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Vision Problems

Amblyopia (Lazy Eye)

      Amblyopia is an eye condition that results in the functional non-use of one eye. This is the result of a problem focusing an image on the retina. It is caused by either a refractive error or an ocular muscle imbalance. The symptoms of amblyopia are not always obvious. They can include:

- favoring one eye
- a tendency to bump into objects on the left or right
- the inability to focus both eyes together
- peripheral vision unaffected

If amblyopia is diagnosed early, the odds of recovery improve significantly. Amblyopia usually appears in early childhood and can be treated with vision eyeglasses or vision therapy. This condition is one of the main reasons why eye exams in children should begin around six months of age. When amblyopia is diagnosed later in life, treatment is more difficult and often less effective. The condition can lead to blindness in the affected eye.


Astigmatism occurs when the cornea is misshapen to some extent. This causes light to focus improperly on the retina. Symptoms of astigmatism include:

- distorted or blurry vision
- headaches
- eye strain
- fatigue

Astigmatism is most often treated with eyeglasses, contact lenses or refractive surgery.

Color Vision Deficiency

The term "color blindness" is somewhat misleading. Eye professionals prefer the term "Color deficient". Color deficiency is an inherited genetic trait that affects about 1 out of 12 males and 1 out of 100 females. Only in rare cases is color vision deficiency so severe that the individual has no color vision. In most cases, an individual is less able to distinguish certain colors. Red-green color deficiency is the most common form of this condition, followed by a difficulty distinguishing blue and gray. Color vision deficiency is not typically indicative of disease and is not typically correctable in most cases. Special tinted lenses and occupational counseling can be of help. Hyperopia (Farsightedness)

Hyperopia is a condition where distant objects appear clearly, but those close up may appear blurred or cause eye strain when trying to focus. Like myopia, the condition is caused when the shape of the eyeball or cornea causes the light entering the eye to be improperly focused on the retina. Symptoms of hyperopia may include:

- difficulty focusing on objects close up
- eye strain
- eye aches or burning sensations
- fatigue or headache following work demanding close-up vision
- difficulty reading
eye irritability following periods of sustained concentration at near distances

Normal vision screenings may not be sufficient to diagnose hyperopia. A very comprehensive vision exam will usually detect the condition. Corrective lenses can be prescribed for hyperopic patients.

Myopia (Nearsightedness)

Myopia is a condition where objects that are up close are usually in focus and clear, but those at a distance (outside of arms length) appear blurred. Like hyperopia, the condition is caused when the shape of the eyeball or cornea causes light entering the eye to be improperly focused on the retina. Symptoms of myopia may include:

- difficulty seeing distant objects
- lack of classroom participation due to difficulty seeing the chalkboard
- blurred vision

Myopia is a very common vision problem, affecting about 30 percent of Americans. It can be detected by a comprehensive eye exam. It most often develops before the age of twenty. Corrective lenses (glasses or contact lenses) or refractive surgery can be used to treat myopia, depending on the severity of the condition and the preference of the patient.


Presbyopia usually occurs around age 40, and is the result of the natural lens inside the eye losing flexibility. This causes difficulties in focusing on objects or print close up. It is not a disease, but is a natural process of aging and cannot be prevented. Symptoms of the onset of presbyopia include:

- The need to hold reading materials at a distance
- Blurred vision, eye fatigue and headaches

A comprehensive eye exam can detect presbyopia. Your eye doctor may prescribe single vision reading lenses or multifocal lenses, such as bifocals, trifocals or progressive ("no line") lenses. Contact lenses can also correct presbyopia. Because the eye continues to change as an individual ages, changes in the lens prescription may be periodically required.

Spots and Floaters

Small cloudy specks of various sizes may form within the eye. These spots are usually in the vitreous fluid, a liquid substance that fills the posterior two-thirds inside of the eye. They are caused by protein deposits trapped in the eye before birth. They are usually considered harmless. They may also occur later in life due to aging or certain eye diseases. Spots or floaters move as your eyes move. They rarely limit vision, but may be bothersome and most noticeable when looking into space or at a blank wall under sufficient light.

Although floaters are generally considered harmless, they may be indicative of more serious problems that can be detected by a comprehensive eye exam. Your eye care specialist can examine your eyes and determine if you may be at risk for, or have developed, a more serious problem that requires treatment.

Strabismus (Misalignment of the eyes)

Difficulty with eye muscle balance can cause one or both eyes to turn in, out, up, or down. This condition typically appears in young children before the age of seven, and may continue undetected or uncorrected into adulthood. The symptoms of strabismus can include:

- one or both eyes out of alignment as the person looks at or tries to focus on an object
- double vision
- headaches and nausea when trying to focus

Many people incorrectly believe that strabismus can be outgrown in children. This is incorrect and without treatment, the condition may worsen and cause other eye conditions, including amblyopia.

The American Optometric Association recommends a pediatric eye exam before six months and again at age three. (If there is a family history of strabismus, your eye care professional may recommend a more frequent examination schedule.) If detected early, strabismus can often be corrected. Treatment for misaligned eyes can include:

- eyeglasses
- prisms (a lens application that helps focus the light entering the eye on the retina)
- vision therapy
- vision surgery - LASIK and other surgeries

The National Eye Institute (A Division of the National Institutes of Health) offers excellent resources about vision, eye care and contact lenses. This site is available in both English and Spanish. The Optometrists Network provides detailed information for parents about children and vision care.

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