What Is It?
A person with farsightedness, also called hyperopia, has difficulty seeing objects close to the eye. They can see distant objects well.
In most cases, farsightedness is an inherited condition caused by an eye that is too short 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). Because this distance is shorter, images tend to focus behind the retina, rather than on the retina. Usually, the eye is able to compensate, partially or totally, for this focusing problem through a process called accommodation. This is especially true in younger people. In accommodation, tiny muscles within the eye contract, altering the shape of the lens and bringing the viewed object into focus.
Symptoms of a farsightedness can include:
Difficulty seeing objects fairly close to the eye - 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 eye muscles that are struggling to bring objects into focus.
Crossed eyes in children - Severely farsighted children can appear cross-eyed (both eyes turn inward toward the nose) because of extreme efforts to focus. This condition, called accommodative esotropia, usually develops in early childhood. It can be constant or show up from time to time.
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 accommodating. With time, however, age-related changes in the lens can make the process of accommodation less effective, and symptoms of farsightedness eventually appear.