Amblyopia/Lazy eye

Lazy eye, or amblyopia, is the loss or lack of development of central vision in one eye that is unrelated to any eye health problem and is not correctable with lenses. It can result from a failure to use both eyes together. Lazy eye is often associated with crossed-eyes or a large difference in the degree of nearsightedness or farsightedness between the two eyes. It usually develops before age six and it does not affect side vision.

Symptoms may include noticeably favoring one eye or a tendency to bump into objects on one side. Symptoms are not always obvious.

Treatment for lazy eye may include a combination of prescription lenses, prisms, vision therapy and eye patching. Vision therapy teaches the two eyes how to work together, which helps prevent lazy eye from reccurring.

Early diagnosis increases the chance for a complete recovery. This is one reason why the American Optometric Association recommends that children have a comprehensive optometric examination by the age of six months and again at age three. Lazy eye will not go away on its own. If not diagnosed until the pre-teen, teen or adult years, treatment takes longer and is often less effective.

 

Astigmatism

Astigmatism is a vision condition that occurs when the front surface of your eye, the cornea, is slightly irregular in shape. This irregular shape prevents light from focusing properly on the back of your eye, the retina. As a result, your vision may be blurred at all distances. People with severe astigmatism will usually have blurred or distorted vision, while those with mild astigmatism may experience headaches, eye strain, fatigue or blurred vision at certain distances.

 

Binocularity/Eye coordination

Binocularity is the ability of both eyes to work together as a team. Each of your eyes sees a slightly different image and your brain, by a process called fusion, blends these two images into one three-dimensional picture. Good eye coordination keeps the eyes in proper alignment. Eye coordination is a skill that must be developed. Poor eye coordination results from a lack of adequate vision development or improperly developed eye muscle control. Although rare, an injury or disease can cause poor eye coordination.

Because the images seen by each eye must be virtually the same, a person usually compensates for poor eye muscle control by subconsciously exerting extra effort to maintain proper alignment of the eyes. In more severe cases, the muscles cannot adjust the eyes so that the same image is seen and double vision occurs. Since the brain will try to avoid seeing double, it eventually learns to ignore the image sent by one eye. This can result in amblyopia, a serious vision condition commonly known as lazy eye.

Some signs and symptoms that may indicate poor eye coordination include double vision, headaches, eye and body fatigue, irritability, dizziness and difficulty in reading and concentrating. Children may also display characteristics that may indicate poor eye coordination including covering one eye, skipping lines or losing their place while reading, poor sports performance, avoiding tasks that require close work and tiring easily.
Since poor eye coordination can be difficult to detect, periodic optometric examinations, beginning at age six months and again at age three years are recommended. Poor eye coordination is often successfully treated with eyeglasses and/or vision therapy. The success rate for achieving proper eye coordination is quite high. Sometimes, eye coordination will improve when other vision conditions like nearsightedness or farsightedness are corrected. In some cases, surgery may be necessary.

 

Color Vision Deficiency

Color vision deficiency means that your ability to distinguish some colors and shades is less than normal. It occurs when the color-sensitive cone cells in your eyes do not properly pick up or send the proper color signals to your brain. About eight percent of men and one percent of women are color deficient.

Red-green deficiency is by far the most common form and it results in the inability to distinguish certain shades of red and green. Those with a less common type have difficulty distinguishing blue and yellow. In very rare cases, color deficiency exists to an extent that no colors can be detected, only shades of black, white and grey.

Since many learning materials are color-coded, it is important to diagnose color vision deficiency early in life. This is why the American Optometric Association recommends a comprehensive optometric examination before a child begins school.

Color vision deficiency is usually inherited and cannot be cured, but those affected can often be taught to adapt to the inability to distinguish colors. In some cases, a special red tinted contact lens is used in one eye to aid persons with certain color deficiencies.

 

Hyperopia

Farsightedness, or hyperopia, is a vision condition in which distant objects are usually seen clearly, but close ones do not come into proper focus. Farsightedness occurs if your eyeball is too short or the cornea has too little curvature, so light entering your eye is not focused correctly. Common signs of farsightedness include difficulty in concentrating and maintaining a clear focus on near objects, eye strain, fatigue and/or headaches after close work, aching or burning eyes, irritability or nervousness after sustained concentration.

 

Myopia

Nearsightedness, or myopia, is a vision condition in which near objects are seen clearly, but distant objects do not come into proper focus. Nearsightedness occurs if your eyeball is too long or the cornea has too much curvature, so the light entering your eye is not focused correctly.

 

Presbyopia

Presbyopia is a vision condition in which the crystalline lens of your eye loses its flexibility, which makes it difficult for you to focus on close objects. Presbyopia is a natural part of the aging process of the eye, and it usually becomes noticeable in the early to mid-forties. It is not a disease and it cannot be prevented. To help you compensate for presbyopia, your optometrist can prescribe reading glasses, bifocals, trifocals or contact lenses. You may only need to wear your glasses for close work like reading, but you may find that wearing them all the time is more convenient and beneficial for your vision needs. Since the effects of presbyopia continue to change the ability of the crystalline lens to focus properly, periodic changes in your eyewear may be necessary to maintain clear and comfortable vision.

 

Spots and Floaters

Spots (often called floaters) are small, semi-transparent or cloudy specks or particles within the vitreous, the clear, jelly-like fluid that fills the inside of your eyes. They appear as specks of various shapes and sizes, threadlike strands or cobwebs. Since they are within your eyes, they move as your eyes move and seem to dart away when you try to look at them directly.

Spots are often caused by small flecks of protein or other matter trapped during the formation of your eyes before birth. They can also result from deterioration of the vitreous fluid, due to aging; or from certain eye diseases or injuries.

Most spots are not harmful and rarely limit vision. But, spots can be indications of more serious problems, and you should see your optometrist for a comprehensive examination when you notice sudden changes or see increases in them.

By looking in your eyes with special instruments, your optometrist can examine the health of your eyes and determine if what you are seeing is harmless or the symptoms of a more serious problem that requires treatment.

 

Strabismus/Crossed-eyes

Crossed-eyes, or strabismus, occurs when one or both of your eyes turns in, out, up or down. Poor eye muscle control usually causes crossed-eyes. This misalignment often first appears before age 21 months but may develop as late as age six. This is one reason why the American Optometric Association recommends a comprehensive optometric examination before six months and again at age three.

There is a common misconception that a child will outgrow crossed-eyes. This is not true. In fact, the condition may get worse without treatment.

Treatment for crossed-eyes may include single vision or bifocal eyeglasses, prisms, vision therapy, and in some cases, surgery. Vision therapy helps align your eyes and solves the underlying cause of crossed-eyes by teaching your two eyes to work together. Surgery alone may straighten your eyes, but unless your eye muscle control is improved, your eyes may not remain straight.

If detected and treated early, crossed-eyes can often be corrected with excellent results.
20/20

20/20 vision is a term used to express normal visual acuity (the clarity or sharpness of vision) measured at a distance of 20 feet. If you have 20/20 vision, you can see clearly at 20 feet what should normally be seen at that distance. If you have 20/100 vision, it means that you must be as close as 20 feet to see what a person with normal vision can see at 100 feet.