Cataract

A cataract is a progressive, painless clouding of the lens of the eye. Cataracts occur when protein builds up on the lenses and blocks some of the light from passing through, making it difficult to see clearly. Over time, cataracts can cause blindness. They're often related to growing older, but sometimes they can develop in younger people.  In a normal eye, light enters and passes through the lens. The lens focuses that light into a sharp image on the retina, which relays messages through the optic nerve to the brain. If the lens is cloudy from a cataract, the image you see will be blurry. Other eye conditions, such as myopia, cause blurry vision, too, but cataracts produce some distinctive signs and symptoms.

Blurry vision at any distance is the most common symptom of cataracts. Your view may look foggy, filmy, or cloudy. Over time, as the lenses become more clouded, less light reaches the retina. People with cataracts may have an especially hard time seeing at night. Another early symptom of cataracts is glare, or sensitivity to light. You may have trouble seeing in bright sunlight. Indoor lights that once didn't bother you now may seem too bright or have halos. Driving at night may become a problem because of the glare caused by oncoming headlights. Sometimes, cataracts can cause double vision (also known as diplopia). As the cataract grows larger, the double vision may go away.

Cataracts can affect your color vision, making some hues look faded. Your vision may gradually take on a brownish or yellowish tinge. At first, you may not notice this discoloration. But over time, it may make it harder to distinguish blues and purples. Sometimes, a cataract may temporarily improve a person's ability to see close-up, because the cataract acts as a stronger lens. This phenomenon is called second sight, because people who may have once needed reading glasses find that they don't need them anymore. As the cataract worsens however, this goes away and vision worsens again. Frequent changes to your eyeglass or contact lens prescription can be a sign of cataracts. This is because cataracts are progressive, meaning they get worse over time.

The majority of cataracts are related to aging.  Babies are sometimes born with cataracts, also called congenital cataracts, or children may develop them as a result of injury or illness. The exact cause of cataracts is unknown. While the risk grows as you get older, these factors may also contribute: Diabetes,Smoking,Excess alcohol use,Eye Injury,Prolonged use of corticosteroids,Prolonged exposure to sunlight or radiation

Most cataracts can be diagnosed with an eye exam. Your eye doctor will test your vision and examine your eyes with a slit lamp exam to look for problems with the lens and other parts of the eye. The pupils are dilated to better examine the back of the eye, where the retina and optic nerve lie. If your vision loss can't be corrected with glasses or contact lenses, you may need surgery to remove the cataracts. In cataract surgery, the cloudy lens is removed and replaced with an artificial lens. The surgery, which is done on an outpatient basis, is safe and extremely effective at improving vision. If cataracts are present in both eyes, surgery will be done on one eye at a time.

Complications from cataract surgery are rare. The most common risks are bleeding, infection, and changes in eye pressure, which are all treatable when caught early. Surgery slightly raises the risk of retinal detachment, which requires emergency treatment. Sometimes, the tissue around the IOL can become cloudy, even years after surgery. This "after-cataract" is corrected by using a laser to make a tiny hole in the capsule to allow light to pass through.

Things you can do to lower your risk of developing cataracts:Don't smoke.Always wear a hat or sunglasses in the sun.Keep diabetes well controlled.Limit alcohol consumption.