Cataracts are the leading cause of reversible vision loss as we age. According to Prevent Blindness America, more than half of all Americans have them or have had surgery for them by the time they reach 80. The condition causes vision to become progressively clouded; a process that happens so gradually you may not be aware of any impairment until a cataract is fairly advanced.
However, cataracts don’t just affect vision—they also raise your risk of falls. That risk may be reduced substantially if cataracts are removed, according to a new study. Previous research also suggests that surgical correction of visual impairment due to cataracts can boost longevity.
Cataracts and falls
A study presented at the 2014 annual meeting of the Association for Research in Vision and Ophthalmology, in May, found that cataract surgery dramatically decreases the number of falls people suffer due to poor vision. In the study of almost 400 adults age 50 and older, the number of falls patients suffered before and after cataract surgery was monitored. Researchers found a 78 percent decrease in the risk of falls the year after patients had cataract surgery on one eye.
Other research underlines the safety benefits of cataract removal. One study indicated that cataract surgery can reduce the risk of falls and hip fractures in older adults, while a 2013 analysis found that surgical correction of visual impairment due to cataracts was associated with significantly better long-term survival of seniors.
What are cataracts?
Kevin M. Miller, MD, Kolokotrones professor of clinical ophthalmology at UCLA’s Jules Stein Eye Institute, says that a cataract is essentially a clouding of the lens that occurs as a result of oxidative and other chemical changes to the eye.
In healthy eyes, light passes through the cornea and lens to the retina (an area of light-sensitive tissue at the back of the eye), where it is changed into signals that are transmitted to the brain via the optic nerve. “In order for the retina to receive a sharp image the lens needs to be clear,” says Dr. Miller. “When a cataract develops the lens becomes cloudy and eventually opaque. This in turn blurs the image we see—the effect is almost like looking through a fogged-up window.”
Cataracts are most likely to develop in people with a family history of the condition, previous eye injury and/or previous eye surgery. Smoking, diabetes, prolonged use of corticosteroids, excessive exposure to sunlight, and smoking also raise the risk. They may also develop due to normal age-related changes in the eye. “The lens itself is formed from cells that have low water content and are packed together in such a way that the lens is transparent,” says Dr. Miller. “As we age, it’s possible for lens proteins to aggregate, or cluster, causing a small clouded area that gradually spreads.”
Opting for removal
Dr. Miller says that initially you may not notice that your vision is rendered less sharp by your cataracts. “But as the cataract increases in density, the visual blur increases and you become more sensitive to glare,” he adds.
Seeing will gradually become more difficult as the process continues, and once a cataract is affecting your ability to carry out everyday tasks, you should consider surgery to remove it. “Anyone who is having significant difficulty with visual tasks like reading, driving, and watching television due to cataracts is eligible for cataract surgery,” Dr. Miller confirms. “In the hands of a competent, well-trained surgeon, the procedure is safe and effective.”
Cataract surgery typically takes about 30 minutes. In standard cataract removal, a tiny incision is made in the cornea (the transparent front of the eye), and the lens capsule (a clear membrane that surrounds the lens). An ultrasound probe is then inserted—the waves it emits break up the lens into small pieces, which are then removed using suction. A newer method utilizes a state-of-the-art laser (Femtosecond) to perform bladeless laser cataract surgery, and has the potential to provide even more precise eye surgery. Research suggests that the Femtosecond laser reduces the average time and energy required to break up and remove the eye’s natural lens by approximately 50 percent, and that it also may result in less post-operative swelling and inflammation.
After the old lens is removed, a clear plastic artificial lens is inserted through the incision. “You can choose from a monofocal lens, which allows for fixed distance vision, or a multifocal lens, which enables distance and near vision,” Dr. Miller says. “You’ll see an improvement in your vision immediately, but you may need to wear an eyeshield or glasses while your eye recovers.”
Dr. Miller notes that Femtosecond isn’t the only new advance in cataract removal. Toric replacement lenses can help to alleviate astigmatism, a condition in which vision is slightly distorted or blurred due to the eye’s cornea or lens having an oval instead of round shape. “There are also new devices for verifying that the replacement lens power calculation is accurate,” Dr. Miller adds. “I’m also participating in the clinical trial of a lens implant whose powers can be adjusted weeks after implantation to fine-tune the postoperative vision correction.”
Powered by WPeMatico