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Light that enters your eyes is focused to form an image on your retina. The optics of your visual system have a total refractive power of about +60 D - about +20 D from the lens in your eye and + 40 D from the curved shape of your cornea. Surgical procedures to correct vision generally do not work on the lens; they work to reshape the cornea. In the most common procedure, a laser is used to remove tissue from the center of the cornea, reducing its curvature. This change in shape can correct certain kinds of vision problems.
60. A cataract is a clouding or opacity that develops in the eye’s lens, often in older people. In extreme cases, the lens of the eye may need to be removed. This would have the effect of leaving a person
A. Nearsighted.
B. Farsighted.
C. Neither nearsighted nor farsighted.
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