Vision Eye Conditions





Causes: Astigmatism occurs when the cornea is misshapen to some degree, causing light to focus improperly on the retina.

Symptoms: Astigmatism is a common condition and may affect many people to some degree or another. Symptoms may include:

   : Blurred or distorted vision

   : Headaches

   : Eye strain

   : Fatigue

Diagnosis and Treatment: Most astigmatism is treatable by eyeglasses, contact lenses, or refractive surgery.  

 Photo: National Institutes of Health



Amblyopia (Lazy Eye)

Causes: Amblyopia, or lazy eye, is a loss of vision or lack of development of central vision in one eye caused by inadequate use during early childhood. Amblyopia may develop from conditions such as a squint or strabismus (eyes not positioned straight), congenital cataract, uncorrected high near-sightedness (myopia) or far-sightedness (hyperopia) in one eye or both eyes and severe ptosis (droopy eyelids).

Symptoms: While symptoms are not always obvious, they typically appear during early childhood and may include:

   : Noticeably favoring one eye

   : Eye turning in, out or up

   : Closing of one eye

   : Squint

   : Headaches or eyestrain

Diagnosis and Treatment: Comprehensive eye exams during childhood are highly recommended and can lead to the diagnosis of amblyopia at an early age, increasing the chance for a complete recovery. The most effective treatment is to encourage the use of the amblyopia eye, which may include prescription lenses, prisms, vision therapy and eye patching.



Color Vision Deficiency

The term “color blindness” is not entirely accurate. A more accurate statement may indicate that a person is “color deficient.” Color deficiency is an inherited genetic trait that affects one in 12 males and one in 100 females.

Symptoms: Only in very rare cases is color vision deficiency so severe that the individual can detect no color at all. In most cases, the ability to distinguish certain colors is simply less than normal. Red-green color deficiency is the most common form of this condition, but some people may also have difficulty distinguishing blue and gray.

Diagnosis and Treatment: Color vision deficiency is not typically indicative of disease, and is not typically correctable in most cases, although special tinted lenses may help. Occupational counseling may be helpful for those individuals who are color deficient.  




Myopia (Nearsightedness)

Causes: Myopia is the medical term for nearsightedness. It is a condition in which 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 is such that light entering the eye cannot be properly focused on the retina.


   : Difficulty seeing distant objects

   : Lack of classroom participation due to difficulty seeing the chalkboard

Diagnosis and Treatment:
Myopia is a very common problem affecting about 30 percent of Americans, and can be detected by a comprehensive eye exam.
It generally develops before the age of twenty. Corrective lenses (glasses or contact lenses) or refractive surgery may be used in the treatment of myopia, depending on the severity of the condition and the preference of the patient.


Presbyopia (Farsightedness)

Causes: Presbyopia usually occurs at or around age 40, when the natural lens inside the eye loses flexibility,
making it difficult to focus on objects or print at close range. It is a natural process of aging, not a disease,
and cannot be prevented. 


: The need to hold reading materials at a distance  

: Blurred vision and eye fatigue, including headaches when doing close work ("arms are too short")  

Diagnosis and Treatment: A comprehensive eye exam can detect presbyopia. Your eye care specialist may prescribe single vision reading lenses or multifocal lenses, such as bifocals, trifocals, or progressive ("no line")
lenses. Contact lenses are also available to correct presbyopia. Since the eye continues to change in the aging process, changes in your prescription may be required periodically.





Spots and Floaters

Causes: Small cloudy specks of various sizes may form within the eye. These spots are usually encapsulated 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 and are usually considered harmless. They may also occur later in life due to aging or certain eye diseases.

Symptoms: Spots or floaters move as your eyes move. They rarely limit vision, but may be bothersome and are noticed when looking into space or at a blank wall when sufficient light is present.

Diagnosis and Treatment: Although floaters are generally considered harmless, they may be indicative of more serious problems that can be detected only 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. 




Causes: 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 prior to age seven, and may continue undetected or uncorrected into later life.

Symptoms may 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

Diagnosis and Treatment:
One common misconception of strabismus is that a child will outgrow the condition. This is not true. In fact, without treatment, the condition may worsen and cause other eye conditions, including amblyopia (lazy eye).

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 may include:

   : Eyeglasses

   : Prisms (a lens application that helps focus the light entering the eye on the retina)

   : Vision therapy

   : Surgery