Myopia or nearsightedness is a refractive condition in which near objects are seen clearly while distant objects are blurred. There are many optical elements in the eye; the cornea, the lens, and the fluids between them. These all combine in such a way to image the outside world onto the back of the eye, or retina.

Infants are typically born farsighted and over the first 2 years of life, the optical elements of the eyes change until a slightly farsighted (hyperopic) refractive error or no refractive error (emmetropia) remains. Later in life myopia can develop if the eyeball becomes too long and objects come to a focus in front of your retina. Since the eyeball can not be shortened the optics are changed coming into the eye so that light comes to a focus on the retina. This is done with glasses, contact lenses or by manipulating the shape of the cornea through refractive surgery or a procedure utilizing contact lenses, called orthokeratology.

About 25% percent of the general population in the U.S. are nearsighted. While it was once believed that myopia was inherited, recent evidence suggests that there are both genetic and environmental influences. For instance, myopia is found more often in identical twins than fraternal twins suggesting a strong genetic influence. Yet indicators of environmental influences are the higher incidences of myopia in urban vs. rural communities, in graduate or professional degree students vs. high school or college graduates, and in certain occupations that require a lot of near work, such as clinical microscopy.

Myopia rarely develops before 6 years of age, more commonly it occurs at about age 10 years of age. However, some people don’t develop myopia until their 20’s, often when they enter college or graduate school. On occasion some people first develop myopia in their 30’s and even in their 40’s. In addition, some childhood myopes stop progressing by age 18 while others continue into their 20’s, 30’s and 40’s.

It is still unknown why some people develop myopia while others do not, why it first occurs at different ages and why some progress while others stabilize. What is known is that both environment and hereditary play a role. At the Eye Care Clinic, various treatment options are offered which have promise for slowing down myopic progression. We are involved in clinical studies that are researching the above questions (CLEERE) and in projects that are testing the newest medical treatment options to slow down myopia progression. (CAMPP)

Hyperopia or farsightedness occurs when the eyeball is too short or the cornea has too little curvature, so that light entering the eye is focused behind the retina. While focus is required to see near objects clearly, persons with a hyperopic refractive error also have to focus for far objects. Thus, by using the focusing system some farsighted people can see clearly without glasses. Often, they may not even know they are farsighted. However, if there is a significant amount of hyperopia, then the constant focusing will tire their eyes. They will have even more trouble with near work because of the extra work their eyes have to do. Hyperopia can be corrected with glasses, contact lenses, and cornea reshaping techniques such as refractive surgery which focuses the light rays onto the retina.

Most infant eyes start out hyperopic and become emmetropic (no refractive error or slightly hyperopic refractive error) at about age 2 years. It is normal to have a small amount of hyperopia. It is likely that the visual environment in those first 2 years of life allows the fine tuning necessary for the eye to become emmetropic. However, large amounts of hyperopia in infancy often result in a continued hyperopic refractive error later in life.

Usually all the hyperopia a person will have in their lifetime is the hyperopia they have as a 5-year-old child. Hyperopia rarely progresses. However a hyperopic person may need stronger glasses as they get older. This is because as we age, our focusing system becomes less efficient and therefore harder to rely on it as much to see clearly without the use of corrective lenses.

Some children are farsighted and don’t know it. They don’t realize that they are working harder than others just to get things clear. Unfortunately, school screenings often fail to detect farsightedness. Children with uncorrected hyperopia may avoid near work or do poorly at near work related tasks. Common signs of farsightedness include difficulty in concentrating and maintaining a clear focus on near objects, eyestrain, fatigue and/or headaches after close work, aching or burning eyes, irritability or nervousness after sustained concentration. All children should have a vision examination before starting school. (Pediatric Vision Examinations)

Astigmatism is a vision condition that occurs when the surfaces of the cornea, the front part of the eye and/or the lens are not exactly spherical or perfectly round. This results in preventing a perfect focus on the back of the eye. With astigmatism, vision may be blurred at all distances. If the astigmatism is mild, blur may not be noticed. However, headaches, or sore or tired eyes may be a symptom of uncorrected astigmatism. With more severe astigmatism vision will be noticeably blurred.

Almost all levels of astigmatism can be optically corrected with eyeglasses and/or contact lenses. Corneal modification through orthokeratology or refractive surgery is also a treatment option for some patients.

Presbyopia is a vision condition in which the crystalline lens of the eye becomes sclerotic or hard. Without its flexibility, it becomes difficult to focus on close objects. Presbyopia usually becomes noticeable in the early to mid-forties. In cases of hyperopia it may occur earlier. Presbyopia is a normal process of aging. Some signs of presbyopia include the tendency to hold reading materials farther away than usual, blurred vision at a normal reading distance, eye fatigue and possibly headaches after doing close work. In the beginning, only a prescription for near work, like reading may be needed. In time, a prescription for the intermediate distance, like for computer work may be needed as well. After about age 60 years most have reached the full prescription for presbyopia. Yet there still may be some changes in the prescription after that because of other changes in the lens. There are many treatment options for presbyopia including bifocals, trifocals, progressive lenses and contact lenses. We will discuss which option bests suits your visual needs.

In addition to the age-related hardening of the crystalline lens that causes the loss of focusing ability, the lens also becomes more opaque and yellow. This normal process of aging is the formation of a cataract, and will lead to noticeable loss of clarity. We can evaluate the degree of the cataract and discuss appropriate treatment options such as cataract surgery.