Vision problems are far more common than most people might think. Although it is difficult to know exactly just how many people in the United States wear eyeglasses, because there are so many different variables to consider, the Vision Council of America estimates that approximately 75% of all adults use some form of vision correction. Of these, about 64% wear eyeglasses and about 11% wear contact lenses, either exclusively, or in combination with glasses. In most of these cases, the problem is not the result of a serious eye disease or degenerative condition, like cataracts, glaucoma, or retinopathy, but is instead caused by what we call a simple refractive error, namely nearsightedness, farsightedness, or astigmatism. However, even though they are extremely common, many patients still don’t understand exactly how refractive errors work and all the options that are available for treating them.
The eye essentially works like a tiny camera. Light enters through a small, adjustable hole (called the pupil) and is then focused by an adjustable lens onto a screen of light-sensitive nerve endings that line the back of the eye, called the retina. For the anatomy of the eye to work properly, the distance between the lens and the retina must be exact, so that the light can be focused into a clear image. If the distance is either too great or too small, the light will converge too late or too early, and the image will appear fuzzy or distorted, resulting in a refractive error.
- Nearsightedness (or myopia) results when the eye is too large. The rays of light intersect too soon and then spread out again, making them out of focus when they reach the retina. The naturally flexible lens at the front of the eye can bring nearby objects into focus, but not objects that are far away. Approximately 30% of Americans suffer from nearsightedness.
- Farsightedness (or hyperopia) results when the eyes are too small. Rays of light from nearby objects do not have time to intersect before striking the retina, so only objects that are farther away can be seen clearly. The lens has to work harder to bring nearby objects into focus, so patients with severe cases of hyperopia can experience difficulty focusing at all ranges.
- Astigmatism is a more complicated condition that can occur in combination with both myopia and hyperopia. Instead of being perfectly spherical, the eyes of a patient with astigmatism are shaped like a football. This irregular shape distorts light as it passes through the lens so that it cannot focus on a single point. As a result, patients experience blurred vision at all distances.
The most common way to address refractive errors is by using a second lens, in the form of either eyeglasses or contacts, to help focus the light entering the eyes at the correct point. By taking detailed measurements of the eye, our consultative optometrist, Dr. Marc Lay, can determine exactly how the eyeglass or contact lens needs to be shaped in order to make the vision sharp. Not all lenses are created equal, but our on-site optical center offers specials on the most advanced lenses available. Finally, although not necessarily an option in all cases, some patients may also be able to take advantage of LASIK Eye Surgery, a quick and easy procedure where our board-certified ophthalmologist, Dr. William Segal, uses advanced laser technology to painlessly reshape the eye and permanently correct the refractive errors so that glasses will no longer be needed.
There are many different conditions can potentially affect your eyesight, but fortunately our team has nearly twenty years of experience treating them all. If you are concerned about your vision, please contact Georgia Eye Physicians and Surgeons so that you can make an appointment for a comprehensive medical eye exam. Don’t forget to follow us on Facebook, Twitter, and Google+ for more information on how to keep your vision clear and healthy.