Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ocular Block 7 > Retinal Topography And Vasculature > Flashcards

Retinal Topography And Vasculature Flashcards

1
Q

What is the retinas job

A

Innermost part of eye that does transduction and sends signal to brain

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

What is the retina the window into

A

The CNS and cardiovascular system

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

What happens in the retina

A
  • light energy is transformed into a neural signal (phototransduction)
  • signal is modified within the retina
  • contains the first three cells of the visual pathway: photoreceptors (1st), bipolar cells (2nd), and ganglion cells (3rd)
  • interneurons
  • neuroglia cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What must happen for light to reach the 1st order neuron

A

Light must pass through all layers of the retina to reach the 1st order neuron wher it is converted into neural signal by the process of phototransduction. The signal is modified by the 2nd and 3rd order neurons and sent to the brain

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

How many layers of the retina

A

10

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

What are the inner 9 layers collectively referred to as

A

The sensory or neural retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the 10th retinal layer

A

RPE

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

What are some cell types located within the retina

A

Many

-photoreceptors, horizontal cells, bipolar cells, amacrine cells, interplexiform cells, ganglion cells, and muller cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Are all regions of the retina the same

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the outer layers of the retina

A

Photoreceptor layer
External limiting membrane
Outer nuclear layer
Outer plexiform layer

All dealing with the photoreceptors

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

What is in the photoreceptor layer

A
  • rod outer segment
  • rod inner segment
  • cone outer segment
  • cone inner segment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is within the outer nuclear layer

A

Row of cone nuclei

Multiple rows of rod nuclei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is within the outer plexiform layer

A

Contains rod spherules and cone pedicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What do photoreceptors span

A

Outer retina (photoreceptor layer, external liming membrane, outer nuclear layer, and outer plexiform layer)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Role of photoreceptors

A

Absorb light photons and convert them into an electrochemical event (nerve signal) through the process of phototransduction.

Rods and cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How many cones

A

5-6mill

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What percentage of cones are in the fovea

A

10%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do cones detect

A

Bright illumination (photopic) and color

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

What are the 3 types of cones

A 
S cones (blue, 420)
M cones (green 531)
L cones (red 588)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the only photoreceptor in the fovea

A

Cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What type of cone is NOT in the center of the fovea

A

S cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How many rods

A

92-120 mill

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What do rods detect

A

Dim vision (scotopic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What do rods contain

A

Photopgiment, rhodopsin, which is located in the disc membrane

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

Peak density of rods

A

In a ring 4.5mm outside the fovea

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

Are there rods in the fovea

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Blind spot

A

ONH
Nasal
20 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Horizontal cells

A

Lateral processes between the cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the second cell in the chain of phototransudction

A

Bipolar cells

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

What do amacrine cells do

A

Processing

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

What do muller cells do in the retina

A

They are the radial glial cells of the retina

Maintain structural support/buffering environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Where are there astrocytes in the retina

A

RNFL around blood vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What does glaucaom kill

A 
Ganglion cells (3rd one) 
Stem cells wont work here
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Retinitis pigmentosa affects what

A

Photoreceptors

Stem cells could work here

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Retinal thickness

A

80 microns to 320

36
Q

Fovea retinal thickness

A

150-200

37
Q

What is the thinnest part of the retina

A

Ora serrata

80 microns

38
Q

Where is the ora serrata more serrated

A

Nasally

39
Q

Where is the ora serrata more smooth

A

Temporally

40
Q

What is there a dense population of in the central retina

A

Cones

41
Q

What is the central retina designed for

A

Color vision and fine detail discrimination

42
Q

What is there a dense population of in the peripheral retina

A

Rods

43
Q

What is the peripheral retina designed for

A

Night vision and motion detection

44
Q

How big is macula

A

5.5mm to 6mm diamter

45
Q

What is the only area of the retina that contains more than 1 layer of retinal ganglion cells

A

Macula

46
Q

What is there high levels of in the macula

A

Carotenoids

47
Q

What are the names ofhte parts of the macula from inside out

A 
Umbo
Foveola
Foveal avascular zone 
fovea 
Parafovea 
Perifovea 
Macula
48
Q

What causes the foveal light reflex

A

Umbo

49
Q

Central depression of macula that is 1.5mm in diamter

A

Fovea

50
Q

Walls of fovea

A

Walls slope giving rise to light reflex known as foveal light reflex

51
Q

What photoreceptors are in the fovea

A

Cones only

52
Q

How are the axons of cones oriented in the fovea

A

Obliquely in the outer plexiform layer of the fovea (henle fibers)

53
Q

How is the inner retinal layers displaced in the fovea

A

Laterally

54
Q

Central 350 microns of the fovea

A

Foveola

55
Q

Dense packing of cones makes them appear rod like in structure in this area

A

Foveola

56
Q

What is the thinnest region of the fovea

A

Foveola

57
Q

Cone inner fibers that are oriented obliquely within the fovea are called ________

A

Henle fibers

Thus, the OPL in the fovea is often referred to as Henke’s fiber layer

58
Q

What is Henles fiber layer

A

Outer plexiform layer obliquely displaced in the fovea

59
Q

Extend 0.5mm from the foveal rim

A

Parafovea

60
Q

Highes accumultion of bipolar and retinal ganglion cells

A

Parafovea

61
Q

Rod photoreceptors reach their peak density here

A

Parafovea

62
Q

1.5mm from the parafoveal rim

A

Perifovea

63
Q

Axons of Henles fiber layer resume their vertical orientation here

A

Perifovea

64
Q

Peripheral retina

A

Rod dominated region of central retina

Terminates at the ora serrata

65
Q

What is the peripheral termination of the retina

A

Ora serrata

66
Q

Outer Retinal vasculature

A

Choroid (for photoreceptors)

67
Q

Vasculature for the inner retina

A

Retinal vessels (central retinal vasculature)

68
Q

Is there an overlap between the choroidal blood supply and the central retina lblood supply

A

No

69
Q

Cilioretinal artery

A

20% of population has this. It is collateral blood supply to the macula

70
Q

Which is more nasal, central retinal artery or vein

A

Artery

71
Q

Which is more temporal, central retinal artery or vein

A

Vein

72
Q

Which is bigger, central retina artery, or vein

A

Vein

2:3

73
Q

When does the central retinal artery loose its elastic tunic

A

Upon entering the eye

This distinguishes it from the muscular arteries in other parts of body

74
Q

What is the tunica elasticum of the central retinal artery replaced with when it enters the eye

A

Prominent tunica media composed of smooth muscle

75
Q

Control of retinal vasomotor tone is

A

Auto regulated

76
Q

Control of choroidal vasomotor tone is

A

Neuroregulated

77
Q

What does the smooth muscle in the tunica media respond to in the central retinal artery

A

IOP and systems pressure, and metabolic waste levels

78
Q

Pericytes in the retinal caps

A

Helps blood flow

79
Q

Pericytes in DM

A

Increased blood sugar converts glucose to OH which kills pericytes and weakens others, causing fluid to leak into the eye through there

80
Q

Loss of pericytes and endothelial cells from retinal caps in DM patients can lead to

A

Microaneurysms, hemorrhages, exudates, and fluid in the macular region

81
Q

What are the two layers of the retinal cap plexus

A

Deep cap plexus

Supercficial cap plexus

82
Q

Round hemorrhages

A

Deep

83
Q

Flame shaped hemorrhage

A

Superficial cap plexus

RNFL

84
Q

What kind of shift do you get with macular edema

A

Hyperopic shift

85
Q

Which branch is more likely to be occluded in bran retinal vein occlusion

A

Superior, just because there are more of them

86
Q

Neovascularization

A

Will be leaky. Any vessels developed after Birth will be leaky

87
Q

When is it a good time to have a cilioretinal artery

A

Central retinal artery occlusion

Ocular Block 7 (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions