Hyperopia

What Is It?

Farsightedness, also called hyperopia, is a condition in which a person has difficulty seeing objects close to the eye, although vision of distant objects is good.

In most cases, farsightedness is an inherited condition that is caused by an abnormally short eye, as measured from front to back. This reduces the distance between the cornea (the clear film that covers the front of the eye) and the retina (the light-sensitive layer at the back of the eye). As a result, images tend to focus behind the retina, rather than on the retina itself. Sometimes, the eye is able to compensate partially or totally for this focusing problem through a process called accommodation. In accommodation, tiny ciliary muscles within the eye contract, altering the shape of the lens and bringing the viewed object into focus.

Symptoms

Symptoms of a farsightedness can include:

• Difficulty seeing objects that are fairly close to the eye — Specifically, you may notice that your vision blurs when you try to read a book, thread a needle or assemble small pieces of a model.
• Headaches — These may be related to overworked ciliary muscles that are struggling at accommodation.
• Crossed eyes in children — Severely farsighted children can appear cross-eyed (both eyes turn inward toward the nose) because of extreme efforts at accommodation. This condition, called accommodative esotropia, usually develops between the ages of 2 and 3. It can be constant or intermittent.

During childhood and adolescence, many people who have inherited short eyes do not show symptoms of farsightedness because their youthful eyes are so good at accommodation. With time, however, age-related changes in the lens can make accommodation less effective, and symptoms of farsightedness eventually appear.

Diagnosis

After reviewing your symptoms, your doctor will perform a thorough eye examination, including tests of visual acuity (how well you can see).

Expected Duration

Farsightedness is usually a lifelong condition, although symptoms may not be noticeable during childhood.

Prevention

Most farsightedness is inherited and cannot be prevented.

Treatment

If you are farsighted, your doctor probably will prescribe eyeglasses or contact lenses to correct your problem. The lenses used in both of these treatments are thick in the center and thinner around the edges, which brings the viewed image forward into proper focus on the retina.