Cataracts - Symptoms
Cataract development is usually a gradual process of normal aging, but can occasionally occur rapidly.
Many people are in fact unaware that they have cataracts because the changes in their vision have been so gradual. Cataracts commonly affect both eyes, but it is not uncommon for cataracts in one eye to advance more rapidly. Cataracts are very common.
Cataracts are usually gradual and usually not painful or associated with any eye redness or other symptoms unless they become extremely advanced. Rapid and/or painful changes in vision are suspicious for other eye diseases and should be evaluated by an eye-care professional.
Eye-care professionals may mention during a routine eye exam that you have early cataract development even if you are not yet experiencing visual symptoms.
Although your doctor will be able to tell when you first begin to develop cataracts, you will generally be the first person to notice changes in your vision that may require cataract surgery. Clouding of the lens may start to be seen at any age, but it is uncommon before the age of 40. However, a large majority of people will not begin to have symptoms from their cataracts until many years after they begin to develop.
Since cataract development rarely causes any long-term damage to the eye, cataract surgery should be considered only when visual symptoms begin to develop. Whenever significant vision problems are noted, you should schedule an exam by an eye-care professional. Typical symptoms may include blurry vision, difficulty with glare or night vision, poor color vision, or frequent changes in eyeglass prescription.
For an early cataract changes, vision may be improved by simply changing your eyeglass prescription, using a magnifying lens, or increasing lighting when you do visually demanding tasks. Eventually, cataracts get to a point where the only effective intervention is surgery. This decision is made based mainly on the degree of visual limitation the patient is experiencing.
Not all cataracts impair vision or affect daily living. For those that do, common symptoms include:
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.
Improvement of near vision (second sight) that then gets worse.
Difficulty doing daily activities because of vision problems.
What Causes Cataracts?
The lens inside the eye works much like a camera lens, focusing light onto the retina for clear vision. It also adjusts the eye's focus, letting us see things clearly both up close and far away.
The lens is mostly made of water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it.
But as we age, some of the protein may clump together and start to cloud a small area of the lens. This is a cataract, and over time, it may grow larger and cloud more of the lens, making it harder to see.
No one knows for sure why the eye's lens changes as we age, forming cataracts. But researchers worldwide have identified factors that may cause cataracts or are associated with cataract development. Besides advancing age, cataract risk factors include:Ultraviolet radiation from sunlight and other sources
Prolonged use of corticosteroid medications
Statin medicines used to reduce cholesterol
Previous eye injury or inflammation
Previous eye surgery
Hormone replacement therapy
Significant alcohol consumption
One theory of cataract formation that's gaining favor is that many cataracts are caused by oxidative changes in the human lens. This is supported by nutrition studies that show fruits and vegetables high in antioxidants may help prevent certain types of cataracts (see below).
If you think you have a cataract, see an eye doctor for an exam to find out for sure.