Slideshow Pictures: Cataracts -- A Visual Guide to Causes, Symptoms and Surgery
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What Are Cataracts?
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.
How Cataracts Affect Your Vision
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.
Cataract Symptom: Blurry Vision
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.
Cataract Symptom: Glare
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.
Cataract Symptom: Double Vision
Sometimes, cataracts can cause double vision (also known as diplopia). As the cataract grows larger, the double vision may go away.
Cataract Symptom: Color Changes
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.
Cataract Symptom: Second Sight
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.
Cataract Symptom: New Prescription
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.
Who Gets Cataracts?
The majority of cataracts are related to aging. More than half of Americans over 65 have cataracts. Babies are sometimes born with cataracts, also called congenital cataracts, or children may develop them as a result of injury or illness.
What Causes Cataracts?
The exact cause of cataracts is unknown. While the risk grows as you get older, these factors may also contribute:
- Excess alcohol use
- Eye Injury
- Prolonged use of corticosteroids
- Prolonged exposure to sunlight or radiation
How Are Cataracts Diagnosed?
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.
Surgery for Cataracts
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.
Types of Cataract Surgery
There are two types of cataract surgery. In the more common type, called phacoemulsification, or phaco, the doctor makes a tiny incision in the eye and breaks up the lens using ultrasound waves. The lens is removed, and an artificial lens (called an intraocular lens, or IOL) is put in its place. In extracapsular cataract surgery, the doctor makes a larger incision and removes the cloudy part of the lens in one piece.
Cataract Surgery Innovations
One recent development in cataract surgery is the multifocal IOL, which can correct both near and distance vision. Conventional “monofocal” lenses only correct for distance vision, meaning reading glasses are still needed after surgery. Other “premium” implants are available to correct presbyopia, myopia, and astigmatism. A lens for better color vision is in development (shown here next to a dime.) An experimental laser cataract surgery is also showing promise, giving more accurate results with a less invasive procedure.
What to Expect After Surgery
For a few days, your eye may be itchy and sensitive to light. You may be prescribed drops to aid healing and asked to wear an eye shield or glasses for protection. It'll take about eight weeks for your eye to heal completely, though your vision should begin to improve soon after surgery. You may still need glasses, at least occasionally, for distance or reading -- as well as a new prescription after healing is complete.
Cataract Surgery Risks
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.
Should You Have Cataract Surgery?
Whether or not to have cataract surgery is up to you and your doctor. Occasionally cataracts need to be removed right away, but this isn't usually the case. Cataracts affect vision slowly over time, so many people wait to have surgery until glasses or contacts no longer improve their vision enough. If you don't feel that your cataracts are causing problems in your day-to-day life, you may choose to wait.
Tips to Prevent Cataracts
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.
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