Hyperopia, or farsightedness, is a disorder where distant objects are usually seen clearly, but close ones do not come into proper focus and are blurred. This occurs when the eyeball is too short or the cornea is too flat, and light rays entering the eye focus behind the retina rather than directly on it.
Hyperopia is often present at birth, but sometimes, vision normalizes as the eyeball lengthens during the growth process. Young adults and children with mild to moderate cases of farsightedness often see close objects clearly because the lens is able to adjust or change its shape. This process is called accommodation. As a person ages, the ability to accommodate often lessens and eyeglasses or contact lenses may be needed.
Farsightedness is a risk factor for closed-angle glaucoma. Therefore, patients with hyperopia should discuss glaucoma testing with their eye care practitioner.
Incidence and Prevalence of Hyperopia
Approximately one-quarter of the U.S. population is hyperopic, and incidence increases with age. At least half of all persons over the age of 65 have some degree of hyperopia. Men and women appear to be affected equally.
Risk Factors for Hyperopia
Because it is often present at birth, there may be a hereditary risk factor. Age is also a risk factor for hyperopia.
Causes for Hyperopia
Hyperopia results when the eyeball is too short or the cornea is too flat and the lens is unable to adjust its shape to see close objects clearly (the process called accommodation).
Signs and Symptoms of Hyperopia
Most children and young adults with mild to moderate hyperopia do not experience symptoms because of the lens's ability to accommodate. Older persons and those with more severe hyperopia may experience these symptoms:
- Achy feeling in eyes
- Blurred vision of close objects
- Eye strain
A diagnosis of hyperopia can be made only after a basic eye examination performed by an ophthalmologist or an optometrist.
Treatment for Hyperopia
Treatment for farsightedness is prescription eyeglasses or contact lenses. Wearing the glasses or contact lenses allows the patient to experience normal, or dramatically improved, vision. Many farsighted people wear their glasses only when doing close work, such as reading or sewing.
A number of surgical procedures are used to correct refractive errors, including photorefractive keratotomy, LASIK, and clear lens replacement therapy. Some of these procedures are appropriate for hyperopia, and in many cases, surgical correction can make eyeglasses unnecessary. Not every patient is a good candidate for surgical correction. Surgery is not recommended for people under the age of 18 because their eyes are still growing.
There is no way to prevent hyperopia. Eye health can be supported by the following:
- Eating a healthy diet that is rich in vitamins A and C
- Protecting the eyes from excessive amounts of ultraviolet light by wearing sunglasses when outside
- Drinking adequate fluids to prevent eye dryness
- Protecting the eyes when working with hazardous or caustic substances
- Having regular eye exams