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19 Cards in this Set
- Front
- Back
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Normal intraocular pressure
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10 - 21 mm Hg
over 21 = Glaucoma |
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Aqueous Humor vs. Viteous Humor
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aqueous humor - clear watery fluid (bathes & nourishes lens & cornea)
vitreous humor - gel substance inside eye in front of retina. Become more liquid with aging |
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refraction
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ability of eye to bend light rays so that they fall on retina.
when light doesn't focus properly it is called a refractive error |
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myopia
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can see near objects clearly but far objects are blurry. (near-sightedness)
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hyperopia
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can see distant objects clearly but close up objects are blurred. (far-sightedness)
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Astigmatism
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unevenness of the cornea. results in visual distortion
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Presbyopia
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form of hyperopia (far-sightedness) that occurs as a normal sign of aging, usually around 40
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Conjunctiva
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a transparent mucous membrane that cover inner surface of the eyelids.
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sclera
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white of your eye (collagen fibers meshed together)
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cones vs. rods
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Cones- receptive to colors in bright enviroments
Rods- stimulated in dark enviroments |
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Gerontologic Changes-Visual
Eyebrows & Eyelashes |
Loss of pigment in hair
(graying eyebrows and eyelashes) |
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Gerontologic Changes-Visual
Eyelids |
loss of orbital fat, decrease muscle tone, tissue atropy, prolapse of fat into eyelid tissue (ptosis)
drooping of eyelid |
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Gerontologic Changes-Visual
Conjunctive |
Tissue damage related to chronic exposure to UV light or to other chronis enviromental exposure. (Small yellowish spot usually on the middle of the conjunctiva)
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Gerontologic Changes-Visual
Sclera |
Lipid deposition (scleral color yellowish as opposed to blueish)
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Gerontologic Changes-Visual
Cornea |
-Cholesterol Deposits = milky or yellow ring encircling cornea
-Decrease in water content, atrophy of nerve fibers = decrease in corneal sensitivity & reflex Lipid deposition - blurring of vision |
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Gerontologic Changes-Visual
Lacrimal Apparatus |
decreased tear secretion = dryness
Malpositioning of eyelids = tears overflowin lid margins and not draining thru puncta = tearing, irritated eyes |
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Gerontologic Changes-Visual
Iris |
increased rigidity = decrease pupil size
dilator muscle atrophy or weakness = slower recovery time of pupil size after light stimulation loss of pigment = change of iris color ciliary body becomes smaller, stiffer - decrease in near vision and accomodation |
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Gerontologic Changes-Visual
Lens |
biochemical changes in lens proteins, oxidative damage, chronic exposure of UV light = CATARACTS
rigidity of lens= presbyopia opacities in the lens = complaints of glare, night vision impaired Accumulation of yellow substances - yellow color of lens |
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Gerontologic Changes-Visual
Retina |
decrease in cones - changes in color perception (especially blue and violet)
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