Neurology I Flashcards Preview

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Flashcards in Neurology I Deck (71):
1

Neural plate development mechanism

Notochord induces overlying ectoderm to differentiate into neuroectoderm and form neural plate --> neural plate gives rise to neural tube and neural crest cells.

2

What are neural crest cells derived from?

Neural plate

3

Hindbrain gives rise to..

mesencephalon + myelencephalon

4

CNS embryology

Code: /forebrain telencephalon + diencephalon. Eagle with talons into cerebral hemispheres on wall on left + between two ventricles/telencephalon cerebral hemispheres + lateral ventricles. Pile of dice on wall on left + Kai thaler on sitting on top + aqueduct lined with ham/diencephalon thalamus + third ventricle. Meso soup on wall across + brain in the middle + aqueduct behind it lined with brains/mesencephalon midbrain + cerebral aqueduct. /hindbrain metencephalon + myelencephalon. Metropolitan museum of art in right corner + pond in front of it + bell hanging above pond + covered in hair/metencephalon pons and cerebellum + 4th ventricle. Mylo in front of hair covered aqueduct on wall on right + medusa head/myelencephalon medulla + 4th ventricle.
Location: Computer lab in library

5

What are microglia derived from?

mesoderm

6

Origin of CNS and PNS neurons

CNS neurons from neuroectoderm.
PNS neurons from neural crest

7

Neural tube area of codebook is basically...

neuroectoderm

8

What are ependymal cells derived from?

neuroectoderm

9

When do NTD's usually happen?

4th week

10

Caveat about spina bifida occulta

AFP won't be increased.

11

spina bifida occulta characteristics

1) dura intact
2) no herniation

12

What commonly herniates in meningomyelocele?

Cauda equina

13

Anencephaly findings

1) increased AFP
2) polyhydramnios (due to lack of swallowing center in brain).

14

Anencephaly association

maternal type I diabetes

15

Holoprosencephaly

♣ Coded character: /failure of left and right hemispheres to separate. 2 sharks at a table by window, hailing on one, other one sitting on a mound of hash/usually occurs during weeks 5-6. Erica emms is the waitress + has a clef lip + a Cyclops head/moderate form has cleft lip/palate, most severe form results in cyclopia.
♣ Location: right side of park burger

16

Chiari I malformation

o Code: kiara with a top hat on driving/Chiari I. /often diagnosed in adults and adolescents (less severe so less likely to present earlier). big mouth with inflamed tonsils on fairway + worm crawling out/Type I = significant herniation of cerebellar tonsils and vermis through foramen magnum. /more common but less severe than Chiari II. Nail through head + tape over mouth + antlers/presentation = headache and neck pain + lower brainstem symptoms (dysarthria + dysphagia + nystagmus). /can by asymptomatic.
o Location: Driving range at woodlands

17

arnold chiari malformation

♣ Coded character: huge mouth with tonsils hanging out + worm crawling out + medusa head on top/type II = tonsils + vermis + medulla herniate into the foramen magnum. Arnold Palmer: Roman aqueduct surrounding putting green/aqueductal stenosis. Arnold dancing around/mostly asymptomatic. Geiser of water coming out of his head + he’s on a stretcher (paralysis code) + huge sack hanging out of his lumbosacral region/presentation = hydrocephalus + lumbosacral meningomyelocele (this is what generates the pressure gradient and causes the herniation) + paralysis below level of defect. Siamese twin kiaras putting/Chiari II. He’s naked but wearing a cloak/syringomyelia is common.
♣ Location: Putting green at the woodlands

18

Enlargement of 4th ventricle...

Dandy-Walker syndrome

19

Dandy walker associations...

1) noncommunicating hydrocephalus
2) spina bifida

20

anterior white commissure part of...

Spinothalamic tract

21

syringomyelia causes

1) chiari malformations
2) trauma
3) tumors

22

Chiari 1 presentation

headaches + cerebellar symptoms

23

Most common location of syrinx

C8-T1

24

neuro loss with syringomyelia?

Bilateral loss of pain and temperature sensation with fine touch sensation preserved.

25

Tongue brachial arch origins

o Code: big tongue stuck ito ground with arch overhead. Hat on top + chicken nesting on top/anterior 2/3s of tongue is associated with pharyngeal arches 1 and 2. Hambone stuck into bottom/posterior 1/3 of tongue associated with pharyngeal arch 3.
o Location: patio outside St. Marks

26

Taste innervation of tongue

anterior - CN VII
posterior - IX, X (extreme posterior)

27

Pain innervation of tungue

anterior - V3
posterior - IX,X

28

hyoglossus action

retracts and depresses tognue

29

genioglossus action

protrudes tongue

30

syloglossus action

draws sides of tongue upward to create a trough for swallowing.

31

Motor innervation of tongue

1) CN XII to hyoglossus + genioglosus + sytloglossus
2) CN X to palatoglossus.

32

What does Nissl staining stain?

RER

33

What does Nissl staining pick up and not pick up?

1) cell bodies + dendrites
2) can't stain axon (No RER) or microglia

34

Wallerian degeneration

Any injury to axon.
1) degenerates distal to injury
2) axon retracts proximally

35

Astrocyte functions

1) physical support
2) repair
3) K+ metabolism
4) removal of excess neurotransmitter
5) BBB
6) glycogen fuel reserve buffer
7) reactive gliosis in response to neural injury

36

Why does GFAP a marker of?

astrocytes

37

Microglia relevance to HIV

When infected by HIV, they fuse to form multinucleate giant cells.

38

Microglia function

Phagocytic, scavenger cells. Activated in response to tissue damage.

39

Myelin affects on nerves

1) increase space constant
2) increase conduction velocity

40

space constant

AKA length constant. Distance electric potential will travel along a neurite via passive electrical conduction.

41

Schwann cells and myelination

Each schwann cell myelinated only 1 PNS axon

42

Significance of nodes of Ranvier?

High concentration of Na channels

43

Guillain-Barre injury

damaged Schwann cells

44

typical location of vestibular schwannoma

internal acoustic meatus

45

Oligodendroglia and number of axons myelinate

many (around 30)

46

White vs. grey matter

1) Grey matter contains numerous cell bodies and relatively few myelinated axons.
2) White matter contains mostly myelinated axons. Myelin is white.

47

Predominant glial cell type in white matter?

Oligodendroglia

48

Histologic appearance of oligodendroglia?

Fried eggs

49

What is damaged in leukodystrophies?

oligodendroglia

50

Sensory neuron fiber type in free nerve endings?

C fibers and AlphaDelta fibers

51

Where are free nerve endings?

All skin + epidermis + some viscera

52

C fiber characteristics?

Slow, unmyelinated

53

Alphadelta fiber characters?

Fast, myelinated

54

C and Alphadelta fibers sense?

Pain temperature

55

Difference in sensitivity between C and Alphadelta fibers?

1) Alphadelta are faster so sense quick shallow pain specific to one area.
2) C fibers are slow and respond to stronger intensities, so deeper and more spread out stimuli.

56

Meissner corpuscles characteristics

Large, myelinated fibers; adapt quickly

57

Meissner corpuscles expressed in...

Glabrous (hairless) skin

58

Meissner corpuscles functions

1) dynamic touch
2) fine/light touch
3) position sense

59

Pacinian corpuscles characteristics

1) large, myelinated
2) adapt quickly

60

Pacinian corpuscles expressed in

Deep skin layers, ligaments, joints

61

Pacinian corpuscles sense

Vibration + pressure

62

Merkel discs characteristics

1) large, myelinated
2) adapt quickly

63

Merkel discs expressed in...

Finger tips + superficial skin

64

Merkel discs sense

1) pressure
2) deep static touch (eg shapes, edges)
3) position sense

65

Ruffini corpuscles characteristics

1) Dendritic endings with capsule
2) adapt slowly

66

Ruffini corpuscles expressed in

Finger tips + joints

67

Ruffini corpuscles functons

1) pressure
2) slippage of objects along surface of skin
3) joint angle change

68

endo vs peri vs epineurium

1) Endoneurium surrounds single nerve fiber
2) Perineurium surrounds fascicle of nerve fibers
3) Epineurium is dense connective tissue surrounding entire nerve and contains fascicles and blood vessels.

69

perineurium function

permeability barrier

70

Where is the inflammatory infiltrate found in Guillain-Barre?

Endoneurium

71

What needs to be rejoined in microsurgery for limb reattachment?

Perineurium