Eye defects can develop over time or may be something a person is born with. They may be something that is able to be corrected or may lead to more serious problems such as blindness. The key is to recognize the symptoms of these disorders and get them corrected as soon as possible.
Myopia
More commonly known as nearsightedness, myopia is a condition that occurs when rays of light entering the eye focus in front of the retina rather than directly on it, according to the American Foundation for the Blind. This may occur for one of two reasons--either the power of the lens is too strong or the eyeball itself is too long.
Those who suffer from myopia are able to see objects that are close just fine, however objects at a distance, no matter how large, appear blurry to them. This usually requires them to squint to see these objects and can result in headaches or eye strain. Glasses tend to help correct this condition. In some cases, surgery is required.
While myopia in its simplest form does not usually lead to loss of vision, another clinical type, degenerative myopia, can. It is a more severe form of mypoia, is believed to be hereditary and is seen most frequently in people of Japanese, Chinese, Jewish and Middle Eastern descent, according to Macular Degeneration Support. It is the seventh leading cause of blindness, affecting approximately 2 percent of the United State's population.
Hyperopia
Just as some people are nearsighted, others are farsighted--this is what hyperopia refers to. Its effects are the opposite of myopia--people diagnosed with hyperopia can see objects from a distance without a problem but have difficulty with objects that are close to them. This is due to light rays entering the eye behind the retina, rather than on it. Its cause is either from an eyeball that is too short or a lens that is too weak. Again, it is a condition that can be corrected easily with either glasses or contacts. In severe cases, surgery may be required. If left untreated, it can lead to loss of vision.
Astigmatism
An astigmatism is a common eye defect, according to the American Foundation for the Blind, and is one that is present from birth. This defect does not allow the rays of light to enter the retina at any single point; some may come in or behind it, while others may focus directly on it. Those with this condition may see lines or forms in different ways--some may appear clear while others appear blurry. In most cases, glasses can correct the condition, or surgery may be required to correct it.
Diabetic Retinopathy
Diabetic retinopathy results from damage caused by diabetes; a person's chances of developing this condition increases the longer he suffers from diabetes, according to the American Federation for the Blind. The National Eye Institute states that diabetic neuropathy is the most common eye disease among diabetics and is the fourth leading cause of blindness among American adults. It occurs in four stages. Deprivation of blood to the blood vessels of the retina, which is due to loss of circulation caused by diabetes, is the main reason for this defect.
Those with type I and type II diabetes are at risk for this eye defect, and should undergo a dilated eye exam once every year to help prevent its progression. While 40 to 45 percent of diabetics have some stage of diabetic retinopathy, if detected in the earliest stage, the National Eye Institute states that the risk of blindness can be reduced by 95 percent with proper care and treatment. However, if left undetected and allowed to progress to one of the more serious stages, the risk of vision loss increases greatly.
