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 you get older, proteins in the lens of the eyes can clump together and cloud the lens. The lens, located behind the iris and the pupil, is responsible for focusing light and producing sharp images. Cataracts form slowly and typically cause no pain.
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 and Prevention
Anyone can get cataracts, but it's for those over 60 that cataracts are most likely to interfere with vision. An eye exam at least every two years is recommended for those over 60.
Cataracts can result from natural aging of the lens, but also can occur as a result of eye injury. Some studies suggest that exposure to bright sunlight over several years might 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.
"If someone is outside a lot, it may help to wear sunglasses that block ultraviolet rays," Stark says. 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 help cataracts. But recent research has shown that nutritional supplements do not prevent cataracts or keep them from getting worse.
Treatment
For some people with cataracts, a stronger eyeglass prescription and brighter lighting 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.
Cataract surgery has an overall success rate of about 98 percent. According to the National Eye Institute, 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."
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.
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 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." |
