Neuro VHA

Question 1

How do myelinated axons stain?

Answer 1

myelin does not stain well so they look white with large nucleus in middle

can look wavy

Question 1

What surrounds a bundle of axons?

Answer 1

perineurium

Question 2

What is structure of fibers in dorsal root ganglia?

Answer 2

pseudounipolar

Question 3

What is contained in the dorsal root ganglia?

Answer 3

sensory nerves

PNS nerves

Question 4

Connective tissue near axon bundle

Answer 4

perineurium

Question 5

What is the only location where psuedounipolar cells are found?

Answer 5

dorsal root ganglion

Question 6

What is an autonomic ganglion composed of?

Answer 6

cell bodies of motor neurons

Question 7

Are there neuronal cell bodies in the PNS? If yes, where?

Answer 7

not typically in periphery

can see neuronal cell bodies in the periphery if in a ganglion

Question 8

What does Nissl stain?

Answer 8

the RER

Question 9

What can you use to stain myelin?

Answer 9

Luxol fast blue

Question 10

Where do sensory signals pass through before reaching the spinal cord?

Answer 10

pass through dorsal root ganglion first

Question 11

Where are bipolar neurons found?

Answer 11

special senses, like smell

Question 12

What type of neurons are in CNS and autonomic ganglia?

Answer 12

multipolar

Question 13

afferent fibers

Answer 13

sensory

deliver information from PNS to CNS

Question 14

efferent fibers

Answer 14

motor

can cause voluntary (somatic) or involuntary (autonomic) muscle movements

Question 15

where is a 2 neuron pathway found?

Answer 15

autonomic efferent fibers

Question 16

Which cells myelinate and where?

Answer 16

COPS

CNS = oligodendrites

PNS = Schwann

Question 17

What does gray matter contain?

Answer 17

glial cells and neuronal cell bodies

Question 18

What does white matter contain?

Answer 18

glial cells and myelinated axons

Question 19

How can you detect MS by staining?

Answer 19

when you add Luxol blue stain to find myelin there are areas of no myelination

these are plaques and representative of MS

Question 20

How can you detect MS on MRI?

Answer 20

optic nerve is present, indicates optic neuritis

fingerlike plaques in the brain scan

Question 21

What are fingerlike plaques called on MS MRI?

Answer 21

Dawson finger

Question 22

When looking at a bundle of axons in the periphery, what are you actually seeing on stain?

Answer 22

actually seeing nuclei of surrounding glial cells

axon itself does not stain and neuronal cell bodies are not located in the periphery

Question 23

What are the general steps of peripheral reflexes?

Answer 23

1. relay signal to cell body in DRG
2. DRG synapes with interneuron in gray matter of spinal cord
3. interneuron synapes with cell body of motor neuron in gray matter
4. motor neuron sends message to pull hand away

Question 24

5 places where MRI is good to use

Answer 24

1) neuropsychiatric 2) musculoskeletal 3) cardiac 4) abdominopelvic 5) breast

Question 25

T1 / T2 in MRI

Answer 25

T1 is bright/white for fat T2 is bright/white for fat and water

Question 26

Difference in CSF on T1/T2 images

Answer 26

Since T2 is bright for water, CSF will be bright on T2 scan On T1 scan, CSF will be dark since not fat

Question 27

Why is bone always black on both T1 / T2?

Answer 27

contains no free protons so stays black

Question 28

TR in MRI

Answer 28

repetion time amount of time between successive pulse sequences applied to the same slice

Question 29

TE in MRI

Answer 29

time to echo time between the delivery of the RF pulse and the receipt of the echo signal

Question 30

diffusion

Answer 30

how far water molecules go through body can use for stroke when cells die, H2O rushes in (can see cells affected by stroke)

Question 31

FLAIR in MRI

Answer 31

Fluid attenuated inversion recovery special type of inversion that can remove CSF

Question 32

When is FLAIR useful?

Answer 32

remove CSF in MS brain scans allows us to see the Dawson finger's better

Question 33

What is fat suppression useful?

Answer 33

can see organs better ex: might suppress fat in eyes to potentially see optic nerve better

Question 34

gadolinium

Answer 34

main type of contrast used in MRI works by changing the relaxitivity of nearby water molecules shows blood flow and damage to blood barriers

Question 35

Cancerous tissue and gadolinium

Answer 35

normally appears brighter when gadolinium is used since cancer is vascular and has high uptake can be used to find hidden tumors in T1 scans!