Saving Your Sight : Cataracts

by Food and Drug Administration (FDA)

(Page 3 of 4)

The Problem:

Cataracts are areas that distort light as it passes through the lens of the eye (opacities). The most common type of cataract is age-related. As we get older, protein in the lens of our eyes can clump together and cloud the lens, which is located behind the iris and the pupil. The lens is responsible for focusing light and producing sharp images.

Cataracts form slowly and typically cause no pain. In late 2000, David Guillot, 65, a retired aerospace engineer from Covington, La., noticed blurry vision. "I couldn't make out road signs even with my glasses on," he says. Shortly after, he was diagnosed with cataracts in both eyes. In addition to blurriness, common symptoms of cataracts are reduced night vision, problems with glare, frequent eyeglass prescription changes, impaired depth perception, and color distortion. Cataracts usually occur in both eyes.

Risk Factors:

Anyone can get cataracts, but it's for those over 60 that cataracts are most likely to interfere with vision. Cataracts can result from natural aging of the lens, but also can occur as a result of eye injury. An eye exam at least every two years is recommended for those over 60.

Some studies suggest that exposure to bright sunlight over several years may lead to cataracts, while other studies refute this, says Walter J. Stark, M.D., professor of ophthalmology at The Johns Hopkins University School of Medicine in Baltimore and director of the corneal and cataract services at the Wilmer Eye Institute. "The recommendation is that if one is outside a lot, say because of occupation, it may help to wear sunglasses that block ultraviolet rays," Stark says. "It won't hurt." Your sunglasses should offer 100 percent or nearly total UV protection. Wide-brimmed hats can also help block sunlight.

People with diabetes are at higher risk for cataracts, and smoking is a suspected risk factor. "It appears that smoking generally makes things worse when it comes to the eyes," Stark says. Taking corticosteroids for other medical conditions also can cause cataracts.

It had been believed that certain vitamins, such as vitamin C, might affect cataracts, but recent research has shown that nutritional supplements do not appear to prevent cataracts or keep them from getting worse.

Treatment:

For some people with cataracts, a stronger eyeglass prescription may be all that's needed. Keep up with regular eye appointments and talk with your doctor about how the cataracts affect your ability to work, read, and take part in other routine activities.

When cataracts interfere with daily activities, surgery may be recommended to remove the clouded lens and replace it with a new, artificial one. Monica says it's probably the most satisfying operation for an eye doctor and patient. Cataract surgery has an overall success rate of about 98 percent. According to NEI, it's the most frequently performed surgery in the United States, with over 1.5 million cataract surgeries performed each year.

Like any eye surgery, there are risks such as eye infection and swelling. "Cystoid macular edema is an uncommon complication of cataract surgery that causes swelling and blurry vision," says FDA's Berman.

The most common complication is formation of a secondary opacification (known as posterior capsular opacification) behind the new lens implant, Berman says. "This is treated with a laser that creates an opening through which clear vision is regained."

Just 10 years ago, cataract surgery required a hospital stay of several days. Now, the surgery can sometimes be done in less than 30 minutes on an outpatient basis. Guillot says his surgery took about 20 minutes and he went home that day. He had a cataract removed from one eye in June 2001, and had eye surgery on the second eye about three weeks later. His doctor broke up his cataracts with a high-frequency ultrasound. "I can see much better," Guillot says. "I can read the newspaper, watch TV, and I notice a big difference when I'm on the Internet. Sometimes I don't even need my glasses."

Advances in lens technology have improved cataract surgery over the last several years. "New lens materials, such as soft silicone, acrylic, and hydrogels, are more flexible and foldable," Berman says. "They permit surgery through smaller incisions and some appear to have lower rates of secondary opacification formation." And multifocal lens designs have been approved that provide both distance and near vision, so that reading glasses may not always be necessary. "Future advances might come," Berman says, "as a result of research on lens materials able to form a new lens within the eye itself."

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.