Bad eyesight is usually caused by three primary conditions: short sightedness, long sightedness, and astigmatism. These three conditions can usually be corrected with prescription eyeglasses or contact lenses. In some cases, depending on the overall health of the individual, and the severity of the condition, eye surgery may also be an option.
Short sightedness is an eye condition that causes the patient to be able to see things that are close up, but have diminished capacity in their long range vision. This type of bad eyesight is also referred to as myopia, and is considered the most common eye disorder. It can usually be corrected with prescription eye wear or surgical procedures.
Some people are able to see things in clarity that are at a distance, but cannot focus on objects near to them. This type of condition is called longsightedness or farsightedness, or hypermetropia. Sometimes this condition worsens with age, and is the most common type of vision problem in people over the age of 40. Presbyopia is a condition that is similar to longsightedness, and is also considered age-related. Sufferers of presbyopia typically only need prescription eye wear to help them read small print.
Macular degeneration is a type of eye disease that is the root cause of many cases of bad eyesight. There are two types of macular degeneration, referred to as “wet” or “dry” degeneration. Dry generation is the result of loss of tissue in the retina of the eye. Wet macular degeneration is believed to be caused by leakage of blood vessels in and around the retina. Both types of macular degeneration are considered age-related vision impairments.
Another type of eye condition that is a common cause of bad eyesight is called astigmatism, a condition that is related to the shape of the eyeball itself. Normally, eyes are round in shape, but people who suffer from astigmatism have eyeballs that are shaped more like a football. This shape causes reflective problems that usually interfere with both long-range and short-range vision. People with this condition frequently have problems with vision even when they are very young children, as the condition is generally present at birth. Astigmatism can typically be corrected with prescription eye wear.
Other causes for bad eyesight could include loss of vision caused by diabetes, cataracts, and glaucoma. Cataracts and glaucoma are both much more common in elderly people, though they can occur in any age group. Cataracts are growths on the surface of the eyeball, and can usually be removed by surgery. Medical research has not yet found a way to reverse glaucoma. In some cases, it can lead to blindness.
