Cataract
A cataract forms when proteins in the lens of the eye clump together an cause a cloudiness in the lens which blocks light and interferes with vision. Cataracts begin to form in everyone over age 30 but they progress at different rates in individuals. The prevalence of cataracts increases with age as show in the graph below. A cataract can't spread from one eye to the other, although many people develop cataracts in both eyes.
People with cataracts experience a painless, progressive loss of vision
that may involve one or both eyes. Initially, cataracts may be small and
not affect vision. Over time the cataract can enlarge and vision becomes
dull and blurry as less light enters the eye (see comparison of vision
in photos below). A mature or "ripe" cataract refers to a lens
that is totally opaque or white.
Some of the changes that cause a cataract to develop in the lens of the
eye are related to overexposure to the sun or direct injury to the eye.
Other risk factors for cataracts include smoking and taking certain drugs
such as corticosteroids.
Risk Factors for Cataracts
- Age
- Trauma
- Intraocular disease
- Diabetes
- Medications (e.g., steroids)
- Exposure to sunlight
- Smoking
- Diet low in anti-oxidants
Treatment
Surgical extraction is the only way to reverse the progressive visual loss associated with a cataract. Cataract surgery is one of the most common procedures performed. It is safe and effective. Cataracts can be removed through either of the following procedures
- Phacoemulsification. A small incision is made on the side of the cornea, the clear surface that covers the front of the eye. A probe is inserted into the eye and ultrasound waves are emitted to soften and break up the cloudy center of the lens so it can be removed by suction.
- Extracapsular surgery. In this procedure, a slightly longer incision on the side of the cornea and removes the hard center of the lens. The remainder of the lens is removed by suction.
Usually an intraocular lens (IOL), a clear, artificial lens, is inserted and becomes a permanent part of your eye. Those with eye problems who are unable to an IOL need to use a soft contact lens or strong magnifying glasses.
Prevention
You can reduce your risk for cataract by wearing sunglasses that block ultraviolet (UV) light when you are outside in the sun and wearing protective goggles when engaging in activities with a high risk for eye injuries (e.g. racquet sports, using power tools). Eating a diet high in antioxidants (e.g., beta carotene, vitamin C) may lower risk for cataracts.
