Is a vision condition in which near objects are seen clearly and distance objects appear blurry. Myopia is often inherited, but can also develop in someone with no family history of the condition. Typically myopia increases in degree during childhood and adolescence and will stabilize in early adulthood. Corrective glasses or contact lenses (including OrthoK) are required for clear vision.
Is a visual condition in which distance objects are normally perceived clearly, but close objects are more difficult to focus upon. The eye needs to "work hard" to compensate for long-sightedness. Glasses or contact lenses (including OrthoK) will relax the eyes and allow clear vision at all viewing distances.
Astigmatism is different from myopia and hyperopia as it affects vision clarity at all viewing distances. Astigmatism is most commonly due to the shape of the front surface of the eye (i.e., the cornea) being steeper in one direction than the other. This creates a shadow effect around objects, reducing the definition of vision. Astigmatism can be corrected by both glasses and contact lenses.
Occurs when the eye gradually loses its ability to focus at a normal reading distance as a result of a loss of elasticity in the crystalline lens inside the eye. It occurs predictably in everyone as a function of age, and is usually first noticed between the ages of forty and fifty years. The condition can be corrected with single vision reading glasses or multifocal spectacles, as well as bifocal contact lenses.