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Cataracts are a common eye condition in which the lens inside your eye becomes cloudy, causing blurry vision. Most people over 60 years of age develop some degree of cataracts. In many parts of the world, cataracts are a primary cause of avoidable blindness.
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Behind the iris (the colored part of your eye) sits the crystalline lens, which is a clear structure that helps your eye focus light. Zonule fibers attach the lens to the ciliary muscle, which controls the curvature of the lens.
When you read something up close, the lens becomes more rounded, allowing your eye to increase focus. When you look far away, the lens flattens out, allowing your eye to relax focus.
Early on in life, the lens is very flexible, allowing the ciliary muscle to easily control the lens. Over time, the natural aging process causes the lens to stiffen and thicken. Presbyopia, the loss of ability to see at near, occurs when the ciliary muscle has trouble flexing the stiffened lens. This process usually begins after age 40.
Over time, the proteins inside the lens also start to break down in a process called oxidation. Oxidation causes the lens to turn yellow and cloudy.
The crystalline lens is structured in multiple layers, much like an onion. Cataracts can form in the various layers, and you may have a combination of different types of cataracts. The three most common forms of age-related cataracts are:
Cataracts can form for other reasons besides age. They may be related to factors such as:
In many cases, mild cataracts do not cause any symptoms. Once cataracts start to progress, you may notice symptoms including:
Not all cataracts need to be removed. If the cataract is mild and your vision is clear, most doctors will simply monitor your cataracts. If you develop symptoms, you can decide if you want to have them removed.
Cataract surgery is an outpatient procedure (does not require a hospital stay) and only takes about 20 minutes. Typically, the surgeon removes one cataract first. After your eye heals, they remove the cataract from your other eye, if necessary.
Cataract surgery involves a few general steps:
Laser-assisted cataract surgery is a modern technique that can replace some of the steps involved in removing the cataract. Instead of a surgical blade, the surgeon can use a laser to make an incision on your cornea. The laser can break up the cataract, which uses less energy and is less disruptive to the eye than phacoemulsification.
As we get older, many people become concerned with developing cataracts. These are some frequent questions regarding cataracts:
Yes, once your cataracts are removed, they do not grow back.
However, a small percentage of people develop posterior capsular opacification after surgery. This condition is also called a secondary cataract or after-cataract. However, this opacification is not a new cataract. A posterior capsular opacification is a clouding of the membrane that is left in place during cataract surgery. This membrane is called the lens capsule and helps support the lens implant.
If enough clouding occurs, you may experience blurry vision. The eye surgeon can perform a procedure called posterior capsulotomy to restore your vision. This is a quick and painless treatment in which the surgeon uses a laser to create an opening in the lens capsule.
There is no proven regimen to prevent age-related cataracts. However, you may be able to slow down the progression of cataracts by:
Cataracts form at different rates, so it is hard to predict how soon you may need surgery. Progression also depends on the type of cataract you have. Some cataracts develop over several years, or even decades. Other cataracts grow rapidly, over a few months.
Your health and lifestyle also have an impact on cataracts. For example, if you have diabetes or spend most of your day working outdoors, you may be more likely to develop cataracts.
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