What are Cataracts?

Simulated vision with a Cataract

A cataract is a clouding of the normally clear natural lens in your eye, which lies behind the iris and the pupil. When the clear lens becomes milky or dirty looking, it is called a cataract. Though painless, cataracts can blur your vision by restricting the amount of light that enters your eye. Cataracts can occur in either one or both eyes, but do not spread from one eye to the other.

Cataracts start out with mild clouding and get cloudier over time. In the early stages, patients might not even be aware that they are developing a cataract. Some common symptoms of cataracts include:

• Cloudy or blurred vision
• Difficulty seeing at night
• Problems with glare, halos or light sensitivity
• Frequent changes in your eyeglass or contact lens prescription
• Double vision
• Colors seeming faded or yellowish
• Needing more light to read
• A new temporary ability to see up close without using reading glasses—often called "second sight"

The development of a cataract is generally part of the normal aging process; in fact, it is estimated that two-thirds of adults over 60 years of age have cataracts. Younger people, however, are also susceptible to cataracts. While early-stage cataracts can be treated with new glasses, magnifiers or other visual aids, cataracts eventually require surgery.

Cataract surgery is recommended when people feel their quality of life is affected and their ability to perform normal activities such as driving, reading or sports are compromised.