholism and chronic nutritional deficiencies
35
What is preserved on FDG-PET in dementia?
Motor strip
36
Mimics of vascular dementia?
Lyme disease, HIV, Vasculitis
37
First sign of alzheimer's?
Hippocampal atrophy (temporal atrophy \> 3 mm is suggestive)
38
Crossed Cerebellar Diaschisis
contralateral cerebellum has decreased uptake
39
Binswangers
Small vessel vascular dementia spares subcortical U-fibers
40
TORCH- CMV
Most Common TORCH infection - Periventricular calcifications - Highest association with polymicrogyria
41
TORCH- Toxoplasmosis
Associated with hydrocephalus Basal ganglia calcifications
42
TORCH- HSV
HSV-type 2 Thrombus and hemorrhagic infarctions
43
HIV- Intrauterine
Atrophy of the frontal lobes
44
PML
JC virus Involves the subcortical U fibers CD4 count typically less than 50 T2 lesions out of proportion to mass effect
45
Toxoplasmosis
Most common opportunistic infection in HIV T2 bright, ring enhancing lesion, lots of edema, NO RESTRICTION Cold on thallium (lymphoma is hot on thallium)
46
Hydrocephalus and nodular enhancement of the basilar meninges?
TB (sarcoid generally does not cause hydrocephalus)
47
HSV infection- Adults
HSV 1 First sign is restricted diffusion May have hemorrhage
48
Limbic Encephalitis
Paraneoplastic syndrome (ex: small cell carcinoma of the lung) No enhancement
49
CJD
Diffusion restriction-cortical ribboning, hockey stick sign (medial thalamus)
50
Stages of Neurocysticercosis
1. Vesicular- thin walled cyst, no edema 2. Colloid- Hyperdense cyst with edema 3. Granular- cyst shrinks, wall thickens (less edema) 4. Nodular- calcified lesion, no edema
51
Cortically Based Tumors?
Dysembryoplastic Neuroepithelial Tumor (DNET) Oligodendroglioma Ganglioglioma
52
NF1
Optic gliomas/Astrocytomas Plexiform neurofibromas Iris Hamartomas
53
NF2
Multiple schwannomas Meningiomas Ependymomas
54
Tuberous Sclerosis Tumors
Subependymal tubors Giant Cell astrocytomas
55
VHL
hemangioblastomas (cerebellar) Others: Pheochromocytomas Retinal angiomas Choriod plexus papilloma Endolymphatic sac tumor Pancreatic cyst, islet cell tumor, adenocarcinoma RCC- clear cell Renal AML, cysts Liver cysts Cysts of the epididymis
56
What low grade tumors can enhance?
JPA, gangliogliomas
57
Restricting lesion in the CP angle?
Epidermoid
58
Calcified cortically based mass?
Oligodendroglioma 1p/19q deletion have a better prognosis
59
Hemorrhagic Mets?
RCC Thyroid Melanoma Choriocarcinoma
60
What is associated with GBM?
Turcot Syndrome- medulloblastoma, intestinal polyposis
61
Hemangioblastoma?
Associated with VHL Can cause polycythemia (increased epo levels) Cyst with enhancing mural nodule, can have prominent flow voids
62
Benign choroid plexus mass that restricts diffusion?
xanthogranuloma Do not touch lesion
63
Most common type of functional pituitary adenoma?
prolactinoma
64
Pituitary apoplexy is assocaited with?
Bromocriptine use Sheehan Syndrome- post-partum necrosis
65
Craniopharyngioma?
Calcifications Can have papillary- Solid and capsule (adult) or Adamantinomatous type, cysts which can have protein and hemorrhage (peds)
66
Meningiomas can be hot on what nuclear medicine studies?
Tc-MDP octreotide
67
Which CPA mass invades to internal auditory canal?
Schwannoma- widen porus acousticus Meningiomas typically don't widen IAC
68
What differentiates ana arachnoid cyst from epidermoid?
Epidermoid restricts diffusion and are mildly bright on FLAIR, both lesions follow CSF signal
69
Most common dural metastases?
Breast Cancer
70
Hemangiopericytoma
-Aggressive sarcoma that invades skull, can mimic an aggressive meningioma -Don't Calcify
71
Rapidly increasing head circumference in child
Desmoplastic infantile ganglioglioma/ Astrocytoma Typically supratentorial, cystic masses
72
Most common location of Choroid Plexus Papilloma?
Adults- 4th ventricle Kids- Lateral ventricle (usually trigone)
73
Where does neuroblastoma like to involve?
Calvarium Dura Postero-lateral aspect of orbits
74
Dysembryoplastic Neuroepithelial Tumor Characteristic?
Temporal Lobe T2 Bubbly appearance Frequently presents as drug resistant seizures
75
Pleomorphic Xanthroastrocytoma
Temporal lobe involvement Cyst with nodule
76
What lesion is in the tuber cinereum and assocaited with gelastic seizures?
Hypothalamic Hamartoma (most common presenting sign is actually precocious puberty)
77
Medulloblastoma?
Typically arise from vermis and project into 4th ventricle Restrict diffusion, enhance homogenously Drop mets are common Associated with basal nevus syndrome and turcots
78
What is gorlin syndrome?
Medulloblastoma + dural calcifications + basal cell skin cancers + odontogenic cysts
79
Pineal mass containing fat and calcifications?
Germinoma- engulf the pineal gland (pineocytoma and pineoblastoma expand the pineal gland) Most commonly seen in boys in the pineal region and girls in the suprasellar region
80
What can germinomas secrete?
HCG- precocious puberty
81
What is associated with pineoblastoma?
retinoblastoma (3rd place of retiunoblastoma)
82
Lhermitte-Duclos is associated with?
Cowden Syndrome
83
Most sensitive sequence for subarachnoid hemorrhage?
FLAIR
84
Le Forte 1
lateral nasal aperture
85
LeFort 2
Inferior orbital rim and floor
86
LeFort 3
Zygomatic Arch and lateral orbital rim/wall
87
ZMC fracture
involves the zygoma, inferior and lateral orbit
88
Longitudinal Temporal Bone Fracture
Comes from lateral Ossicular dislocation, conductive hearing loss
89
Transverse Temporal Bone Fracture
Sensorineuronal hearing loss Facial nerve damage
90
Acute
1-3 days Deoxyhemoglobin
91
Early Subacute
\>3 days Intracellular methemoglobin
92
Late subacute
\>7 days Extracellular methemoglobin
93
Chronic
\>14 days Hemosiderin
94
Symptoms of superficial siderosis
sensorineural hearing loss and ataxia
95
Watershed infarcts in child, most common cause?
Moyamoya
96
How long is diffusion restriction positive for in CVA
30 minutes- 2 weeks If FLAIR is not hyperintense, think less than 6 hours
97
When does stroke enhance?
3 days-3 months
98
Sequela of Venous Sinus thrombosis
Dural AVF Increased CSF pressure
99
Most common site of aneurysm?
Anterior Communicating Aneurysm
100
Pedicle Aneurysm?
Aneurysm on the feeding artery of the AVM
101
Most common site of mycotic aneurysms?
Distal MCA
102
Increased risk of AVM hemorrhage
3% per year Small size of AVM (increased pressure) Single draining vein Aneurysm associated with nidus Basal Ganglia, thalamic, periventricular location
103
Classic symptoms of dural venous fistula?
Pulsatile tinnitus if involving the superior sagittal sinus, assocaited with venous thrombosis May be occult and require angio
104
DVA associated with?
cavernous malformation (cavernoma)
105
Cavernoma?
No normal intervening brain matter Angio occult, low flow lesion
106
Capillary Teleangectasia?
NO increased risk of hemorrhage, "brush like" Does have normal intervening brain parenchyma Can develop as complication of radiation therapy
107
When does vasospasm associated with subarachnodi hemorrhage happen?
4-14 days after Other causes of vasospasm- Meningitis, PRES, MIgraine
108
What systemic vasculitis involves the intracranial arteries?
PAN Temporal arteritis, wegners, takayasu Other causes: cocain, RA/SLE, lyme
109
Moyamoya associations?
Sickle Cell, Neurofibromatosis, prior radiation, Down's Syndrome
110
CARDASIL spares the ______ lobes?
Occipital lobes are spared Autosomal dominant- presents as headache and progresses to dementia -White matter chages- predominately in the temporal lobes
111
Formula for carotid artery stenosis?
1- A(maximal narrowing)/B (distal ICA) x 100
112
Colpocephaly?
Colpocephaly = Disproportionate dilation of the occipital horns --\> corpus callosal agenesis --\> CC agenesis is most common anomaly associated with other CNS malformations CC agenesis- Can also present as steer horn ventricles or parallel ventricles CC agenesis/dysgenesis is associated with Lipomas
113
Anencephaly Findings?
AFP is elevated, polyhydramnios
114
Iniencephaly
Deficit of the occipital bones, enlarged foramen magnum May have incomplete formation of cervico-thoracic vertebrae "star gazing fetus"-face turned upward, hyper-extended cervical spine
115
Molar Tooth Sign?
Joubert Syndrome -Superior cerebellar peduncles are thin and the vermis may be incomplete or absent
116
Joubert is associated with?
Retinal dysplasia, multicystic dysplastic kidney
117
Torcular-Lamboid Inversion?
Dandy-walker malformation - Absent vermis - Cyst communicates with the 4th ventricle
118
Blake Pouch
Cyst below or posterior to vermis (which is normal) Posterior fossa is not enlarged but the tentorium is elevated
119
Mega-Cisterna Magna
Retro-cerebellar CSF space \> 10 mm Normal cerebellum
120
Lobar holoprosencephaly
Absent septum pellucidum Can have fusion of frontal lobes
121
Semi-lobar holoprosencephaly
Fusion of thalami Olefactory bulbs and tracts are absent
122
Alobar Holoprosencephaly
Single large ventricle with fusion of thalami and basal ganglia No falx or CC
123
Meckel- Gruber Syndrome
Trias: holoprosencephaly, renal cysts, polydactly
124
Big ventricle and cerebral hemisphere?
Hemimegalencephaly DDX: Rasmussen's encephalitis- the smaller hemisphere has the big ventricle due to atrophy
125
What is associated with schizencephaly (open lip /close lip)?
Optic nerve hypoplasia absent septum pellucidum Epilepsy
126
Hydranencephaly will have?
Falx, due to in utero insult Cortical mantle is absent (severe hydrocepahlus will have a cortical mantle)
127
Klippel Fiel Syndrome is associated with?
Chiari I malformation
128
Scaphocephaly (dolichocephaly) is fusion of?
Sagittal sutures
129
Plagiocephaly is fusion of?
Unilateral coronal suture, Harlequin eye
130
Trigonocephaly is fusion of?
metropic suture (suture between frontal bones)
131
Brachcephaly is fusion of?
Coronal or Lambdoid sutures
132
Aperts syndrome?
Brachycephlay + fused fingers
133
Crouzons
Brachcephaly + First arch hypoplasia (maxilla, mandible)
134
Cleidocranial Dysostosis
Brachycepahly + Wormian bones + absent clavicles
135
Most common cranniosynostosis?
Sagittal- dolicocephaly
136
Turricephaly?
fusion of coronal and lambdoid sutures
137
What is associated with Piriform aperture stenosis (narrowing at opening of nose)?
hypothalamic-pituitary- adrenal axis dysfucntion
138
MELAS has what abnormalities on Spectroscopy?
increased lactate, decreased NAA
139
Canavans has elevated _____ on spectroscopy?
NAA Also have diffuse involvement of the bilateral subcortical U fibers
140
Alexanders Leukodystrophy is associated with?
Frontal white matter involvement
141
Metachromatic Leukodystrophy Findigns?
Most common leukodystrophy Dark spots in demylianted perventricular white matter, TRIGOID appearence
142
Adreno-Leukodystrophy presents with?
Symmetric involvement of the splenium and corpus callosum as well as occipital lobes Only occurs in boys
143
In spectroscopy, myoinositol is elevated with?
Alzhemiers and low grade glioma
144
Alanine is elevated in?
Meningiomas
145
Radiation necrosis pattern?
Choline decreased, NAA down, Lactate up
146
What is elevated in hepatic encephalopathy?
Glutamine
147
Cholesterol Granuloma on MR?
At petrous apex typically T1 and T2 bright DDX: congenital cholesteotoma
148
Congenital cholesteotoma on MR?
Petrous apex T1 dark, T2 bright, RESTRICTS diffusion
149
Grandenigo Syndrome symptoms and involves?
Complication of apical petrositis when Dorello's canal is involved (CN6) Lateral rectus palsy, otomastoiditis, and facial pain (trigeminal nerve involvement)
150
Endolymphatic sac tumors are assocaited with?
Von- Hippel-Lindau Tumors have amorphous calcifications, T2 bright, enhance
151
Paragangliomas of the jugular fossa most commonly present with?
Hoarseness- vagal nerve involvement Tumor- salt and pepper appearence, highly vascular
152
Large vestibular aqueduct syndrome?
Vestibular aqueduct connects vestibule to the endolymphatic sac Enlarges \> 1.5 mm- associated with progressive sensorineural hearing loss Associated with absence of bony modiolus
153
Types of otosclerosis?
Fenestral- involves the fissula ante fenestram Retro-fenestral- demineralization around the cochlea, typically bilateral and symmetric Conductive hearing loss in female- typical presentation
154
Acquired Cholesteotoma will first errode? What is the most common ossicle to be erroded?
The scutum eroded first Long process of the incus is most common segment of ossicular chain to be eroded Cholesteotoma involves Prussak's space Can have fistula to the lateral semicircular canal
155
Most common type of acquired cholesteotoma?
Pars flaccida (other is pars tensa)
156
Noise induced vertigo is associated with?
Dehiscence of the superior semicircular canal
157
Most common cause of necrotizing external otitis?
Diabetes with pseudomonas infection
158
Which portions of the facial nerve do not normally enhance?
cisternal, cannilicular, labyrinthine
159
What can cause abnormal cranial nerve VII enhancement?
Bell's palsy, lymes, Ramsay Hunt, perineural tumor spread
160
What T-bone fracture is most likely to injure CNVII?
Transverse
161
Which is typically midline Chordoma or Chondrosarcoma?
Chordoma
162
What is the blood supply to the juvenile nasal angiofibroma?
Internal maxillary
163
Where is the JPA centered typically?
sphenopalantine foramen can expand the pterygopalantine foramen
164
Antrochoanal polyp arises in?
Maxillary sinus enlarges maxillary sinus ostium associated with nasal congestion and obstruction
165
Inverting papilloma arise from?
Lateral wall of the nasal cavity, frequently close to middle turbinate MRI- cerebriform pattern, look like mini-brain 10% harbor squamous cell carcinoma
166
Enthisioneuroblastoma originate?
Cribiform plate-\> grow superiorly into the skull and down throught the sinus typically has cystic components, avid homogenous enhancement
167
What nasal tumor is positive on octreotide scan ?
Enthesioneuroblastoma
168
Most common site of squamous cell carcinoma?
Maxillary sinus
169
Epistaxis treatment?
IF posterior and compression does not work Embolize the sphenopalantine artery off the internal maxillary artery (evaluate for anastamosis between ECA and opthalamic)
170
Where does a rannula arise?
sublingual gland
171
Rannula is considered diving once it is below?
mylohyoid muscle
172
Sialolithiasis most commonly involves the?
Submandibular gland whartons duct
173
Spread of infection in the mouth is dictated by?
The mylohyoid muscle Above goes into the sublingual space Below goes into the submandibular space
174
What causes osteonecrosis of the mandible
prior radiation or bisphosphonate use
175
Causes of pulsatile exophthalmos?
CC fistula NF1 with sphenoid wind dysplasia
176
Dacrocysticits is?
Inflammation and dilation of the lacrimal sac
177
Most commonly affected extraoccular muscles in thyroid opthalmopathy?
IMSLO - inferior rectus \> medial \>superior rectus \> lateral rectus \> Superior oblique Painless, does not involve the tendon
178
What divides the superficial and deep lobes of the parotid gland?
CN VII (retromandibular vein is medial to CN VII)
179
Most common salivary gland tumor?
Pleomorphic adenoma- T2 bright with rim of low signal small malignant potential
180
What are features of a warthin tumor?
Usually cystic Male smoker Bilateral Take up Pertechnetate
181
Mucoepidermoid Carcinoma
Most common malignant tumor of minot salivary glands associated with radiation
182
Which salivary gland tumor has increased propensity for perineural tumor spread?
Adenoid cystic carcinoma
183
Lymphoma of the parotid glands has a higher incidence in what population?
Sjogrens
184
Most common viral cause of parotitis?
Mumps
185
HIV patient with bilateral mixed cystic and solid parotid lesions?
Benign lymphoepithelial disease
186
"Honeycombed" parotid gland?
Sjogrens (associated with MALT lymphoma)
187
Carotid space contains?
Carotid artery, jugular nerve, CN IX, CN X, and CN XI
188
Paragangliomas take up what radiotracer?
octreotide
189
Most common paragangliomas?
Carotid Body- splays ECA/ICA Glomus Jugulare- jugular foramen Glomus Vagale- above carotid and below jugular foramen Glomus tympanicum- overlies cochlear promontory
190
Massicator Space Contains?
masticator, temporalis, medial and lateral ptyergoids, inferior alveolar nerve
191
Most common cause of massicator space mass?
odontogenic infection
192
Retropharyngeal space extends down to?
T3
193
Common causes of retropharyngeal lymph nodes?
SCC, papillary thyroid carcinoma, lymphoma
194
Bacterial cause of lemierre's?
Fusobacterium Necrophorum
195
A mass in what location would displace the parapharyengeal fat medially?
parotid carotid mass- displace anterior Superficial Mucosa- displace laterally Massicator space mass would displace posteriorly
196
What separates 1A lymph nodes from 1B?
anterior belly of digastric
197
Separates 1B from 2A?
stylohyoid
198
Separates 2A from 2B?
Spinal accessory nerve
199
Separates level 2 from level 3?
inferior hyoid
200
separates level 3 from level 4?
lower border of cricoid
201
Fixation of the vocal cords and paraglottic space involvement indicate what level laryngeal cancer?
T3
202
What determines surgical resection candidacy for laryngeal conservation?
Invasion of the cricoid
203
Discontinuity of the posterior globe?
Coloboma
204
Coloboma is associated with which syndrome?
CHARGE
205
"martini glass globe"?
Persistent Hyperplastic primary vitreous can lead to retinal detachment
206
Coat's disease
retinal teleangestasia with subretinal exudate (does not calcify like retinoblastoma)
207
Optic nerve glioma is associated with?
NF1 Global enlargement of the entire nerve WHO Grade I pilocytic astrocytomas
208
"tram track" calcifications of the optic nerve?
meningioma
209
Orbital Pseudotumor facts?
unilateral, painful, does not spare myotendinous junction most commonly involves lateral rectus
210
Inflammatory process in the cavernous sinus?
Tolosa Hunt
211
Lymphocytic hypophysitis?
Enlarged enhancing pituitary stalk and pituitary Can be T2 bright with dark surrounding rim Most common- 3rd trimester or post-partum
212
Most common location of occular dermoid?
Superior and lateral (arise from the frontozygomatic suture)
213
Appearance of metastatic breast cancer to the orbit?
desmoplastic reaction resulting in enophthalmos
214
Lymphoma of the orbit is associated with?
Chlamydia Psittaci Frequently involves the lacrimal gland
215
Most common intra-occular lesion in an adult?
Melanoma Invasion of Bruchs membrane- evaluate for
216
Quadrilateral Retinoblastoma?
both eyes, pineal, and suprasellar
217
Lymphangioma of the orbit?
Multi-spatial Fluid-fluid levels on MRI Do not increase with valsalve
218
Most common cause of spontaneous orbital hemorrhage?
varix, distend with provocative maneuvers
