When you're farsighted a condition called hyperopia (hi-pur-O-pe-uh) - you may see objects that are far away clearly but have difficulty focusing on objects close to you.
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| Eye Exercises For Farsightedness |
In most cases people are farsighted because their eyeball is shorter than normal from front to back. The rays of light coming into the eye aren't sharply focused at the time they reach the retina. Instead the point of focus fails behind the retina. This problem can also be caused by either a cornea or a lens that doesn't have a steep enough curvature.
Farsightedness runs in families and is usually present at birth. Most young people don't know they have the condition because their lens is flexible and able to accomodate enough to focus the light sharply on the retina. But constant overworking of the muscles that make your lens assume a more tightly curved shape can leave you with aching or burning eyes, headaches, fatigue or blurred vision after you've done a lot of reading or close-up work.
As you grow older your lens becomes less elastic and unable to make the necessary shape adjustment. Most farsighted people need corrective lenses by middle age.
The correction of farsightedness is accomplished with a convex lens, which is thicker in the center than at the edges. This moves the point of focus forward, onto the surface of your retina. Surgery also is an option that's becoming more popular, but the procedure is complicated and therefore is not performed as commonly as the surgery to correct nearsightedness.
Astigmatism
In a normal eye the dome of your cornea is curved evenly and smoothly in all directions. This allows for the round ball that you are looking at, for example, to be focused perfectly on your retina and thus be perceived as a round ball. Some corneas, however, aren't evenly and smoothly curved. Instead they are curved more steeply in one direction than in another. A round ball viewed through such a cornea will be seen as oblong. Typically you'll see the distortion in one direction more than in others, either horizontally, vertically or diagonally. This distortion of the image is called astigmatism (uh-STIG-muh-tiz-um).
Astigmatism is in most instances inherited, but sometimes it may develop following an injury or a disease. About half the people who are nearsighted also have some astigmatism. The condition generally doesn't change throughout your life.
You may not notice the distortion caused by minor degrees of astigmatism. More serious astigmatism can be corrected with a cylindrical lens that counteracts the uneven curvature of your cornea. The same lens you use to correct nearsightedness or farsightedness can be made to neutralize your astigmatism as well. Another option is surgery to reshape the curvature of your cornea - it is similar to the surgery used to correct nearsightedness and farsightedness.
Second sight
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| Eye Exercises For Farsightedness |
Some older adults are surprised - and delighted - by what is called second sight. After using reading glasses or bifocals for many years, you suddenly discover that your vision has improved. You no longer need the reading correction.
This happens when the lens of your eye becomes thicker as you age. It produces some nearsightedness, which can correct your presbyopia at the same time. However, not all of the news is good. The vision change is usually a sign that a cataract is forming, which ultimately clouds your vision. So it's a good idea to inform your eye doctor if you notice the development of second sight. To find out more, you can check out Eye Exercises For Farsightedness.