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6 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Presbyopia |
Lose ability to focus on near objects |
Ciliary body muscle and lens lose elasticity and cause difficulty in reading. Wear bifocal lens to correct |
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Near response |
Accommodation Convergence of visual axes Constriction of pupil |
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Myopia |
Near sightedness- near objects seen clearly but not distant - long eyeball, cornea too curved and lens has too much refractive power |
Corrected by biconcave lens |
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Hyperopia |
Farsightedness- inability to distinguish distant objects- short eyeball, cornea not curved enough and lens has limited refractive power. |
Corrected by convex lens |
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Astigmatism |
Curvature of cornea is uneven. Can occur in near or farsightedness. Image is in front and behind retina. |
Corrected with spherocylindrical lenses |
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Cataract |
Opacity or clouding of lens due to proteins in the lens. Due to ageing, long term exposure to uv light, trauma, diabetes, smoking etc |
Corrected by removing entire lens and fitting with artificial lens |
