NEURO 3 Flashcards

1
Q

Order of myelination

A
  • inferior to superior
  • posterior to anterior
  • central to peripheral
  • sensory then motor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

last structures to myelinate

A

subcortical white matter (occipital at 12 months, frontal at 18 months)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

structures that are myelinated at birth

A
  • posterior limb of internal capsule
  • brainstem
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

order of sinus formation

A

maxillary –> ethmoid –> sphenoid –> Frontal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what structures are in the superior orbital fissure

A

CN 3, CN4 ,CN V1, CN6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what structures are in the inferior orbital fissure

A

V2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What structure can get compressed with a subfalcine herniation

A

The cingulate gyrus is herniated under the falx, and if progression occurs, other areas of the frontal lobe are involved

Complications

hydrocephalus due to obstruction of the foramen of Monro

anterior cerebral artery (ACA) territory infarct due to compression of ACA branches, specifically the pericallosal artery

focal necrosis of the cingulate gyrus due to direct compression against the falx cerebri

ACA infarction occurs as the cingulate sulcus extends under the falx dragging the ipsilateral anterior cerebral artery with it. If this becomes compressed against the falx, distal anterior cerebral artery infarction can occur, the most common clinical manifestation being contralateral leg weakness.

In subfalcine herniation, the degree of midline shift correlates with the prognosis; less than 5 mm deviation has a good prognosis, whereas a shift of more than 15 mm is related to a poor outcome 4.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

disseminated necrotizing leukoencephalopathy

A
  • seen in leukemia patients getting radiation and chemo
  • severe white matter changes, with ring enhancement
  • can be fatal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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+
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Cortically based tumors

A

PDOG

  • pleomorphic Xanthoastrocytoma
  • Dysembryoplastic Neuroepithelial tumor (DNET)
  • Oligodendrogliomas
  • Gangliogliomas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q
A

Pleomorphic Xanthroastrocytoma (PXA)

  • 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

https://radiopaedia.org/articles/pleomorphic-xanthoastrocytoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Ganglioglioma

A
  • low grade; can enhance
  • can occur at any age
  • usually temporal lobe
  • cystic and solid mass with focal calcification
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

intraventricular tumors - arising from choroid plexus

A
  • choroid plexus papilloma
  • choroid plexus carcinoma
  • xanthogranuloma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What syndromes are associated with medulloblastomas?

A
  • Basal cell nevus
  • Turcot’s syndrome
  • Gorlin syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Gorlin syndrome

A
  • medulloblastoma
  • dural calcification
  • basal skin cancer after radiation
  • odontogenic cysts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

most common intraventricular mass in an adult 20-40 years old

A

central neurocystoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Cerebellopontine angle masses

A

schwannoma (75%)
menignioma
epidermoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Infratentorial tumors

A
  • AT/RT
  • medulloblastoma
  • ependymoma
  • JPA
  • Hemangioblastoma
  • ganglioglioma
  • Diffuse Pontine glioma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Supratentorial tumors

A
  • Mets
  • Astrocytoma
  • Gliomatosis cerebri
  • oligodendroglioma
  • primary CNS lymphoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

hemangiopericytoma

A

soft tissue sarcoma that can mimic an aggressive meningioma because both enhance homogeneously

  • will not calcify or cause hyperostosis
  • will invade the skull
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

signal of blood on MRI

A
  • 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)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

most sensitive sequence for subarachnoid hemorrhage

A

FLAIR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Iniencephaly

A

star gazing fetus: upturned face, hypextended C-spine, short neck
- deficit of occipital bones, resulting in an enlarged foramen magnum

32
Q

Joubert syndrome associations

A
  • elongated superior cerebellar peduncles
  • small or aplastic vermis
  • absence of pyramdial decussation
  • strong assocaition with retinal dysplasia
  • association with multicystic dysplastic kidney
33
Q

Meckel Gruber syndrome

A
  • occipital encephalocele
  • multiple renal cysts
  • polydactyly
  • strong association with holoprosencephaly
34
Q

Associations with holoprosencephaly

A
  • single midline monster eye
  • solitary median maxillary incisor
  • pyriform aperture stenosis (From nasal process overgrowth)
35
Q

schizencephaly associations

A
  • optic nerve hypoplasia
  • absent septum pellucidum
  • epilepsy
36
Q

Chiari 1 malformation association

A

Klippel Feil syndrome

37
Q

Apert’s

A

brachycephaly + fused fingers

38
Q

Crouzon’s

A

brachycephaly + first arch (maxilla and mandible) hypoplasia

39
Q
A

brachycephaly + wormian bones + absent clavicles

Abstract

Cleidocranial dysplasia:

  • AD skeletal dysplasia
  • abnormal clavicles,
  • patent sutures and fontanelles,
  • supernumerary teeth,
  • short stature,
  • and a variety of other skeletal changes.
  • The disease gene has been mapped to chromosome 6p21 within a region containing CBFA1, a member of the runt family of transcription factors.

Typical clinical and radiological findings in CCD. (A) Facial appearance in a 6 month old boy. Note large, brachycephalic skull, frontal and parietal bossing with large anterior fonanelle, and the appearance of a small face. Other characteristic features include widely spaced eyes, low nasal bridge, reduced nasal length, but increased nasal width and protrusion. (B) Chest radiograph showing cone shaped thorax and left clavicular hypoplasia and aplasia on the right side. (C) Pelvic abnormalities in a 4 year old girl. Note hypoplasia of the iliac wings, broad femoral necks with large epiphyses, and unossified symphysis pubis. (D) Hand radiograph of a 2½ year old female showing hypoplastic distal phalanges, accessory epiphyses of the second metacarpal, and long second metacarpal. (E) Pantomographic view of the permanent dentition of a 16 year old female. Note multiple, unerupted, supernumerary teeth.

https://jmg.bmj.com/content/36/3/177

40
Q

MELAS

A

mitochondrial encephalomyopathy, lactic acidosis, and stroke like episodes
on MR spectroscopy: increased lactate; decreased NAA

  • CT
    • multiple infarcts
      • involving multiple vascular territories
      • may be either symmetrical or asymmetrical
      • parieto-occipital and parieto-temporal involvement is most common
    • basal ganglia calcification 1,2
      • more prominent feature in older patients
    • atrophy 2
  • MRI
    • acute infarcts
      • swollen gyri with increased T2 signal
      • may enhance
      • subcortical white matter involved
      • increased signal on DWI (T2 shine through) with little if any change on ADC: thought to represent vasogenic rather than cytotoxic oedema 3
    • chronic infarcts
      • involving multiple vascular territories
      • may be either symmetrical or asymmetrical
      • parieto-occipital and parieto-temporal most common
    • MR spectroscopy:
      • may demonstrate elevated lactate in otherwise normal appearing brain parenchyma or in CSF 3,4.
  • Case courtesy of Dr Mustafa Takesh, Radiopaedia.org, rID: 78355
41
Q

most common leukodystrophy? what does it look like?

A
  • *Metachromatic
  • diffuse white matter involvement with tigroid apperance**

Metachromatic leukodystrophy (MLD) is the most common hereditary (autosomal recessive) leukodystrophy and is one of the lysosomal storage disorders. It has characteristic imaging features including peri-atrial and to a lesser extent frontal horns leukodystrophy as well as periventricular perivenular sparing results in “tigroid pattern” on fluid-sensitive MRI sequences.

Epidemiology

Metachromatic leukodystrophy has an estimated prevalence of ~1:100,000 and typically manifests between 12 to 18 months of age. The disease can sometimes be classified according to the time of onset:

late infantile: most common ~65% (range 50-80%)

juvenile (onset between 3-10 years)

adult (after age 16)

https://radiopaedia.org/articles/metachromatic-leukodystrophy

42
Q

High NAA peak

A

Canavan’s disease

Canavan disease is rare genetic neurological disorder characterized by the spongy degeneration of the white matter in the brain. Affected infants may appear normal at birth, but usually develop symptoms between 3-6 months of age.

Canavan disease, also known as spongiform degeneration of white matter (not to be confused with Creutzfeldt-Jakob Disease) or aspartoacylase deficiency, is a leukodystrophy clinically characterised by megalencephaly, severe mental and neurological deficits, and blindness.

Epidemiology

Canavan disease is particularly common in the Ashkenazi Jewish community 1. The carrier frequency among the Ashkenazi ranges from 1:37 to 1:57, with a corresponding prevalence of 1 in 6000-14000 in this high risk group1. In the general population the prevalence is 1 in 100000 11.

Clinical features

There are a wide range of clinical features, but generally there is a progression from lethargy and hypotonia, to macrocephaly (due to underlying megalencephaly) and spasticity, to blindness and seizures, to decerebrate posturing and eventual death 2. In the vast majority of patients, clinical onset is in infancy with death before 5 years of age, and often before 18 months, but juvenile-onset forms of the disease have also been reported 2. Juvenile-onset forms may have speech difficulty, mild intellectual impairment and suffer neurological regression 11.

Pathology

It is an autosomal recessive disorder due to a gene mutation on the short arm of chromosome 17 leading to deficiency of N-acetylaspartoacylase, a key enzyme in myelin synthesis, with resultant accumulation of N-acetylaspartate (NAA) in the brain, cerebrospinal fluid, plasma, and urine 3,4. Although its effects are widespread, it has a predilection for subcortical U-fibres and Alzheimer type II astrocytes in the gray matter 3,5.

Markers

Increased levels of NAA in the urine may be detected 11.

Radiographic features

In Canavan disease the neuroimaging findings are diagnostic of the condition 11.

CT

The oedematous sponginess of the white matter causes a characteristically low radiographic attenuation on CT so that it stands out from the relatively unaffected gray matter 4. Megalencephaly may also be also noted depending on the clinical stage 4.

MRI

MRI confirms the megalencephalic appearance and provides more detail of the white matter disease, which is typically diffuse, bilateral, and involving the subcortical U-fibres 4-8,11:

T1: areas of low signal

mainly within subcortical white matter

generally with sparing of the corpus callosum, caudate nucleus, putamen and internal capsule

as the condition progresses atrophy of the periventricular white matter may be seen with associated ventriculomegaly

globi pallidi and thalami are usually affected as well

T2/FLAIR: findings as above except for areas of high signal in the affected white matter

DWI: restricted diffusion within the diseased white matter

MR spectroscopy: markedly elevated NAA and NAA:creatine ratio are pathognomonic for the condition 11.

this can be remembered using the mnemonic CaNAAvan

There is no enhancement of affected regions on either CT or MRI 5-8.

Treatment and prognosis

The condition is fatal with death resulting at 2-5 years and treatment is generally supportive 4. No effective treatment is yet available 4. However, genetic therapies are being trialled and seem to reduce the level of NAA within the brain 11.

43
Q

TE needed to invert the lactate peak

A
intermediate TE (140) 
at long TE (280) - lipid and lactate double peak seen
44
Q

elevated myoinositol peak

A

Alzheimer’s disease

45
Q

elevated alanine peak

A

meningiomas

46
Q

elevated glutamine

A

hepatic encephalopathy

47
Q

high grade tumor: what does the MRS look like?

A
  • elevated choline, lactate, and lipids
  • decreased NAA
48
Q

low grade tumor: what does the MRS look like?

A
  • decreased choline, NAA
  • elevated inositol
49
Q

MRS in radiation necrosis

A
  • decreased choline and NAA
  • increased lactate
50
Q

Gradenigo syndrome

A

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
Q

what is the main blood supply to the posterior nose

A

sphenopalatine artery (terminal internal maxillary artery)

52
Q

most common masticator space “Mass”

A

odontogenic abscess

53
Q

order of muscle involvement in Grave’s orbitopathy

A

inferior rectus –> Medial rectus –> superior rectus –> lateral rectus –> superior/inferior obliques (IM SLO)

54
Q

ACR recommendations prior to lumbar puncture (regarding anticoagulation)

A
  • 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
Q

Currarino triad

A
  • sacrococcygeal osseous defect (scimitar sacrum)
  • anorectal malformation
  • anterior sacral meningocele
56
Q

Foix Alajouanine syndrome

A

myelopathy associated with a dural VF

57
Q

What are the different types of Amyloid Angiopathy?

A
  • A spectrum of amyloid disorders patholgoically defined as deposition of amyloid within the brain vessels.
    • CEREBRAL AMYLOID ANGIOPATHY (CAA)
      • without inflammation
    • AB - RELATED ANGIITIS (ABRA)
      • vascular angiodestructive inflammation
    • CEREBRAL AMYLOID ANGIOPATHY RELATED INFLAMMATION
      • CAA-RI
      • Perivascular inflammatory change without angiodestructive process.
58
Q

What are the characteristics of Cerebral amyloid angiopathy?

A
  • Deposition of Amyloid in vessel walls
  • Not Synonymous with AD, can be an exclusive dx.
  • Increased Risk for sig Hx
    • Peripheral Microhx
    • Lobar Hemorrhage
    • superficial siderosis.
59
Q

What are the imaging findings of CAARI and ABRA?

A
  • Leptomeningeal enhancement common
    • 10x greater likelihood that simple CAA
  • CAARI: Confluent subcortical +/- cortical edema
    • parietal and temporal lobes more frequent
  • May be unifocal or multifocal. Often asymmetric
  • Microhemorrhages tend to be more frequent in areas of edema
  • Much less likely to have lobar hemorrhage than CAA
60
Q
A

Circumferential vessle wall enhancement with surrounding micro hemorrhages.

https://www.asnr.org/education/neurocurriculum-live/

61
Q
A

Leptomeningeal enhancement within the central sulcus on post contrast flare and post contrast T1W imaging.

SWI shows evidence of prior lobar hx in the right frontal libe and superficial siderosis and peripheral micro hx

https://www.asnr.org/education/neurocurriculum-live/

62
Q

What is the most common Dementia syndrome?

A
  • Alzheimers’ Dementia
  • Amyloid + Tau disorder
    • Amyloid alone is insufficient to cause significant neuronal damage
    • Tau deposition is likely the culprit for neuronal loss

https://www.asnr.org/education/neurocurriculum-live/

63
Q

Discuss the progression of the disease of Alzheimers re Amyloid, tau, FDG and MRI correlating with symptoms

A
  1. Cog impairment increases over time
  2. Amyloid deposition proceeds CI by many years, and in many may be asymptomatic
  3. Tau deposition occurs
  4. around the same time FDG hypometabolism occurs
  5. MRI positive findings of atrophy then occur

https://www.asnr.org/education/neurocurriculum-live/

64
Q

What does this show?

A

TOP LEFT: diffuse/generalised Amyloid deposition

TOP RIGHT and BOTTOM LEFT: more regional deposition of Tau, temporal/parietal

BOTTOM RIGHT: temporal lobe and parietal lobe atrophy on MRI

https://www.asnr.org/education/neurocurriculum-live/

65
Q

What are the typical imaging features of Alzeihmers on MRI?

A
  • T1W sequences
    • Coronal:
      • profound mesial temporal lobe volume loss
        • hippocampus
        • entorhinal cortex
      • Asymmetry of the left sylvian fissure
    • Parasagittal
      • Pre-cuneus atrophy disproportionate to the rest of the brain
66
Q

Whats the dx?

A
  • Marked atrophy over two years with a striking posterior predominance. ? AD vs DLB.
  • FDG PET
    • Asymmetric primary posterior hypo metabolism
  • Amyloid PET (FLORBETPIR)
    • Showed amyloid deposition
  • Ioflupane scan done
    • Reduced striatal binding
  • OVERALL:
    • This patient has dementia with Lewy bodies
    • DLB is often amyloid positive
    • So the amyloid scan may not be very useful

https://www.asnr.org/education/neurocurriculum-live/

67
Q
A

Posterior cortical atrophy (PCA), also called Benson’s syndrome, is a rare, visual variant of Alzheimer’s disease. It affects areas in the back of the brain responsible for spatial perception, complex visual processing, spelling and calculation.

68
Q
A

Persons with logopenic variant primary progressive aphasia (lvPPA) have increasing trouble thinking of the words they want to say. As time goes on, people with lvPPA have more trouble getting the words out, and they eventually begin to speak slower and slower.

What Causes lvPPA?

The cause of lvPPA is unknown. Scientists know that in lvPPA there is a large build-up of proteins called amyloid and tau within brain cells, which are the same proteins that build up in Alzheimer’s disease. These proteins occur normally, but we do not yet understand why they build up in large amounts. As more and more proteins form in brain cells, the cells lose their ability to function and eventually die. This causes the affected parts of the brain, most often the left posterior temporal cortex and inferior parietal lobe, to shrink.

https: //memory.ucsf.edu/dementia/primary-progressive-aphasia/logopenic-variant-primary-progressive-aphasia
https: //www.asnr.org/education/neurocurriculum-live/

69
Q

What is Dementia. with Lewy Bodies?

A
  • Possibly the second most common form of dementia
  • may be difficult to distinguish from AD in early disease
    • Autopsy study:
      • 50% of patients with living dx of DLB had AD on Autropsy
  • A-synucleinopahty
    • majority also show amyloid deposition

https://www.asnr.org/education/neurocurriculum-live/

70
Q

Signs of DLB on FDG PET?

A
  • Cingulate Island
    • posterior hypometabolism with sparing of the cingulate cortex.
  • Occipital Tunnel
    • sparing of the calcarine cortex
  • DatScan
    • reduced striatal binding
71
Q
A
  • Primary progressive aphasia
    • Heterogenous group of neurodegenerative disorders characterised by progressive language deficit
  • Subtypes
    • Non-fluent or agrammatic (navPPA)
    • Semantic (svPPA)
    • Logopenic (lvPPA)
  • Although grouped together, the clinical symptoms, imaging and pathology are very different.
72
Q

What are the different types of Primary Progressive Aphasia and their MRI Signs

A

Nonfluent navPPA

Logopenic Lv PPA

Semantic Sv PPA

73
Q

Label which Primary progressive aphasia types these are:

A
  1. navPPA
    • nonfluent variant
    • Dominant hemisphete frontal lobe hypometabolism and atrophy which frequently extends to involve the temporal lobe later in the course of the disease
  2. SvPPA
    • Asymmetric dominant lobe atrophy and hypometabolism in the temporal pole
  3. LvPPA
    • dominate hemisphere hypometabolism temporal lobe/ posterior para sylvian and temporal lobe distribution
74
Q
A
  • Patient 3
    • Profound hippocampal volume loss
    • Relative Preservation of the entorhinal cortex
    • Frontal lobe atrophy slightly more prominent than that of the paramedic parietal lobe
    • Patient cognitively intact despite profound volume loss
    • Amyloid pet scan (left picture)
    • Showed normal white matter binding
    • Right picture shows abnormal cortical binding
  • LATE:
    • Profound hippocampus damage (CA1) as well as in the subiculum, entorhinal cortex and amygdala
    • ? Sunomymous with hippocampal sclerosis of aging.
    • Hipoocampal sclerosis unilateral in 40-50%
    • Hippocampal atrophy usually greater than those with Pure AD. Often asymmetric
    • Combo of AD and LATE had greater hippocampal atrophy than those with only AD.
    • Also atrophy in the frontal anterior temporal and insular cortices.
    • Corresponds with the distribution of TDP-Proteinopathy on autopsy
    • Typically >75 years
    • profound mesial temporal atrophy, even greater with coexistent AD pathology.
    • May have little cognitive impairment, MCI or severe demented (typically with +AD)
    • Often asymmetric MTL atrophy (L>R in my experience)

https://www.asnr.org/

75
Q
A