Warning Signs of Eye Trouble
Blurry vision, spots, glare at night -- these are common eye complaints that can be harmless annoyances or an early sign of disease. In the slides ahead, we explore several eye problems and offer two quick eye tests. You'll see the world through eyes that have floaters, cataracts, myopia, and glaucoma. Be sure to see an eye doctor promptly for any concerns.Color Blindness Test
Which number do you see in the far left? If it's "3," you probably have normal color vision. If it's a "5," you may be colorblind. This view is simulated in the center panel and represents a mild color vision deficiency. About 10% of men are born colorblind, but few women. Complete color blindness (very rare) is simulated at right. No number is visible. Tinted glasses may help the colorblind see better
Farsightedness (Hyperopia)
Most of us are born with mild farsightedness, but normal growth in childhood often corrects the problem. When it persists, you may see distant objects well, but books, knitting, and other close objects are a blur. Hyperopia runs in families. Symptoms include trouble with reading, blurry vision at night, eyestrain, and headaches. It can be treated with glasses, contacts, or surgery in some cases.
Presbyopia
Just like gray hair or wrinkles, trouble reading fine print is a sign of aging. Called presbyopia -- or "old eye" in Greek -- symptoms appear in the 40s. The eyes' lenses become less flexible and can't change shape to focus on objects at reading distance. The solution: Reading glasses or bifocals, which correct both near and distance vision. If you wear contacts, one eye can be corrected for reading and the other for distance.
Nearsightedness: What Happens
Typically, an eyeball that's too long causes myopia. But an abnormally shaped cornea or lens can also be to blame. Light rays focus just in front of the retina, instead of directly on it. This sensitive membrane lines the back of the eye (seen in yellow) and sends signals to the brain through the optic nerve. Nearsightedness often develops in school-age children and teens, who need to change glasses or contacts frequently as they grow. It usually stabilizes by the early 20s.
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