When discussing your vision, it is worth noting that your ability to see continually changes as you age. Most infants are hyperopic (farsighted) and more adults are myopic (nearsighted). In between lies a broad spectrum for you to be in. Much of this has to do with the shape of your eyeball. The type of correction that you will need depends on the deviation of your eye. These deviations also determine whether you are a candidate for glasses, contacts, or surgical corrections for your vision.
Myopia (Nearsighted):
In this condition, when you look at an object that is close to you it is clear but when you look at something far away it is blurry. Myopia usually begins around age 7 and can be seen many times when there is rapid growth. Frequently, routine vision screenings at school will show this condition. For adults, a problem with observing signs while driving, movie or TV screens, or events on the playing field may indicate myopia and a need for correction. Correction of this problem is usually with glasses, contacts, and/or laser vision correction.
Hyperopia (Farsighted):
Hyperopia is the medical term for “farsightedness.” Hyperopia occurs when your eye is too short in relation to the curvature of your cornea. Light rays entering your eye focus behind the retina, producing a blurred image. Some farsighted people can use their focusing muscles to pull the image forward onto the retina, allowing them to see clearly. But others, who cannot overcome the effects of hyperopia, need reading glasses or bifocals.
Astigmatism:
Many patients with myopia and hyperopia have some degree of astigmatism, or an oval shape, to their cornea. It occurs when your cornea is shaped more like a football than a basketball. As a result, you experience distortion or tilting of images due to the unequal bending of light rays entering your eyes. People with high degrees of astigmatism have blurred vision for both near and distant objects. Correction of this problem is usually with glasses, contact lenses, or in some cases, laser vision correction.
Presbyopia:
Presbyopia is part of the normal process of aging and is not corrected with the laser vision corrections available today. It develops as the lens of the eye loses some of the flexibility that characterizes a younger eye. Everyone experiences the effects of presbyopia, typically between the ages of 40 and 50. Patients who become presbyopic may require bifocals in their forties, and those who never needed glasses before may require reading glasses.