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We are happy to provide you with some basic information on several common vision conditions. Select from the following list or scroll to learn more about the symptoms and treatments for:

Emmetropia (Normal Vision)

When the shape and length of the eye are perfectly matched, the eye is said to be emmetropic. Emmetropia is the medical term for 20/20 vision without the need for corrective lenses, contact lenses, or reading glasses. It occurs when the optical power of the eye perfectly focuses an image on the retina, giving a person “perfect” vision.

Hyperopia (Farsightedness)

Think of a hyperopic eye as being UNDERPOWERED or UNDERMAGNIFIED.  Since the human eye focuses more on near objects, hyperopic individuals often see better in the distance than up close.

Causes: Hyperopia is usually caused by a flat cornea (window), a short eyeball, or both.  This leaves the eye underpowered where light tries to focus behind the retina (film).

Symptoms: tired eyes, fluctuating vision, possible double vision, frequent frontal headaches that may worsen late in the day or after extended near work (computer, sewing, reading).  Symptoms can vary widely and tend to increase with age.  Some individuals may not have any symptoms at all.

Hyperopia commonly runs in families. Babies are often born with hyperopia but usually outgrow the condition as the eye develops. About 1/4 of the population is afflicted with hyperopia and it can be a risk factor for glaucoma, a more serious condition. Fortunately, hyperopia is correctable with eyeglasses or contact lenses. There are also new surgical procedures that can correct hyperopia.

Recommended Link
American Optometric Association — Hyperopia

Myopia (Nearsightedness)

Think of a myopic or nearsighted eye as being OVERPOWERED or OVERMAGNIFIED. This results in near objects being seen clearly while distant objects are blurred. Myopia usually develops in early childhood, though it sometimes develops in early adulthood. In rare cases, myopia can lead to more serious conditions such as retinal detachment.

Causes: Myopia is considered a genetic disorder. If your parents are nearsighted, you will have a greater chance of developing the condition. Myopia is usually caused by a steep cornea (window), a long eyeball, or both.  This leaves the eye overpowered where light tries to focus in front of the retina (film). Another risk factor is excessive “near work” – work involving fine detail or focusing on close objects.

Symptoms: trouble seeing distance objects (TV, blackboard, road signs), squinting, holding books excessively close or getting frequent headaches.

Myopia can usually be corrected with eyeglasses or contact lenses. Although rare, myopia can gradually worsen throughout life, a condition known as myopic creep. Myopia can also be corrected by LASIK surgery.

Recommended Link                                                                       
American Optometric Association — Myopia

Astigmatism

For the eye to bend light correctly, the cornea (window) should be dome-shaped, like a basketball. People with astigmatism tend to have an irregular or football shaped cornea. This causes entering light rays to focus on two different points inside the eye, resulting in a distorted view when looking at objects near and far. Although the cause of astigmatism is unknown, it tends to run in families and usually becomes stable by adulthood.

Even small amounts of astigmatism can distort the details of vision. Fortunately, it can be corrected successfully with eyeglasses, contact lenses and refractive surgery.

Recommended Link
American Optometric Association — Astigmatism

Presbyopia

As people get older, usually when they hit their mid to late 40s, a condition called presbyopia can set in. Presbyopia is the inability to focus on objects brought near to the eye. One usually notices that it’s harder to read or use the computer. Reading glasses and contact lenses are a way to improve near vision.

Presbyopia is a natural consequence of the aging process. There is no cure, though researchers are constantly looking for one. Even if someone has never had vision problems before, they can still develop presbyopia. It may seem to occur suddenly, but actually occurs over a long period of time. Symptoms include having to hold things at arm’s length to see them clearly, eye strain, fatigue, and headaches from near work.

Recommended Link
American Optometric Association — Presbyopia

Computer Vision Syndrome

Computer vision syndrome (CVS) affects three out of four computer users. It is a series of symptoms related to extended periods of computer usage. Though it is no cause for panic, measures can be taken to relieve symptoms of CVS.

Symptoms: CVS can appear as a variety of symptoms. Headaches, eye strain, neck and back aches, sensitivity to light, blurred vision, double vision, and dry or irritated eyes are all possible problems related to CVS.

Risk Factors: Any computer user can develop CVS. Your vision, your computer, and the environment where you use your computer are all factors which can lead to CVS.

Recommended Link
Healthy Computing Articles — Computer Vision Syndrome

Amblyopia

Amblyopia, commonly called lazy eye, occurs when one eye develops differently than the other. There are several reasons this can occur (1) A difference in focusing ability between the two eyes causes one eye to be ignored. (2) The eyes may be misaligned causing the brain to ignore one eye in order to avoid double vision. (3) A child may be born with a clouded lens or cornea preventing a clear picture from focusing on the retina. Essentially, any time one eye is used less than the other, it has the potential to become weaker, more blurred and thus “lazy.”

Symptons: It’s not always easy to detect amblyopia. Sometimes a child will noticeably favor one eye over the other. The child may also frequently bump into things on one side. If the child’s good eye sees well and the eyes appear aligned, there may be no symptoms. The best way to tell if your child has lazy eye is through a complete exam around six months and three years. Early diagnosis can prevent amblyopia from leading to more serious problems such as loss of the ability to see three dimensions or functional blindness in the amblyopic eye.

Treatment: Most of the time amblyopia cannot be entirely corrected. The amblyopic eye will almost always be a bit weaker than the other. However, with treatment, vision in the amblyopic eye can be improved to some extent. Treatment involves encouraging the weak eye to develop. This is done using eye patches, vision therapy, glasses, or a combination of the three. The strong eye may be patched to encourage the weak eye to develop. Vision therapy can help to correct improper use of the eyes. If a focusing error is at the root of the problem, then glasses may reduce the error. Most of the time the, amblyopic eye will always require glasses or a contact lens.

Recommended Link
National Eye Institute Amblyopia Resource Guide