A cataract is a clouding of the normally clear lens of your eye. For people who have cataracts, seeing through cloudy lenses is a bit like looking through a frosty or fogged-up window. Clouded vision caused by cataracts can make it more difficult to read, drive a car (especially at night) or see the expression on a friend's face.
Most cataracts develop slowly and don't disturb your eyesight early on. But with time, cataracts will eventually interfere with your vision.
At first, stronger lighting and eyeglasses can help you deal with cataracts. But if impaired vision interferes with your usual activities, you might need cataract surgery. Fortunately, cataract surgery is generally a safe, effective procedure.
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.
- Double vision.
- 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
- High myopia
- Family history
No studies have proved how to prevent cataracts or slow the progression of cataracts. But doctors think several strategies may be helpful, including:
Have regular eye examinations.
Eye examinations can help detect cataracts and other eye problems at their earliest stages. Ask your doctor how often you should have an eye examination.
Ask your doctor for suggestions about how to stop smoking. Medications, counseling and other strategies are available to help you.
Manage other health problems.
Follow your treatment plan if you have diabetes or other medical conditions that can increase your risk of cataracts.
Choose a healthy diet that includes plenty of fruits and vegetables.
Adding a variety of colorful fruits and vegetables to your diet ensures that you're getting many vitamins and nutrients. Fruits and vegetables have many antioxidants, which help maintain the health of your eyes.
Studies haven't proved that antioxidants in pill form can prevent cataracts. But, a large population study recently showed that a healthy diet rich in vitamins and minerals was associated with a reduced risk of developing cataracts. Fruits and vegetables have many proven health benefits and are a safe way to increase the amount of minerals and vitamins in your diet.
Ultraviolet light from the sun may contribute to the development of cataracts. Wear sunglasses that block ultraviolet B (UVB) rays when you're outdoors.
Reduce alcohol use.
Excessive alcohol use can increase the risk of cataracts.
If you think you have a cataract, see an eye doctor for an exam to find out for sure.