By the time you turn 65, chances are about 50-50 that you will have begun to develop a cataract, a clouding of the clear lens that focuses light onto your retina. The lens is composed of water and proteins arranged to let light through with minimal distortion. With age, the proteins can clump together, letting less light through and blurring vision. You may also be at increased risk for cataract if you regularly take corticosteroids or the anti-cancer drug tamoxifen.
Can cataract be prevented?
Age is the major risk factor for cataracts. Other factors that affect risk include the following:
Tobacco. Smokers develop cataract earlier.
Alcohol. Alcohol consumption slightly increases the risk of cataract, and the more you drink, the greater the risk.
Sunlight. Long-term exposure to ultraviolet B rays from the sun can increase risk. Protect your eyes with sunglasses and a broad-brimmed hat.
Diet. There's some evidence that a well-balanced, low-fat diet with plenty of fruits and vegetables may help reduce your risk of cataracts.
Age-related cataracts start small, usually in the center of the lens, and may develop in one or both eyes. At first they cause no symptoms, but as they grow over months or years, problems such as blurring, glare, double vision, dull color vision, poor night vision, and worsening nearsightedness can make it frustrating to read and dangerous to drive.
Cataract surgery was once complicated and risky, so ophthalmologists usually waited until vision was severely limited before proceeding. Today, cataract surgery is one of the easiest, most common, and safest surgeries performed in the United States. You should consider it as soon as vision problems start to interfere with usual activities.
Preparing for surgery
The only way to get rid of a cataract is surgical removal of the cloudy or discolored lens and replacement with a clear artificial lens. Before surgery, your clinician will use ultrasound to evaluate the shape of your eye and calculate the strength of the replacement lens. Insurers consider these essential parts of the process and will cover the cost. Your clinician may also suggest other specialized eye exams to help predict the outcome of surgery; insurers regard many of these as experimental and do not provide coverage.
Tell your surgeon about all medications you're taking. If you have glaucoma, you may need to stop or change your eye drops temporarily. Let your surgeon know if you take an alpha blocker or have ever taken one. These drugs can interfere with the medications used to keep the pupils dilated during cataract surgery, so the surgeon may need to make adjustments to compensate.
Choosing your lenses
After the cataract is removed, the lens must be replaced. For most people, that means inserting an intraocular lens within the lens capsule at the time of surgery. Several types are available. The choice depends on the shape of your eye, other vision problems or eye diseases you may have, and your own preferences and priorities. Before surgery, you need to think about the type of lens best suited to your situation. Make sure your physician is aware of your usual daily activities and knows which of these you'd most like to perform without glasses. The options include the following:
Monofocal lenses. These lenses restore clear vision at a set distance. If you wear glasses or contacts for distance vision, your vision without glasses may be much improved after surgery. But you will need separate glasses for reading and perhaps also for intermediate distances (such as working at the computer or playing piano).
To eliminate the need for reading glasses, the surgeon can implant a distance lens in one eye and a close-up lens in the other (just as some people wear a different contact lens prescription in each eye).
Toric lenses. These are shaped to correct astigmatism and reduce the need for glasses to correct distance vision. You should see better without glasses, but some astigmatism may still remain.
Multifocal lenses. Like bifocals and progressive eyeglasses, multifocal lenses are designed to help with presbyopia, the age-related difficulty in shifting focus from far to near.
Multifocal lenses do not work well in people with much astigmatism and certain other eye conditions. The size of your pupil also matters. If your pupils are small, light won't get through the part of the lens that provides near vision; if they are very large, you'll notice more glare and haloes at night.
Accommodative lenses. These hinged lenses move in response to your eyes' focusing muscles, providing distance, intermediate, and near vision.
Medicare and most insurers cover cataract surgery, but not treatment of presbyopia, which is regarded as an elective procedure. If you choose to implant multifocal or accommodative lenses, Medicare will pay only the amount required for surgery and implantation of standard lenses. You must pay the remainder out of pocket, and some choices can cost thousands of dollars extra.
Unless you have a medical condition that warrants close observation in the hospital or makes it unsafe to recuperate at home, someone will drive you home after you leave the recovery room. Ask your clinician about permitted activities. You will probably be able to use your eyes within hours and resume all but the most strenuous activities within days. You will take antibiotics and use cortisone drops or ointment and nonsteroidal anti-inflammatory drops to prevent infection and reduce inflammation while your eyes heal.
Depending on which kind of lens you have implanted, you may see better immediately, or your vision may improve over several weeks. Possible complications include bleeding within the eye, glaucoma, and infection; you'll also always be at a slightly increased risk of a detached retina.
After about 30% of cataract operations, the lens capsule supporting the implant eventually becomes cloudy. This is sometimes called an after-cataract or secondary cataract. To remedy the problem, the ophthalmologist can drill a tiny hole in the capsule with a laser to let the light through. This is usually a quick and painless office procedure.
April 2007 update