Cataracts occur when the lens of the eye becomes clouded. The lens is a flexible, clear structure of the eye that changes shape to reflect light onto the retina. This allows your eye to focus light rays, transforming visual signals into a clear, sharp image.
As you get older, the tissue forming the lens grows less flexible, thicker, and less transparent. Slight degeneration of the tissue causes cloudy areas to form. As light passes through the lens, these cloudy areas scatter the rays and cause visual distortions. Many people report that having cataracts is like looking through a foggy windshield, as everything looks clouded. This can cause difficulties when driving, reading, and performing other everyday activities.
Age-related cataracts are the most common, but other types may also develop. Cataracts are associated with eye injuries, exposure to radiation, smoking, diabetes, steroid use, and surgery for other eye conditions. Cataracts can also be congenital, causing some babies to be born with cataracts.
Types of Macular Degeneration
The science of optometry and ophthalmology, classify macular degeneration into one of two types: dry or wet. Diagnoses can change from one type to the other. The difference between the types can best be remembered by associating "wet" with blood vessels.
Dry Macular Degeneration
This type of damage is the most common form, accounting for approximately 90 percent of macular degeneration diagnoses. Yellow-colored metabolic waste products known as drusen collect beneath the retina, causing a painless but progressive damage and cell death to retinal cells. This form of the disease usually progresses more slowly than does the wet form, however, its ultimate result can be devastating: sufferers may be left without any central version. Imagine a large dark "ball" blocking most of your site all of the time. Peripheral vision is all that may remain, markedly impairing or preventing normal activities of daily living such as driving, reading, watching television, cooking and any work that requires small, detail-oriented work.
Wet Macular Degeneration
Wet macular degeneration makes up only 10 percent of this condition's diagnoses but is the culprit in legal blindness 90 percent of the time. In this form of the disease, the body attempts to make up for the death of photoreceptors cells by growing new, but fragile, blood vessels behind the macula. Leaking blood vessels can further impair sight and cause permanent scarring of the macula. Symptoms of the damage are similar to that of dry macular degeneration, however, its progress can take place rapidly.