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Flashcards in 3. Neuropathology Deck (58)
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1

Primary brain vesicles

Forebrain (prosencephalon) - tele and dien
Midbrain (mesencephalon) - mesen
Hindbrain (rhombencephalon) - meten and myelen

2

Secondary brain vesicles

Telecephalon
Diencephalon
Mesencephalon
Metencephalon
Myelencephalon

3

Primary neurulation

Formation of neural plate (day 18-19)
Neural folds (20-21)
Closure of neural tube (22)
Rostral then caudal

4

Secondary neurulation

Development of neural tube (day 28)
species specific

5

What spinal level does spinal cord end during prenatal life at 12 week, 15 week and 24 week?

C5, S3, S1

6

What spinal level does spinal cord end at newborn and adult life?

L3, L1-2 (end of dura/arachnoid sac at S2)

7

Tissue repair in fetus vs adult brain

Macrophages cause phagocytosis (without gliosis) -> pseudoprimary malformation
(hydranencephaly or porencephalic cyst before or at early 2nd trimester)

8

Subependymal germinal matrix hemorrhage occur in which population?

Prematurely born (<1500 kg) within 3 days after delivery

9

Pathogenesis of germinal matrix hemorrhage?

Periventricular area with fragile microcirculation stroma
Hypoxic stress -> autoregulation fails and excessive perfusion ruptures GM microcirculation

10

Grades of GM hemorrhage

I confined in GM
II filling lateral ventricles
III with distention
IV parenchyma

11

Usual location of GM hemorrhage

Head of caudate > thalamus > behind foramen of monro

12

Where do contusions occur most frequently?

Frontal and temporal lobes

13

Traumatic epidural hematoma source of bleeding?

Middle meningeal artery
Less common: laceration of venous sinus (transverse sinus from occipital fracture)

14

Duret hemorrhage?

Delayed upper brainstem hemorrhage from rapidly evolving descending transtentorial herniation

15

Pathophysiology of Duret hemorrhage

Stretching/laceration of pontine perforating branches of basilar artery

16

Diffuse axonal injury?

Axonal damage
parasagittal white matter, corpus callosum, internal capsule, cerebellar peduncles

17

Duret hemorrhage vs brainstem small tissue-tear hemorrhages in DAI?

Both in upper brainstem, but Duret is delayed and in paramedian areas, whereas DAI located in dorsolateral brainstem

18

Microscopic timeline picture of DAI?

2-12h
Axonal swellings (beta-amyloid precursor protein), then axonal disconnection, then microglial clusters around degenerating axons (5-10 days)

19

Classify DAI

I: frontal/temporal, cerebellar and internal capsule
II: corpus callosum (splenium)
III: brainstem/cerebellar peduncles and corticospinal tracts

20

Biochemical changes in DAI

1h: neurofilament immunoreactivity
4-5: accum of bAPP
6h: ubiquitin
1d-2m: axonal swelling
2m-y: wallerian degeneration/demyelination

21

Which type of temporal bone fracture results in conductive hearing deficit?

Longitudinal temporal bone fracture

Transverse causes more direct nerve damage ith sensorineural hearing deficit (more forceful)

22

Most striking microscopic finding in lisencephaly type I?

Cortex made from 4 layers (molecular - external neuronal - cellular - internal nuronal)

23

Macroscopic and microscopic picture of mesial temporal lobe (hippocampal sclerosis)

Ammon's horn sclerosis
Macroscopic: hippocampus smaller than other side, enlarged temporal horns

Microscopic: neuronal loss in CA1, gliosis

24

Rasmussen syndrome

Rare disorder in children
Progressive unilateral neurologic deficit + sudden onset epilepsy refractory to medical treatment.
Hemiplegia, hemianopsia, intellectual deterioration

25

Microscopic picture of Rasmussen syndrome

Like chronic viral encephalitis - lymphocyte cuffs around blood vessels, microglial nodules

26

What are rosenthal fibers

Eosinophilic bodies
See in neoplasms (juvenile pilocytic astrocytomas), around craniopharyngiomas, multiple sclerosis plaques, Alexander disease

27

Classifications of astrocytomas

Grade 1 (juvenile pilocytic): GFAP staining, rosenthal fibers
Grade 1 (subependymal giant cell): assoc. with tuberous sclerosis
Grade 2 (diffuse): nuclear atypia but no mitosis, moderately increased cellularity
Grade 2 (pleomorphic xanthoastrocytoma): pleomorphic lipidized cells in bg of reticulin network)
Grade 3 (Anaplastic): nuclear atypia and mitosis
Grade 4 (GM): nuclear atypia, mitosis, microvascular proliferation and necrosis
Grade 4 (Gliomatosis cerebri): extensively diffuse at least 3 lobes, superficial and/or deep gray matter

28

Primary vs secondary glioblastoma

Primary (age>55, males) - EGFR overexpression, PTEN
Secondary (younger, women) - 2/3 TP53 mutations and no EGFR amplifications

29

Colloid cysts

Usually anterior 3rd ventricles
Glistening cysts with mucin - outer fibrous connective tissue capsule lined by ciliated pseudostratified epithelium, PAS+ mucin

30

Craniopharyngioma histology

Squamous epithelium, keratin