When we are born, the lens in the eye is normally crystal clear. When cataract forms, the lens becomes hazy, opaque or discolored. Cataract usually progresses over time, increasing the size or density of the opacity in the lens.

A small amount of cataract may not noticeably affect the vision, but more advanced cataract can cause blurred vision, glare and shadowing around objects. When cataract has impaired the vision to a certain degree, surgery can be performed to remove the lens from the eye and replace it with a plastic implant lens.

The main causes of cataract are exposure to UV in sunlight over your lifetime, and aging.

Cataract can occur as young as the 40s, however the likelihood of developing cataract increases steadily with age. The best way to protect your eyes from cataract development is to wear 100% UV-protected, wrap-around sunglasses when outside.

The interior of the eye produces a fluid, called aqueous, which is continually produced and continually drained. This fluid exerts outward pressure against the wall of the eye. The amount of fluid inside the eye determines the eye pressure, which is measured during your eye examination.

When the eye pressure is higher than the eye tissues can tolerate, it compresses the nerve inside the eye. Glaucoma results when this compression causes the nerve fibers to gradually die off. The pressure at which this damage occurs varies widely among individuals. If glaucoma is left untreated, there is progressive loss of peripheral vision, followed by loss of central vision. Treatments for glaucoma include drops that lower the eye pressure, laser treatment and surgery.

There are several different types and causes of glaucoma, but the majority of cases are of unknown cause, or are due to heredity or aging. Glaucoma can occur at any age, but is most common over the age of 40, with the likelihood of developing glaucoma increasing steadily with age.

There is no known way to prevent glaucoma from developing, and it has no symptoms. Therefore, early detection and treatment are critical to prevent the progression of glaucoma. It is important for all adults to have eye examinations at least every 2 years, to be tested for glaucoma.

Macular Degeneration

The macula is the area of the retina which provides central, detailed vision. There are 2 types of macular degeneration: dry and wet. The dry type is a breakdown of the retinal tissue in the macula, which is thought to be due to poor blood supply and an accumulation of waste products in this area. This causes a gradual loss of central vision, eventually making it more difficult to read, drive and see people's faces. The wet type is less common than dry, and usually occurs in an eye that already has dry macular degeneration. New blood vessels grow, and then break and bleed under the macula, causing a sudden, drastic loss of central vision.

The dry form of macular degeneration is currently not treatable. However, there is a specific formulation of vitamins which has been shown to slow the progression of the disease. There are several medical treatments available for wet macular degeneration, and it is important that treatment is started as soon as possible.

Macular degeneration can occur as young as the 50s, and is increasingly common with age. There are several factors that contribute to the development of macular degeneration, including heredity, smoking, poor diet, obesity and UV exposure. To decrease your risk of developing macular degeneration, do not smoke, eat a diet high in antioxidant vitamins and minerals, maintain your weight at a healthy level and wear 100% UV-protected, wrap-around sunglasses when outside.

For further information on macular degeneration, see AMD Alliance.