More commonly known as lazy eye, amblyopia is a childhood condition in which vision does not develop properly in one eye. If this condition is left untreated, it may result in permanent vision impairment because the child’s brain will disregard the image coming from the ill-seeing eye as the child’s brain matures, relying instead completely on the eye that sees clearly. Because of this, it is extremely important to have a child’s amblyopia regularly tested and treated. Amblyopia usually results because one eye focuses significantly better than the other. This discrepancy in focus ability is often due to severe nearsightedness or significant astigmatism. In some cases, strabismus (an ocular misalignment in which one eye turns inward or outward) is what causes the amblyopia. Strabismus prevents the eyes from focusing in unison and often results in double vision. The vision that deviates from focus deteriorates over time because the child’s brain relies only on the eye with proper focus. In other cases, amblyopia results because light cannot properly enter the eye due to something such as a cataract. Treatment seeks to correct the underlying problems causing the amblyopia and then to train the brain to start using the weak eye by placing an eye patch over the good eye. Although it will be difficult to see out of the weak eye at first, it will eventually improve the weak eye’s vision. Often, eyeglasses also help children to focus. Treatment options also include surgery in some cases in order to treat the underlying causes of the amblyopia.
Astigmatism is a common eye condition that has to do with the shape of the eye. Astigmatism occurs whenever the eye is not completely round. Because the eye is not perfectly round when astigmatism is present, light is refracted more in one direction than another when it enters the eye. Therefore, the eye is only able to focus on one part of an object at a time. Vision at any distance may appear blurry as a result. Although the exact cause of astigmatism is unknown, it is a common and naturally occurring condition. Symptoms include blurred vision, fatigue, and eyestrain. Corrective lenses, contact lenses, and refractive surgery can all be used to treat astigmatism.
Computer Vision Syndrome
A group of eye and vision problems that result from extended, uninterrupted focusing of the eyes on a computer display. Symptoms include blurred vision, headaches, dry eyes, eyestrain, neck pain, fatigue, redness in eyes, vertigo, difficulty refocusing eyes, and double vision. This condition is common and can usually be alleviated through regular eye care. Often, treatment includes a change to current corrective lens prescription or the addition of glasses prescribed specifically for computer use. There are also several important lifestyle factors that help prevent and reduce the symptoms of computer vision syndrome. These include positioning the computer screen four to five inches below eye level, making sure the computer monitor is free of glare, positioning your seat so that you are sitting upright and comfortable, and taking short breaks from looking at the computer screen every two hours.
Emmetropia is a term used to describe perfect vision. It derives from the Greek word “emmetros” which means “fitting” or “well-proportioned”. When the cornea and the crystalline lens (the two refractive structures of the eye) bend light correctly as it enters the eye, a clear image is produced on the retina. In this state of perfect vision, the eye lens remains in a relaxed and neutral state. The aim of corrective ophthalmologic surgery such as LASIK is to achieve emmetropic vision.
Hyperopia is better known as farsightedness. Farsightedness is a condition in which people see things in the distance clearly, but have difficulty viewing objects that are close. Farsightedness occurs when light does not focus directly on the retina because the eyeball is either too short, the cornea is curved improperly, or because the lens is positioned farther back than normal in the eye. Symptoms of farsightedness include blurred vision, headaches, trouble seeing up close, eyestrain, and trouble reading. It often starts in childhood and runs in families. Treatment options include eyeglasses, contact lenses, and refractive surgery.
A condition in which the structure of the cornea is not strong enough to maintain the round shape that it is supposed to. The cornea is the centrally located clear section of the eye’s surface. Normally, the cornea maintains a round shape. Keratoconus occurs when the collagen fibers that hold the cornea’s shape become weak. Since the fibers cannot hold the cornea in place, it becomes more and more cone-shaped over time. Symptoms of keratoconus include sudden changes in the vision of one eye, lights streaking, distorted perception of objects both near and far, and double vision when looking through one eye. This condition can be treated with both eyeglasses and contact lenses. In more moderate cases, contact lenses treat the condition more effectively than eyeglasses do. A cornea transplant is also a treatment option, but only in the most severe of cases.
Myopia (which is better known as nearsightedness) is an eye disorder in which people have difficulty seeing distant objects. Although distant vision is blurry, people with myopia usually have no difficulty seeing objects that are close. Nearsightedness occurs because the eyeball is misshaped. When light enters the misshaped eye, images do not focus directly on the retina and vision appears blurry. Nearsightedness usually runs in families and appears during childhood. Symptoms include blurry vision, headaches, eyestrain, and fatigue. Corrective eyeglasses and contact lenses are used to treat myopia. Refractive surgery is also a treatment option. Common refractive surgeries include LASIK and PRK (photorefractive keratectomy).
Presbyopia occurs commonly in adults over 40 years old. It is not a disease. Rather, it is part of the eye’s natural aging process. It refers to difficulty seeing objects up close and results from a loss in the ability of the eye to change its focus to objects that are near. Symptoms include the tendency to hold objects farther away in order to read them, headaches from doing work that is close up, and blurry vision at what is considered a normal reading distance. Although it cannot be cured, prescription glasses and contact lenses can be used to treat the effects of presbyopia.
This condition is more commonly known as “crossed eyes”. It is a condition in which the eyes do not look toward an object in unison. Instead, the eyes focus in different directions. The inability of the eyes to move in unison may occur only some of the time or all of the time. When people are born with eyes that do not align properly, it is called congenital strabismus. It many cases, there is no known cause. In other cases, congenital strabismus occurs as a result of either a nervous system problem or a tumor. Strabismus that presents in adults usually causes double vision. Strabismus in adults (especially those who did not have it as a child) may be the sign of a stroke or other serious condition. Because of this, adults should seek medical attention immediately in the even that their eyes suddenly misalign. Treatment for children with strabismus is incredibly important, for it is used to avoid amblyopia (lazy eye). Treatment includes various types of vision therapy. Surgery is also a treatment option and can be performed to either strengthen or weaken various muscles that move the eye.