What is Farsightedness?

health wellness

Farsightedness is a common eye problem. Typically, it is caused by the ball of the eye being too short, so that the lens focuses an image behind the retina, rather than at the retina. Often, children who suffer from farsightedness outgrow it as they grow and their eyes expand in size. The official medical term is hyperopia.

People with farsightedness can focus on objects that are far away, but can't bring objects closer to them into focus. Its opposite is nearsightedness, or myopia. If you suffer from farsightedness, you will probably wear contacts or glasses to correct your vision. Reading, watching television, and working on a computer are all difficult, uncomfortable, or impossible with farsightedness without corrective lenses.

The eye has to react to the input it takes in, so the muscles controlling the eye squeeze or relax the lens, which changes its shape to focus the light rays. Over time, the lens may become less flexible, or the muscles less effective. As a result, some people develop farsightedness in later life.

Correcting farsightedness is simply a matter of adding a lens in front of the eye's lens that adds convergence to the light rays, so that when they reach the retina, they form an image. The curvature of the corrective lens is dependent on the extent of the farsightedness. This exact curvature is specific to each individual, and may be different for each eye. These figures, the parameters of each lens, are your prescription for glasses or contacts.

Farsightedness can now be corrected with a laser surgery process called Lasik, or laser in-situ keratomileusis. In this procedure, a small piece of the lens is peeled back, then the lens is reshaped with a laser beam and the peeled-back piece is replaced to cover the lens. For farsightedness, the lens is reshaped to be more rounded or convex. For nearsightedness, the lens is flattened. Farsightedness occurs in about twenty-five percent of the population.

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Written by Jane Harmon

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