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OCULAR PHYSIOLOGY > Cornea 2 > Flashcards

Cornea 2 Flashcards

1
Q

What is the function of tight junctions?

A

barrier( but not as good as epithelial)

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2
Q

T/F Tight junctions do completly encircle the cells like zonula occludena

A

F Do not completely encircle the cells like zonula occludens

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3
Q

T/F Tight junctions are also called macula occludens

A

T

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4
Q

T/F Tight juncitons are a leaky barrier between aqueous and stroma in the endothelial cell-cell adhesion

A

T

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5
Q

What is the function of gap juncitons?

A

For intercellular communication

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6
Q

Where are gap junctions found?

A

lateral membranes

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7
Q

T/F Gap junctions do contribute to the endothelial barrier

A

F. Gap juncitons do not contribute to the endothelial barrier

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8
Q

What type of junctions interconnected endothelial cells?

A

tight junctions and gap junctions

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9
Q

What is the difference between macula occludens and zonula occludens?

A

Macula occludens do not completely encircle the cells

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10
Q

T/F gap junctions can also be found in the apicolateral membranes not just the lateral membranes

A

T

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11
Q

Two factors contribute to the prevention of stromal swelling what are they?

A
  1. barrier funciton of the endothelium

2. pump funciton of the endothelium

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12
Q 
water is maintined at \_\_%
A)88%
B)68%
C)78%
D)80%
A

78

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13
Q

T/F The barrier of the endothelium is incomplete compared with the epithelial barrier

T/F If the corneal endothelium is disrupted the stroma will swell up less, compared to if the metabolic pump was disrupted

A

T

F MORE

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14
Q 
With the endothelium disrupted the corne's stroma swells at \_\_\_\_\_ um/hr
A)50
B)127
C)107
D)100
A

127

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15
Q

With just the metabolic pump disrupted, the cornea’s stroma swells at __ um/hr

A)13
B)20
C)33
D)40

A

33

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16
Q

T/F normal leakage of Fluid is vital in the stroma of the cornea

A

T

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17
Q

Why is normal leakage of fluid vital in the stroma of the cornea?

A

because this fluid is the source of nutrients (glucose and amino acids) for the cornea (avascular)

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18
Q

Early studies showed that maintainence of corneal thickness/water content is ________dependent(a metabolic energy-dependent process)

A

temperature (corneal hydration)

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19
Q

if the cornea is cooled the cornea ____

A

swells

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20
Q

if the conrea has a normal temperature the cornea has __normal/abnormal__thickness

A

normal thickness

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21
Q

what happens in the cornea if there is a continual movement of water, if there is nota a mechanisms present to remove fluid from the stroma ?

A

leads to stromal swelling and loss of transparency

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22
Q

T/F temperature reversal is a phenomenon of the cornea swelling when cooled and returns to normal when at a normal tempature?

Temperature reversal clearly shows that the maintenance of corneal hydration is a metabolic ____-_____ process

A

T

energy-dependent

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23
Q

___ to ___ ml/hr of water is moved by the endothelium from stroma to aqueous humor

A.7-8
B. 6-8
C. 7-10
D 6-10

A

6 to 8

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24
Q

Temperature reversal is clearly demonstrated by eye ____ corneas that swell during refrigeration and return to normal thickness and transparency after grafting.

A

bank

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25
Q

in which membrane is the NA+K+pase pump located in the cornea,?

A

basolateral membrane

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26
Q

NA+K+pase pump has a _____ pump sites/cell

A.1.510^8
B. 310^6
C. 1.510^6
D 310^8

A

1.5 X10^6

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27
Q

What inhibits the NA+K+pase pump?

A

Ouabain

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28
Q

Explain how Ouabian inhibits the NA+K+pase pump

A

stops sodium transport, causes corneal swelling, prevents temperature reversal, and eliminates the transendothelial potential difference

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29
Q

____ pump disruption represents movement of fluid and solutes from the aqueous humor into the __stroma/epithelium/endothelium_____

A

metabolic; stroma

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30
Q

_______ is a lipophyllic cardiac , glycoside is a structurally related compound to ouabain

A

Digoxin

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31
Q

Why can you do corneal grafting?

A

Due to temperature reversal

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32
Q

T/F the sodium pump respond to increases in the endothelial permeability

A

T

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33
Q

Corneal ______ are droplet like accumulation of non banded collagen on the posterior surface of ______ membrane

A

corneal guttata; Descemet’s

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34
Q

Human corneas with guttata have pump site densities of _______ sites per cell.

A. 610^8
B. 710^5
C. 610^6
D 710^6

A

C. 6*10^6

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35
Q

Inflamed edematous cornea has ______ endothelial pump site despite increase permeability

A. increase
B. decrease

A

B. decrease

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36
Q

Human corneas with guttata has large pump sites densities what does this suggest?

A

A greater capacity for the endothelial pump to counteract the leak across the barrier

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37
Q

T/F Sodium potassium ATPase is located in the plasma membrane of cells

A

T

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38
Q

The Sodium potassium ATPase has two ocular functions it controls what and produces what?

A

control of corneal hydration and production of aqueous humor

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39
Q

Corneal stroma readily takes up ______ and excess of it need to be pumped out the maintain corneal _______>

A

water; deturgescence (decrease in swelling)

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40
Q

Sodium ions is transported by Sodium Potassium ATPase is pumped ____ channels between endothelial cells

A

into

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41
Q

Na ions being pushed generates ______ pressure

to which water follows

A

osmotic

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42
Q

The directionality is helped by density of sodium ions in ______ membrane

A

Descemets

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43
Q

Energy source-glucose, Adequate buffer- bicarbonate, and Substrate- calcium, glutathione etc., are ideal for what

A

intraocular irrigating solution

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44
Q

Cornea __pH/bloodpressure__ extremes causes corneal edema

A

pH

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45
Q

T/F Normal saline lacks components of the aqueous humor

A

T

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46
Q

T/F Glutathione bicarbonate ringers solution GBR has the least affect on the corneal thickness compared to NaCl and Lactated ringers solutions

A

T

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47
Q

Which type of intraocular irrigation solution has the most affect on corneal thickness? and has a percentage of ___?

A) 0.8%
B)0.7%
c)0.5%
D) 0.9%

A

0.9 % , NaCl

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48
Q

T/F Lacted Ringer’s and saline solutions of 0.9% overcome the buffering capacity of the vitreous humor

A

F. Aqueous humor

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49
Q

What does it mean if the intraocular irrigating solutions in the cornea are overcoming the buffering capacity?

A

means cornea is unable to resist the pH change

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50
Q

T/F endothelial cells always regenerate

A

F. NEVER regenerate

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51
Q

When endothelial cells are lost (due to trauma , aging, disease) endotheiall wounds are covered by the spreading of cells from ____ areas

A

adjacent

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52
Q

T/F In larger defects of the corneal endothelium (like keratoconus problems) a very small amount of cell migration occurs in order to heal the wound

A

F. In larger defects of the corneal endothelium (like keratoconus problems) a MORE EXTENSIVE cell migration occurs in order to heal the wound

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53
Q

T/F Keratoplasty is surgery on the cornea , refers to a corneal graft procedure

A

T

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54
Q 
After Keratoplasty(corneal graft) , migration of endothelial cells over the wound edge go to the \_\_center/periphery\_\_ and establish \_\_gap/tight\_\_ junctions to establish \_\_epithelial/endothelial
\_\_ barrier
A

periphery, tight, endothelial

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55
Q

For proper corneal function there must be adequate endothelial cell __volume/density___ and __large/small/uniform___ size and shape

A

density, uniform

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56
Q

polymegathism is a change in cell __shape/size__

A

size

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57
Q

Pleomorphism is a change in cell __size/shape__

A

shape

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58
Q

T/F polymeagthism and pleomorphism stay the same throughout your life

A

F. change with age

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59
Q

The degree of uniformity of cell size is deteremined by measuring the areas of the ____apical/base__ membranes of a populations of cells and calculting the coefficitne of variation of cell size

A

apical

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60
Q

The Coefficient of Variation (CV) is the standard deviation of __median/mean__ of cell area over the __median/mean__ of cell area

A

mean , mean

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61
Q 
the normal CV(coefficinet of variation) of the endothelium in the cornea is ?
A) 0.35
B)0.40
C)0.25
D)0.30
A

0.25

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62
Q

What does it mean if the CV(coefficinet of variation)> 0.25 , is it polymegathism or pleomorphism ?

A

the cell size is variable = polymegathism

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63
Q

T/F As polymegathism increases with an increased CV cells start to look more uniform.

A

F. look more variable

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64
Q

Healthy cornea has ____to___% ___hexaganoal/octogonal__ cells

A) 80-90
B)70-100
C)70-80
D)80-100

A

70-80, hexagonal

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65
Q

A increase/decrease in hexagonal shape with an increase/decrease in cells with <6 sides shows endothelial stress (cornea) which means it is pleomorphism

A

decrease, increase

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66
Q

Lasik has no significant effect on endothelial cells _____shape/density__ or __percent/shape__ of hexagonal cells with myopia of ___ to ___ diopters

A) 2.25-14.5
B)2.25-10.45
C)3.25 -14.5
D)3.25-15.5

A

density , percent

A)2.25-14.5

67
Q

Why must there be a residual 200 microns of stroma above the corneal endothelium after LASIK?

A

to adequately maintain and protect the corneal endothelial structure and barrier function

68
Q

T/F Laser in situ keratomileusis is a current technology in which corneal stroma is ablated by an excimer laser underneath a lamellar flap

A

T known as LASIK

69
Q 
CV (coefficinet of variation) of cell \_\_\_size/shape\_\_ imporves \_\_\_years after lasik
A)1
B)5
C)4
D)3
A

size

D)3years

70
Q

If there is a change in CV after lasik what was the likely affect? and in what percentage of patients had a history of it?

A)30%
B)50%
C)91%
D)81%

A

the likely effect in change of CV is from contact lens removal , because they had a histroy of contact lens wear

91%

71
Q

T/F penetration keratoplasty is the removal of full-thickness “button” of cornea and replacement with donor corneal tissue–also known as PK

A

T

72
Q

In recent studies of corneal grafts(PK) a long term follow-up of clear graft 15-33 years after the procedure was done. The endothelial cell count range was from ___ to ___ cells/mm^2

A)600-1243
B)675-1200
C)575-1200
D)575-1243

A

D)575-1243

73
Q

In recent studies of corneal grafts(PK) a long term follow-up of clear graft 15-33 years after the procedure was done.
It was found that an endothelial cell loss rate of ___% from 3-5 years after PK, 13x rate decrease in normal corneas which is ___%

A)7.8% , 0.6%
B)8.7%. 0.6%
C)8.7%, 0.5%
D)7.8%, 0.5%

A

A)7.8% , 0.6%

74
Q

Intraocular lens implantation can lead to __epithelial/endothelial__ cell loss

A

endothelial

75
Q 
The mean overal endothelial cell loss in IOL (intraoclular ens implantation) surgery is \_\_\_\_ after \_\_\_ months after 
A)8.5%  ,12
B)9.0%. 10
C)10%, 10
D)11%, 12
A

8.5% , 12 months

76
Q

what type of anesthesia was used in the study of endothelial cells after phacomulsification with IOL implantatoin? retrobulbar/introbulbar

A

retrobulbar anesthesia

77
Q

T/F phacomulsification is use of ultrasonic vibration to break up a cataract into small fragments and emulsify them , making them easier to suction out of the eye

A

T

78
Q

With KCN (keratoconus) and Type 2 Diabetes:

Endothelial morphology 
 (stays the same/changes)

(Does/Doesn’t) have decrease in cell density

(increase/decrease) CV of cell size and (increase/decrease)% of hexagonal cells

A

changes

doesn’t

increase, decrease

79
Q

With KCN (keratoconus) and Type 2 Diabetes, how much decrease is there in hexagonal cells?

A)30%
B)50%
C)40%
D)80%

A

50%

80
Q

T/F In Keratoconus (KCN) stress on cornea causes epithelial remodeling

A

F. endothelial

81
Q

What other type of disease after a long duration, was found to also decrease cell density besides type 2 diabetes?
(edema/type 1 diabetes/high cholesterol)

A

type 1 diabetes

82
Q

T/F Patients with diseases of long duration also demonstrate a decrease in cell density

A

T

83
Q

Type 1 diabetes (increases/decreases) cell density

A

decreases

84
Q

After ____ years of age there is a (increase/Decrease) in endothelial cell density

A)30
B)40
C)50
D)60

A

40 , decrease

85
Q

Why is special care needed when doing cataract surgery on those with glaucoma or diabetes? and which layer of the cornea is of interest (endothelium/epithelium/bowmans layer)

A

to minimize the surgical stress to the endothelium

86
Q

T/F long-term contact lens wearers have no effect on the corneal endothelium morphology

A

F. there are morphologic abnormatilies of the corneal endothelium

87
Q

What specific type of change is there in long term contact wearers corneal endothelium ? polymegathism/phacomulsification/pleomorphism

A

polymegathism

88
Q

T/F ONLY long term use of polymethylmethacrylate lenses and daily wear soft contact lenses have been reported to effect the corneal endothelium

A

F
polymethylmethacrylate lenses
daily wear soft contact lenses
AND –extended-ear soft contact

89
Q

T/F There is an absence of morphological abnormalities of the endothelium in eyes wearing highly (deoxygen/oxygenated) permeable silicone elastomer lenses

A

oxygenated

90
Q

T/f hypoxia (oxygen deficiency) is responsible for the observed effects on the corneal endothelium of long term use CL wears

A

T

91
Q

What does the coined term CLUE stand for when talking about long-term use contact lens wearers and its effects?

A

contact lens-use endotheliopathy syndrome

92
Q

Cornea is richly supplied with (motor/sensory) nerves

A

sensory

93
Q

T/F the iris is one of the most sensitive tissues in the body

A

F. cornea

94
Q

Cornea is innervated by the (abducens nerve/trigeminal nerve/cranial nerve) via (anterior/posterior) ciliary nerves

A

trigeminal , anterior

95
Q

Which two are not innervated in humans?

bowman’s layer/epithelium/endothelium/ descemt’s membrane/stroma

A

endothelium, descemet’s membrane

96
Q

Most of the receptors in the cornea are what type of receptor?

A

nociceptors (pain)

97
Q

T/F nociceptors when stimulated give perception of pain

A

T

98
Q

Nociceptors usually have the (highest/lowest) threshold for mechanical stimulation

A

lowest

99
Q

T/F because nociceptors have a low threshold abrasion, ulcers , bullous keratophathy have low pain conditions

A

F. extremely painful conditions

100
Q

Stroke, diabetic neuropathy, and herpes simpelx lead to (motor/sensory) denervation

A

sensory

101
Q

What type of denervations causes these two sypmtoms? (sensory/motor) and choose the correct effect.

(Loss/increase) in foreign body sensations cause mechanical cornea damage

(Low/High) incidence of epithelial erosions and neurotrohic ulcers

A

Sensory
loss
high

102
Q

Lasik cause (increase/decrease) corneal and conjunctival sensitiviey up to ____ months of follow up

A)12
B)16
C)20
D)10

A

decrease

B)16

103
Q

Cl wear causes (increase/decrease ) corneal sensitivity

A

decrease

104
Q

T/F Both soft and rigid gaspermeable lens wearers produce a increase in corneal sensitivitly

A

F. DECREASE

105
Q

Atmosphere , aqueous humor, and limbal vasculature is where (oxygen/sodium/water) comes from for corneal metabolism

A

oxygen

106
Q

What three places does oxygen come from for corneal metabolism?

A

atmosphere, aqueous humor, limbal vasculature

107
Q

Compared to tears which one of the three has a low amount of oxygen?
Atmosphere/aqueous humor/ limbal vasculature

the one with the low amount of oxygen is ____mm Hg
the oxygen amount in tears is ___mm Hg

A)40 , 100
B)50, 100
C)40, 155
D) 50, 155

A

aqueous humor

C)40 mmHg 155mm Hg

108
Q

]which one of the three has a high amount of oxygen for corneal metabolism?
Atmosphere/aqueous humor/ limbal vasculature

A

atmosphere

109
Q

Corneal (endothelium/epithelium) consumes 10times more oxygen compared to the (descements membrane/stroma)

A

epithelium, stroma

110
Q

How is oxygen delivered to the cornea when you are asleep or closed-eyed?
(bulbar/superior palpebral/ inferior palpebral conjunctiva)

A

by the vascularized superior palpebral conjunctiva

111
Q

T/F oxygen is delievered at reduced levels

A

T

112
Q 
\_\_\_% of oxygen is delivered at reduced levels with eyelid open and \_\_% with eyelid closed
A)15, 8  
B)21, 10
C)15, 10  
D)21, 8
A

D)21, 8

113
Q

T/F aphakia is the absence of the eye crystalline lense

A

T

114
Q

Post-cataract surgery(aphakia) oxygen tension may (increase/decrease) in the aqueous humor secondary to (increased/decreased) oxygen metabolism by the crystalline lens

A

increase, decrease

115
Q

In aphakia , the oxygen in (atmosphere/aqueous humor/limbal vasculature) supplements that in the tears helping to meet oxygen demands and providing (lower/greater) tolerance to hypoxix stress ( oxygen deficiency)
what is a example of this? (using glasses or CL)

A

aqueous humor
greater
CL

116
Q

Metabolic requirements for nutrients are supplied to the cornea by the (vitreous humor/aqueous humor/limbal vasculature)

A

aqueous humor

117
Q

compared to the aqueous humor (Greater/lesser) amounts of nutrients for the cornea are available in the tears and limbal vessels

A

lesser

118
Q

Glucose can be derived from the glycogen stores in the corneal (endothelium/epithelium)

A

epithelium

119
Q

Hard contact lens wearers (increase/decrease) available oxygen to corneal epithelium with nearly ___% of reserved used up in __ hours of wear

a) 80% 8 hours
b) 80% 12hours
c) 60% 8 hours
d) 60% 12 hours

This results in conreal _____, in that there is a 20% (increase/decrease) in corneal thickness

A

decrease

A) 80% 8 hours

edema

increase

120
Q

With an increase in time, glycogen content in the cornea (decreases/increases) in hard lens wearers compared to soft lens wearers

A

decreases

121
Q

Glucose derived from the (aqueous humor/vitreous humor) or glycogen stores is converted to pyruvate by _____-____ pathway and yields
___ number of ATP per glucose molecules

A)3
B)2
C)4
D)8

A

aqueous humor

embden-meyerhof

2

122
Q

Under hypoxic (oxygen deficent) conditions , increase in (glucose/lactate) producution which causes cornea ____

A

lactate, edema

123
Q

Halo and rainbow formation
increased glare sensitivity
decreases contrast sensitivity
are all symptoms of what?

A

epithelial edema

124
Q

Stromal edema manifests in the (anterior/posterior) direciton because the (anterior/posterior) surface is fixed by which two?

descemets memrane/posterior stroma/ bowman’s membrane/anterior stroma

A

posterior
anterior

bowman’s membrane, anterior stroma

125
Q

Buckling of which two corneal layers gives rise to vertical striae(wrinkles or folds cause by abnormal pressure)?
endothelial/epithelial/stroma/bowman’s layers/ decement’s membrane

A

stroma/descemets membrane

126
Q

Deturgescent (decrease in swelling) can be maintained with a sustaine oxygen level as low as
___mmHg

A)35
B)25
C)20
D)30

A

25

127
Q

T/F Small diameter lenses are permeable to oxygen and have no movement needed for tear exchange

A

F. Small diameter lenses are IMPERMEABLE to oxygen and have GOOD movement needed for tear exchange

128
Q

T/F Large diameter soft lenses are oxygen impermeable for diffusion through the lens itself

A

F. large diameter soft lenses oxygen permeability needed for diffusion though the lens itself, tear pump exchange helps to a lesser extent.

129
Q

Certain byproducts of long term hypoxia and stress that is 12 HETE(12-Hydroxyeicosatetrainoic acid) have the abiity to inhibit what part of the corneal endothelia ?

This occurs in (short/long) term , volume regulation stress (like Cl wearers, and corneas of diabetic patients)

A

Na+K+ATPase metabolic pump

long

130
Q

Contact lens wearers stimulate –> _____ acid this produces–> _____ –>which produces two eicosianoids (12HETE and 8RHDDTrE) —->which diffuses into stroma and inhibits corneal endothelial ____________

A

arachnoid,
P450
Na+K+ATPase metabolic pump

131
Q

Decreased rate of mitosis
Reduced oxygen uptake and glucose utilization
smaller numbers of intercellular desmosomes are all associated with what?

A

Extended wear contact lenses which alter metabolism

132
Q

Because extended wear lenses alters metabolism it (increases/reduces) metabolic activity and compromises the (endothelial/epithelial) barrier function

A

decreases

epithelial

133
Q

Under hypotic conditions there is a increased likelihood of ulcerative microbial keratitis

A

T

Ulcerative microbial keratitis (loss of luster and transparency)

134
Q

Xerophthalmia is caused by lack of vitamin __. This occurs (late/early) in the progression of the vitamin deficiency and found in the corneal (endothelium/epithelium)

A

A
late
epithelium

135
Q

Vitamin A is required for ____ production

A

mucin

136
Q

T/F Xerophthalmia is nonkeratinzaiton of the corneal epithelium

A

F. KERATINIZATION

137
Q

T/F Xerophthalmia is found primarily in children of developing countries

A

T

138
Q

T/F Xerophtalmia is not a disease that shows there is sociaeconomic, cultural , and political conditions that often account for nutritional deficiency

A

F IT IS

139
Q

Volume of adult tear film : __to__microliter

A)8-10
B)8-9
C)7-10
D)7-9

A

7-9

140
Q

what is the max amount of cul-de-dac fluid in microliters?

A10-30
B)20-30
C)40-50
D)10-50

A

20-30 microliter

141
Q

Average drop of topical meds is ____microliters

A)30
B)20
C)40
D)50

A

50 microliters

142
Q

T/F reflex tearing causes slower tear dilution

A

F. FASTER

143
Q

Increased protein in tears of inflamed /infected eyes (increases/decreases) bioavailabitliy of the drug

A

decreases

144
Q

What limits the absorption of hydrophillic , ionized substances and favors penetration of lipid-soluble hydrophobic compounds

A

initial barrier: epithelium (tight junctions)

145
Q

loss of corneal _(endothelium/epithelium)__ greatly enchances penetration of hydrophilic water-soluble pharmacologic agents

A

epithelium

146
Q

_____ is a pharmacologic agent that normally traverse the epithelium via transcellular or paracellular routes

A

gentamicin

147
Q

Stroma of the cornea has a (hydrophilic/hydrophobic) nature which results in a barrier to (aqueous/lipid) based drugs

A

hydrophobic, lipid

148
Q

In the endothelium drug penetration is deteremined mostly by molecular __(shape/size)_

A

size

149
Q

Pressing on lacrimal sac
use viscous drops, suspensions, ointments
slow-release delivery systems
contact lenses
porcine collagen corneal shields
–these are all was to (increase/decrease) what through the cornea ?

A

increase drug penetration

and also increase duratoin of contact of the drug with the ocular surface

150
Q

Drug ___ are used to prolong shelf life of drugs and protect the eye from infection (prevent bacterial growth

A

preservatives

151
Q 
Benzalkonium chloride (BAK) , chlorhexidine digluconate, polyquaternium-1 , and thimerosal
are all what?
A

Drug preservatives

152
Q 
What is the most commonly used drug preservative used :
Benzalkonium chloride (BAK) , chlorhexidine digluconate, polyquaternium-1 , and thimerosal
A

BAK

153
Q 
Which drug preservative has been largely discontinued :
Benzalkonium chloride (BAK) , chlorhexidine digluconate, polyquaternium-1 , and thimerosal
A

due to allergic reaction -thimerosal

154
Q

T/F many topical medication are used to treat ocular disease which include antibiotics , antivirals drugs, antiallergy drugd, and artificial tears for treatment of dry eye

A

T

155
Q

T/F the drug BAK can do damage only do damage to epithelium of the cornea

A

F. Endothelium and epithelium

156
Q

antibacterial action of BAK breaks down bacterial cell _____ and has a _____ property,

A

walls, detergent

157
Q

T/F BAK would not be able to inhibit wound healing

A

F. it does inhibit epithelial wound healing

158
Q

One drop of 0.01% BAK causes (increase/decrease) in permeability of the cornea to flourescein

A

increase

159
Q

T/F pt with severe dry eye have decreased fluorescein permeabilty therefore compromising their corneal epithelial barrier

A

F. INCREASED

160
Q

What drug preservative is used to stabilize BAK ?

A

EDTA (ethulenediaminetetraacetic acid)

161
Q

EDTA chelates __(chloride/postassium/calclium) __which is required for maintenance of tight junctions

A

calcium

162
Q

T/F when possible ophthalmic products should contain EDTA , especially those for dry eye patients

A

F. Should NOT

163
Q

Benzalkonium chloride (BAK) , chlorhexidine digluconate, polyquaternium-1 , and thimerosal

Which two drugs cause endothelial cell degeneration and corneal edema in vitro

A

BAK, chlorhexidine

OCULAR PHYSIOLOGY (13 decks)

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