A cataract is a clouding that develops in the natural crystalline lens of the eye. The lens works much like a camera lens, focusing light onto the retina at the back of the eye. The lens also adjusts the eye’s focus, letting us see things clearly both up close and far away. The clouding can be varying in degree from slight to complete opacity and obstructing the passage of light. Early in the development of age-related cataract the power of the lens may be increased, causing near-sightedness (myopia), and the gradual yellowing and opacification of the lens. Cataracts typically progress slowly to cause vision loss and are potentially blinding if untreated. The condition usually affects both the eyes, but almost always one eye is affected earlier than the other.Cataracts are usually due to the aging process but can also be caused by eye trauma, heredity, diabetes, and even some medications. Currently, cataracts are the leading cause of preventable blindness worldwide.
- Cloudy, fuzzy, foggy or filmy vision
- Glare from lamps or the sun, which may be severe
- Difficulty driving at night due to glare from headlights
- Frequent changes in eyeglass prescription
- Double vision
- “Second sight” with temporary improvement in near vision (such as that needed for reading) in farsighted people
- Difficulty performing daily activities because of vision problems
Types of cataracts:
- In the nucleus called a nuclear cataract, forms in the center of the lens. This is generally caused by the natural aging process.
- At the cortex named the cortical cataract, forms around the edges of the lens and extends into the center. This is seen frequently in diabetics.
- At the back called a posterior subcapsular cataract, forms at the back of the lens. It can form for a variety of reasons including in people with diabetes or high farsightedness.