WHY WE WEAR GLASSES

Normal Eye

The eye is like a camera. When you take a picture the lens in the front of the camera allows light through and focuses that light on the film that covers the back inside wall of a camera. When the light hits the film, a picture is taken. The eye works in much the same way. The front of the eye is clear and allows light to pass through. The light is then focused on a thin layer of tissue called the retina, which covers the back inside wall of the eye. When the focused light hits the retina an image is obtained. When the structures of the eye are perfectly coordinated, the light rays entering the eye come to focus directly on the center part of the retina producing normal vision, which is commonly referred to as 20/20 vision.

Myopia

Myopia is the most common refractive condition and affects one in four people in North America. Myopic individuals are nearsighted: they see near objects clearly but distant objects are blurry. Myopia can be due to either a steeply curved cornea or an elongated eye causing light rays to be focused in front of the retina instead of directly on it. The tendency to develop myopia runs in families. It usually starts in childhood and typically stabilizes in the late teens or early adulthood. Myopia is particularly well suited to correction by LASIK, or Laser Refractive Surgery.

Hyperopia

In hyperopia, or farsightedness, the eye is either too short or the cornea too flat. Light rays entering the eye are focused behind the retina rather than on the retina itself. In hyperopia close objects are usually blurry. As patients age, distant vision is also affected. More than 44 million Americans over the age of 40 are hyperopic. There is a new type of laser treatment to correct some degrees of hyperopia.

Astigmatism

Astigmatism is a refractive error in which distorted vision is caused by uneven curvature of the cornea. The cornea is irregular in shape causing light rays to focus at multiple points rather than a single spot on the retina. This results in blurred or double vision at all distances. Astigmatism affects 35% of the population and can sometimes be the result of scarring from disease or trauma. Most types of astigmatism can be corrected with contact lenses, and some degree of astigmatism can be corrected with Laser Refractive Surgery.

Presbyopia

When you are young, the lens in your eye is flexible. Your eye changes the shape of your lens easily, allowing you to focus on objects both close and far away.

As you grow older, your lens becomes less flexible. By age 40, the lens cannot change shape as easily as it once did and it is more difficult to read. This perfectly normal condition is called presbyopia.