Refractive errors are the most common vision disorders and can be corrected easily by wearing eyeglasses or contact lenses or sometimes through refractive surgery. When a refractive error is present, light entering the eye is not focused, resulting in a blurry image. The four most common refractive errors are:
- Nearsightedness, or myopia, is a refractive error characterized by the ability to see objects that are nearby clearly, while objects further away appear blurry.
- Hyperopia, also called farsightedness, is characterized by the inability to clearly see objects nearby without the help of corrective lenses.
- Astigmatism is a very common vision condition and often present in people who also have myopia or hyperopia. According to the American Optometric Association, astigmatism is due to either an irregular shaped cornea or the curvature of the eye’s lens, both of which prevent light from focusing properly on the retina, resulting in blurred vision at any distance. Most people have some degree of astigmatism, although the presence of a slight degree of the condition usually does not affect vision and usually will not require treatment. A larger degree of astigmatism, however, may need to be corrected as it can cause distorted or blurred vision, eye discomfort and headaches. Fortunately, astigmatism is easily corrected with lenses.
- Presbyopia affects nearly every adult as they age. As your eyes get older, their lenses gradually lose their ability to flex, making focusing on close objects, such as a page of a book, a newspaper, or a menu, difficult. It is a natural sign of aging and cannot be prevented, but it can be corrected through the use of reading glasses. Most people notice signs of it in their late 40s and early 50s.
In most cases, the conditions described above can be resolved and accurate vision restored easily with corrective eyewear. Corrective lenses work by bending light, either inward or outward as prescribed by an eye care provider, before it reaches the eye’s lens, allowing the eye to focus properly on the image.
Shared from The Vision Council