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Ocular Phys > B10 > Flashcards

B10 Flashcards

1
Q

The pupil that is seen is actually a _____ image of the ____ pupil

A

Magnified virtual image of the real object pupil

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2
Q

Name the 7 functions of the iris

A
  • improve visual clarity (regulates optical aberrations
  • attraction/mate selection
  • non verbal communication
  • reduce glare
  • control illumination
  • prevent dazzling
  • increase the depth of focus
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3
Q

The iris separates the

A

Anterior and posterior chambers of the eye

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4
Q

The iris is surrounded by what fluid?

A

Aqueous

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5
Q

T/f: the iris is the most anterior portion of the uveal tract

A

True

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6
Q

The iris rests lightly upon the ___

A

Lens

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7
Q

What is the average diameter of the iris?

A

12mm

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8
Q

The pupil center is slightly __ and ___ to the iris center

A

Slightly nasal and inferior

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9
Q

An abnormally decentered pupil

A

Ectopic

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10
Q

What does irregular or ectopic pupils do to optical quality

A

They degrade it

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11
Q

The pupillary margin rests on the ___ surface of the lens

A

Anterior

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12
Q

How does aqueous humor flow

A

It flows from the posterior–>anterior through the pupil

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13
Q

T/F: Temporal iris in humans broader than nasal iris

A

True

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14
Q

The posterior portion of the iris is derived from?

A

Neuroectoderm/neuroepithelium

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15
Q

The dilator muscle is derived from the

A

Neuroepithelium

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16
Q

The sphincter muscle is derived from the

A

Neuroepithelium

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17
Q

The posterior pigmented epithelium is derived from the

A

Neuroepithelium

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18
Q

The anterior portion of the iris is derived from

A

Mesoderm

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19
Q

The iris stroma is derived from

A

Mesoderm

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20
Q

The iris vessels is derived from

A

Mesoderm

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21
Q

The iris nerves are derived from

A

Mesoderm

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22
Q

The chromatophores are derived from

A

Mesoderm

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23
Q

What are the 4 layers of the iris?

A
  • anterior border layer
  • stroma and sphincter muscle
  • anterior epithelium and dilator muscle
  • posterior epithelium
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24
Q

What layer contains both mesoderm and ectoderm

A

Stroma and sphincter muscle

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25
Q

The reduction in optical aberrations and depth of focus is optimal at

A

2mm or less

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26
Q

What are the only elements in the iris that is capable of initiating movement

A

Iris muscles

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27
Q

What occurs in miosis (constriction if pupils)

A

the pupillary portion of iris gathers into pleats while the ciliary portion smooths out.

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28
Q

What occurs in mydriasis (dilation)

A

the stroma in the pupillary zone pulls flat while

contraction furrows appear in the ciliary area.

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29
Q

T/F: blow flow is impeded by wither miosis or mydriasis

A

False. It is not impeded

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30
Q

T/F: in the past, it was believed that the stroma and blood vessels were responsible for iris movements, via elastic expansion, changes in hydration, and/or engorgement.

A

True

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31
Q

T/F: the stroma and iris vessels are elastic

A

False. They are not elastic

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32
Q

is a loose but orderly meshwork of collagen fibers with aqueous fluid and scissor like angles for folding

A

Stroma

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33
Q

Thin-walled layer of endothelium with an outer

covering of collagen fibrils.

A

Iris vessels

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34
Q

The thickest portion of the iris

A

Stroma

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35
Q

What are the 4 functions of the stroma

A
  • provides an anchor for structures
  • protects the nerves and vessels from stretching and kinking
  • adapts to constant movement
  • folds and unfolds with minimal resistance to minimize energy expenditure
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36
Q

The stroma provides an anchor for what 4 structures?

A
  • sphincter muscle
  • dilator-posterior-epithelial plate
  • iris nerve
  • iris vessels
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37
Q

Structure that is more densely than deeper stroma

A

Anterior border layer

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38
Q

Dark brown spots that are compact masses of rounded cells filled with melanin

A

Nevi

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39
Q

T/F: the anterior border layer is more solid and dense with more layers in darkly pigmented eyes.

A

True

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40
Q

What kind of cells does the ABL have

A

Fibroblasts interlaced with melanocytes

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41
Q

T/F: In the ABL the iris is porous (no anterior limiting layer)

A

True

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42
Q

What gives us a blue iris

A

Light scatter in uniform space across stromal tissue

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43
Q

Why do most newborns start out with blue eyes then turn dark?

A

Because they haven’t developed pigment yet

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44
Q

What causes dark irises?

A

Development of anterior stromal melanocytes and production of pigment

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45
Q

Blood flow of the iris is derived from

A

ophthalmic artery from two long posterior ciliary arteries and anterior ciliary arteries.

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46
Q

The anterior ciliary arteries run along the

A

Rectus muscles

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47
Q

T/F: the iris doe not bleed when its cut

A

True

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48
Q

There are 2 anterior ciliary arteries in each rectus muscles except for

A

Lateral rectus (it only has 1)

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49
Q

Allows for little distension and folding of vessels during constant movement of iris

A

Perivascular collagen sheaths

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50
Q

T/F: Perivascular collagen sheaths are unique to iris vessels

A

True

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51
Q

T/F” Humans react to light stimulation of the retina rather than the iris.

A

True

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52
Q

Light reflex is an important test to discover the integrity of the

A
  • retina
  • optic nerves
  • chiasm
  • optic tracts
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53
Q

The entire stimulus response function resembles a ___curve

A

S curve

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54
Q

The latency time becomes ____ with dimmer light stimuli

A

More prolonged

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55
Q

In scotopic and photopic conditions, the pupil_____with variability in light

A

Doesnt really change all that much

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56
Q

In mesopic conditions, the pupil_____with variability in light

A

Changes a lot

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57
Q

In the dark adapted state, the threshold light of intensity needed to produce a pupil contraction becomes ___ as rods are brought into play

A

Less

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58
Q

T/F: Rods in the dark adapted state do not produce as much increase in pupil contraction in response to increases in stimulus intensity

A

True

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59
Q

In dark-adapted eyes, pupillary reactions occur at intensities

A

Below photopic range

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60
Q

In dark adapted eyes the parafovea and peripheral are ____ sensitive than the fovea

A

More

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61
Q

In normal light adapted eyes, pupillary threshold is

A

Much higher

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62
Q

In normal light adapted eyes, the fovea is ___reactive than the periphery

A

More

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63
Q

T/F: the pupil has a max speed to contract

A

True. Not matter the intensity of light the pupil will contract at the same speed

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64
Q

What is the max speed of pupil contraction?

A

4 Hz

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65
Q

T/F: The pupil has to be able to see a stimulus long enough for it to react

A

True

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66
Q

With longer duration of a stimulus, the pupil contracts___, there is a ___latency time, and the contraction lasts ___

A
  • contracts more
  • shorter latency times
  • contraction lasts longer
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67
Q

The pupil is more constricted when the light covers a ____ area and when light is ____bright

A

Covers a greater area and light is equally bright

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68
Q

T/F: Pupils sums afferent impulses regardless of spatial distribution, both rods and cones.

A

True

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69
Q

Under dark adaptation, the fovea shows ___ sensitivity compared to surrounding retinal areas because of the lack of rods

A

Decreased

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70
Q

In mesopic and photopic adaptations the pupil responds greatest in the ___ field

A

Central

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71
Q

T/F: the temporal field response is usually greater than the nasal field response

A

True

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72
Q

The peak sensitivity under photopic conditions is

A

Green 550

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73
Q

The peak sensitivity under scotopic conditions is

A

Blue

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74
Q

The greater the spatial frequency, the ___ the pupil contracts

A

Less

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75
Q

20/20 has a ___ spatial frequency

A

High

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76
Q

T/F: The pupil responds to motion even when the light level stays the same

A

True

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77
Q

Some people think that myopes have ___ pupils and hyperopes have ___ pupils

A

Myopes: larger pupils
Hyperopes: smaller pupils

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78
Q

Larger pupils can result in what 2 things

A
  • Image degradation

- glare

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79
Q

If the pupils are too small (<2mm) what 2 things can effect visual performance

A
  • diffraction limited

- reduced illumination

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80
Q

What is the optimal pupil size?

A

2mm

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81
Q

Does pupil size increase of decrease with age?

A

Decreases

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82
Q

The pupil diameter can vary between?

A

2-8 mm

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83
Q

What is the near vision triad?

A

Convergence, miosis, and accommodation

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84
Q

What is the 3rd nerve nucleus?

A

Eddinger-Westphal

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85
Q

Amplitude for young people is ___ to contraction from bright light

A

Equal

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86
Q

Is iris sphincter and dilator muscle is derived from

A

Neuroectoderm

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87
Q

The iris sphincter is predominately innervated by

A

The parasympathetic system

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88
Q

The iris dilator is predominately innervated by?

A

The sympathetic system

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89
Q

T/F: the sphincter and dilator muscle are equally strong

A

True

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90
Q

When are the pupils smaller?

A

During sleep and death

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91
Q

When are the pupils bigger?

A

During waking hours and when frightened

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92
Q

What 3 things can elicit a pupillary dilation?

A
  • sensory
  • emotion
  • mental
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93
Q

If something is less arousing how will this effect a pupillary reaction?

A

There will be less of a pupillary response

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94
Q

If you are infuriated, will you have a greater or lesser pupillary reaction?

A

Greater

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95
Q

What are some findings of pupil size in adults

A
  • they can still respond fully to mydriatic drugs
  • pupils are still round and smooth
  • light reflex remain brisk
  • reduction is size is a linear process
  • no change in thickness of dilator muscle with age
  • decreasing pupil size begin in healthy eyes with strong levels or accommodation and brisk reactive pupils
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96
Q

If someone has horners syndrome what happens to the pupil when you put cocaine in their eye?

A

The horners pupil dilates less than the normal pupil

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97
Q

What does cocaine do to the eye?

A

blocks the reuptake of post-ganglionic norepi

resulting in the dilation of a normal pupil from retention of norepi in the synapse.

98
Q

What can high levels of infrared do to the eye?

A

It can burn any ocular structure and have very deep penetration

99
Q

What layer of the iris absorbs heat?

A

The black pigment of the posterior iris layer

100
Q

When stimulated directly by heat, what happens to the iris sphincter?

A

It contracts

101
Q

If the iris ensues, what may occur?

A

Long-lasting miosis

102
Q

T/F: the ciliary body contains the minor arterial circle of the iris

A

False

103
Q

What is the most posterior structure when looking doing gonio?

A

Ciliary body

104
Q

What is the most anterior structure when doing gonio?

A

Schwalbes line

105
Q

Name the order from anterior to posterior when doing gonio

A

Schwalbes line–> trabecular meshwork –> scleral spur –> ciliary body

106
Q

Name the 4 functions of the ciliary body?

A
  • accommodation
  • aqueous production
  • aqueous outflow
  • indirectly causes iris contraction
107
Q

What does aqueous production do?

A

Supplies nutrients to the lens and cornea

108
Q

What does aqueous outflow do?

A
  • Maintains IOP

- removes waste products

109
Q

What are the 3 main process to produce/secretary aqueous humor?

A
  • diffusion
  • ultrafiltration
  • active secretion
110
Q

The stroma within the ciliary processes contains a dense network of ____ capillaries, and the number and shape of the processes provides a large ____ for secretion into the posterior chamber.

A
  • fenestrated capillaries

- large surface area

111
Q

Active secretion accounts for ___ of aqueous production

A

80-90%

112
Q

What is the most significant factor in aqueous production?

A

Active secretion

113
Q

What facilitates water movement

A
  • coordination of ion pumps, channels
  • cotransporters in the 2 epithelial
  • aquaporins
114
Q

What primarily drives secretion in the posterior chamber?

A

Movement of Na+ and Cl-

115
Q

What has an indirect role in moderating the Cl flux

A

Bicarbonate

116
Q

What is the rate of aqueous production?

A

2.5 ul per minute

117
Q

This substance is a metabolic waste produce of glycolysis of the lens and cornea and is in high concentrations in the aqueous

A

Lactate

118
Q

Ascorbate concentration is ___ higher in the aqueous than in blood plasma

A

20x

119
Q

If aqueous produced more during the day or night?

A

Day. Decreased 50% at night

120
Q

T/F: Dilating and constricting blood vessels can influence aqueous blood vessels by increasing and decreasing blood volume.

A

True

121
Q

Diameter of zonular fibers

A

70-80mm

122
Q

Elastic fibers that stabilize the lens and allows fluid to flow from the posterior chamber to the vitreous. And attaches to the lens

A

Zonular fibers

123
Q

When is accommodation lost?

A

Age 50

124
Q

Describe accommodation

A

Contraction of the longitudinal fibers of the ciliary muscle pulls the choroid forward, and contraction of the circular fibers draws the CB closer to the lens, decreasing the diameter of the ring formed by the CB. This releases tension on the zonule fibers and allows the lens capsule
to adopt a more spherical shape.

125
Q

During accommodation the lens ____ ,the anterior surface curve ____, zonular fibers ____, the lens capsules becomes a more ___shape, and _____ refractive power

A 
The lens thickens 
The anterior curve increases 
Zonular fibers relax
Lens capsule becomes more spherical shape
Increases refractive power
126
Q

When looking at a distance, the ciliary muscle is ___ and the zonular fibers are ___

A

The ciliary muscle is relaxed

The zonules are pullin on the lens capsule

127
Q

Pilocarpine cases ciliary muscle ____

A

Contraction

128
Q

Does accommodative amplitude decrease or increase with age

A

Decrease

129
Q

What stimulates miosis

A

Accommodation and convergence

130
Q

Subjective measurements of accommodation rely on

A

Perception of clarity

131
Q

Objective measurements of accommodation can be obtained with an

A

Autorefractor or aberrometer

132
Q

T/F: dynamic measurements are better than static measurements

A

True

133
Q

What really effects presbyopic eye movement?

A

The lens becoming thicker and stiffer

134
Q

T/F: reduced near vision is caused by significant reduction in strength of ciliary muscle

A

False. It is not caused by it

135
Q

What are some structural changes in the aging eye that could lead to reduced contractile force?

A
  • thickening of tendons
  • reduced muscle mass
  • increased connective tissue
136
Q

T/F: Measurements of contractile strength of ciliary muscle strips with stimulation show no reduction with increasing age.

A

True

137
Q

In presbyopes are there changes in M receptor numbers, binding affinity, or ACh activity?

A

No

138
Q

Loss of the ability to accommodate

A

Presbyopia

139
Q

Ciliary muscle contractive power ___ up until age that

presbyopia manifests.

A

Increases

140
Q

Are there changes in zonular length with age?

A

No

141
Q

What is the limiting factor for accommodation

A

The movement and shape of the lens

142
Q

Why can ciliary muscle contraction change the configuration of the TM?

And what does this do?

A

Because some of the longitudinal fibers are attached to the TM sheets

Facilitates aqueous movement through the anterior chamber angle structures

143
Q

What is the max reductions of IOP when dealing with accommodation?

A

2.38mmHg

144
Q

The ciliary muscle is derived from

A

Mesoderm

145
Q

Describe the Tyndall phenomenon

A
  • When breakdown of blood-aqueous barrier occurs, cells and flare become visible.
  • Often immune factors, leucocytes.
  • Usually whitish
  • Can form hypopyon
146
Q

What is hyphema?

A

-Trauma to head or injury such as whiplash can tear/ break the iris
-This can break the iris blood vessels entering from the major circle of
the iris
-Blood settles inferiorly.

147
Q

A clear, colorless fluid that fills the anterior

and posterior chamber of the eye

A

Aqueous Humor

148
Q

What are the 4 functions of the AH?

A

-Supplies nutrients and oxygen to and remove metabolic wastes from the anterior intraocular tissues such as cornea, lens and TM
-Inflates the eye globe and creates an IOP for normal optical functioning of the eye
-Transports ascorbic acid(AA) into anterior segment where it
serves as an antioxidative agent
-Facilitates the local immune responses during inflammation and
infection

149
Q

What is the primary site of AH formation?

A

Pars plicata

150
Q

Which layer of the CE is necessary for AH formation?

A

Non-pigmented epithelium

151
Q

What is the major mechanism of solutes across CE?

A

Active transport

152
Q

What drugs reduce aqueous humor formation?

A

CAI and alpha 2 agonists

153
Q

Which one has a higher concentration of protein? (Blood plasma or aqueous humor)

A

Blood plasma

154
Q

Which one has a higher concentration of ascorbic acid? (Blood plasma or aqueous humor)

A

Aqueous humor

155
Q

Beta 2 agonist ___aqueous humor formation

A

Increases

156
Q

Is AH average rate of formation greater or less during the daytime?

A

Greater (2.75 ul/min)

157
Q

What is the pathway (5 steps) of the blood to the AH?

A

1.) Blood flow–>vascular bed of ciliary stroma
2.) Loading of solute from the ciliary stroma blood into the PE cells
3.) Translocation of solute through the gap junction into the NPE
cells
4.) Exclusion of solute from the NPE cells to the posterior
chamber (driven by an electrochemical gradient and/or by
active transport)
5.) The osmotic gradient established by the solutes facilitates the
passive flow of water into the posterior chamber by osmosis

158
Q

What are the 3 mechanisms of solutes across the CF?

A
  • Diffusion
  • ultrafiltration
  • active transport
159
Q

Defined as the passive movement of solutes across the CE in response to a concentration gradient

A

Diffusion

160
Q

defined as the passive movement of water and water soluble substances across cell membranes as a result of the hydrostatic and oncotic pressure between the ciliary stroma and the AH

A

Ultrafiltration

161
Q

an energy-consuming process involving the movement of solutes across the CE against their concentrations gradients

A

Active transport

162
Q

Will people who smoke marijuana have increased or decreased IOP?

What causes this?

A

Decreased IOP

9-THC

163
Q

Is IOP constant throughout the day?

A

No

164
Q

Why don’t we want a lot of protein in the AH?

A

Because we want to keep transparency

165
Q

What is the major part of the blood aqueous barrier?

A

Tight junctions between NPCE cells

166
Q

What 2 things are allowed to pass to the posterior chamber?

A

Ions and water

167
Q

What is a part of the primary vitreous

A

Hyaloid artery

168
Q

What are the 3 conditions with remnants of the hyaloid artery?

A
  • cloquets canal
  • bergmeisters papillae
  • mittendorfs dot
169
Q

What is the outermost zone of the vitreous?

A

Vitreous cortex also called hyaloid surface

170
Q

What is the center zone of the vitreous called?

A

Cloquets Canal (hyaloid canal)

171
Q

What is the intermediate zone of the vitreous?

A

Inner to the cortex and surrounds the center canal

172
Q

Where does AH come from?

A

Blood plasma

173
Q

Barrier to the movement of intermediate- and high-

molecular weight substances such as protein.

A

Blood aqueous barrier

174
Q

Barrier protecting the eye from entry of toxic substances and maintaining the homeostatic control

A

Blood aqueous barrier

175
Q

Barrier that explains why drugs administered orally
or IV can hardly reach therapeutic levels in
intraocular tissue

A

Blood aqueous barrier

176
Q

Tight junctions are present in the ____ ciliary epithelium

A

Non-pigmented ciliary epithelium (NPCE)

177
Q

Other than NPCE where are tight junctions also present?

A
  • in the iridial vascular endothelium

- between the iris epithelial

178
Q

Endothelial of the inner wall of _____ are tight joined to prevent retrograde movement of solutes and fluid from the canal lumen into the AC

A

Schlemms canal

179
Q

Tight junctions between NPCE cells constitute an effective barrier to intermediate and high molecular weight substances such as ____

A

proteins

180
Q

What happens to the aqueous when there is a breakdown of the BAB?

And what cells may also be present?

A

Aqueous becomes cloudy due to leakage of plasma proteins into the posterior chamber (PC) and anterior chamber (AC).

Inflammatory cells may also be present.

181
Q

In anterior uveitis what 2 things will you see?

A

Cells and flares (proteins)

182
Q

Breakdown of the BAB can cause what 2 eye conditions?

A
  • Anterior uveitis

- hyphema

183
Q

Blood in the anterior segment due to trauma

A

Hyphema

184
Q

What are 4 ocular injuries that causes or is caused by BAB breakdown

A
  • Surgical and non-surgical traumas
  • —hyphema
  • Intraocular inflammation (such as uveitis)
  • Vascular and systemic disorders (such as diabetes)
  • Intraocular tumor
185
Q

is usually defined as an IOP of 5 mm Hg or less (extremely low pressures)

A

Ocular hypotony

186
Q

When there is ocular inflammation what 2 things are releases?

A
  • cytokines

- growth factors

187
Q

Clear gel which occupies the posterior compartment of the eye.

A

Vitreous

188
Q

The vitreous is located between the ___ and the ___

A

Retina and lens

189
Q

The vitreous occupies ___ of the volume of the eye

A

80%

190
Q

Light initially entering the eye through the
cornea, pupil and lens, is transmitted through the
____ to the ____

A

Vitreous –> retina

191
Q

3-4 gestational stage of the vitreous

A

Primary vitreous

192
Q

6th gestational week of vitreous

A

Secondary vitreous

193
Q

Zonular fibers are in the ___ vitreous

A

Tertiary

194
Q

Is secreted by NPCE of pars plana and persists in the

adult as the suspensory ligament of the lens

A

Zonular fibers (tertiary vitreous)

195
Q

Optic cup filed by a system of fibrillar material, presumably secreted by embryonic retina cells is during what stage of vitreous development?

A

Primary vitreous

196
Q

VEGF released by lens induces vasculogenesis; Hyaloid artery penetration is a part of what vitreous developmental stage?

A

Primary vitreous

197
Q

Vitreous stage where Anti-angiogenesis factor present, Hyaloid vessels retract, Vitreous gel body formed

A

Secondary vitreous

198
Q

arises from the center of the optic disc, consists of a small tuft of fibrous tissue and represents a remnant of the fetal hyaloid artery.

A

Bergmeister’s papillae

199
Q

small, circular opacity on the posterior lens capsule, classically nasal in location, which represents the anterior attachment of the hyaloid artery.

A

Mitterndorfs dot

200
Q

a tubular structure containing remnants of the primary vitreous, located between the posterior aspect of the lens and the retina in the vicinity of the optic disk

A

Cloquets canal (hyaloid canal)

201
Q

The pigmented and nonpigmented CE are connected by

A

Gap junctions

Apex to apex

202
Q

The middle layer of the eye

A

Uvea

203
Q

What are the 3 regions of the uvea?

A
  • iris
  • CB
  • choroid
204
Q

The choriod extends from the ___ to the ___

A

Ora serrata to the optic nerve

205
Q

The choroid is located between the ___ and the ___

A

Sclera and retina

206
Q

Layer of the choroid that is thin, pigmented, connective tissue

A

Suprachoroid

207
Q

Pigmented, vascularized, loose connective tissue that contains melanocytes, fibroblasts, macrophages, lymphocytes, mast cells

A

Large and medium vessels

208
Q

A later of the choroid that is a single layer of fenestrated capillaries

A

Choriocapillaris

209
Q

This layer of the choroid fuses with the retina multilaminated sheet

A

Bruchs membrane

210
Q

____choriod absorbs excess light

A

Darkly pigmented

211
Q

Provides nutrients to and remove the waste products from outer retina

A

Vascular choroid

212
Q

Sole blood supply to the fovea

A

Choriocapillaries

213
Q

Provides a pathway for the posterior vessels that supply the anterior segment

A

Suprachoroidal space

214
Q

A branch of the ophthalmic artery

A

Ciliary artery

215
Q

What are the 2 branches of the ciliary artery

A

Short posterior ciliary artery and long posterior ciliary arteries

216
Q

Long ciliary nerves carries ___ and ___ fibers

A

Sensory and sympathetic fibers

217
Q

Short ciliary nerves carry ___ and ___fibers

A

Sympathetic and parasympathetic

218
Q

Provides a pathway for the nerves that supply the anterior segment

A

Suprachoroidal space of choroid

219
Q

If someone has a hyperopic defocus the choroid will be ___ and the growth is ______

A

Thin choroid and growth increased

220
Q

If someone has a myopic defocus the choroid will be ___ and the growth is ______

A

Thick choroid and growth decreased

221
Q

The choroid can ___ modulates its thickness, varying the position of the retina and the state of focus of the eye

A

Rapidly

222
Q

What are the 4 functions of the choroid?

A
  • Provide nutrients and remove the waste products from outer retina
  • Passage of nerves and vessels
  • Absorption of excess light
  • Regulate emmetropization (study in chicken)
223
Q

What are the 3 changes in the iris?

A
  • loss of pigmentation
  • dilator muscle becomes atrophic
  • sphincter muscle becomes sclerotic
224
Q

What are the 2 aging changes in the ciliary body

A
  • elasticity decreased due to the amount of connective tissue increased within the layer of the CB
  • formation of aqeuous humor decreases with aging
225
Q

What are the 3 aging changes in the choroid?

A
  • choriocapillaries decrease in density and diameter–>choroidal blood flow decreases
  • bruchs membrane increases in thickness
  • various substance and particles accumulates in bruchs membrane
226
Q

Nutrients from the choriocapillaries and waste product from the retina pass through what structure?

A

Bruchs membrane

227
Q

Name the 5 layers of the bruchs membrane

A
  1. ) interrupted basement membrane
  2. ) outer collagenous zone
  3. ) elastic layer
  4. ) inner collagenous zone
  5. ) basement membrane of RPE cells
228
Q

Calcification and the yellow deposits in the inner collagenous layer of Bruch’s membrane. Made of the remaining damaged cells (called lipofuscin) from the oxidative stress.

A

Drusen

229
Q

yellow-brown pigment granules composed of lipid-containing residues form oxidative stress

A

Lipofuscin

230
Q

Does the accumulation of drusen make Bruchs hydrophobic or hydrophilic?

A

Hydrophobic

231
Q

T/F: the accumulate of drusen inhibits the passage of metabolites

A

True

232
Q

Accumulation of water between RPE and bruchs membrane causes _____

A

Detachment

233
Q

Stage of ARMD where the choroid still functions

A

Dry ARMD

234
Q

What layer of the choroid is multilaminated sheet and fuses with RPE?

A

Bruchs membrane

235
Q

What provides blood to the fovea region?

A

Choriocapillaries

236
Q

What part of the retina receives blood supply from choroid?

A

Outer retina

237
Q

Which layer of the choroid proves a pathway for the vessels and nerves that supply the anterior segment?

A

Suprachoroidal space

238
Q

Which layer of Bruchs membrane does drusen deposit?

A

Inner collagenous zone

239
Q

Bruchs membrane thickness ___ with aging

A

Increases

240
Q

With pupil constriction you have a ____depth of field

A

Larger

241
Q

Low concentration of proteins in aqueous helps prevent ___

A

Light scatter

242
Q

Are there large amounts of protein in the aqueous?

A

No

Ocular Phys (6 decks)

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