MONDAY, Dec. 27, 2010 (HealthDay News) -- When medical experts talk about prevalence, they're usually referring to how common a particular disease might be. But in the case of cataracts, they might just as well be talking about how common it is to uncover misinformation and misunderstanding about the condition.
Cataracts are a leading cause of blindness among seniors in the United States, with more than half of all U.S. residents developing the cloudy vision of cataracts by the time they reach 80 years old, according to Prevent Blindness America, a nonprofit group that focuses on eye health.
But eye experts say that people seem to believe things about cataracts that aren't quite right, including when and how they should be treated. Misinformation often seems to develop innocently enough, with well-meaning folks spreading things they've learned by word-of-mouth.
"Sometimes friends give confusing and conflicting information because not every patient is the same or because they've heard something from someone else," said Dr. Cynthia Bradford, an ophthalmology professor at the University of Oklahoma's Dean A. McGee Eye Institute.
Nonetheless, the misinformation sometimes leads people to delay treatment long past when it could help them or to expect too much from treatment for this widespread vision problem.
Cataracts occur when the lens of an eye grows cloudy, according to the U.S. National Eye Institute. Vision might grow progressively cloudy until the person has difficulty seeing, or the person's vision might take on a brownish tint that makes it harder to distinguish colors.
And that leads to one of the first major myths -- that cataracts are something that grow on top of the eye.
"A lot of people think of it as a growth, but it's almost like honey that's become granulated," Bradford said. The lens itself is the problem, which is why cataract surgery requires that the lens be removed and replaced.
More than 20 million Americans age 40 and older have cataracts, and the condition is most often associated with aging. "The lens of your eye changes as you get older, just like your skin begins to look different," Bradford said.
But cataracts don't develop only in senior citizens. "The majority of cataracts are due to aging, but there are cataracts that are caused by other risk factors," said Dr. Stephen Pflugfelder, a cataract expert on the faculty at Baylor College of Medicine in Houston. They include:
- Trauma to the eye
- Long-term steroid use
- Long-term exposure to the ultraviolet rays contained in sunlight
- Severe long-term nearsightedness
Once someone has developed cataracts, misunderstanding seems to abound regarding when they should be treated.
For starters, many seem to believe that someone with a cataract should wait for the lens to go completely white before receiving surgery. That's because they're remembering the old days, when cataract surgery was much chancier, Bradford and Pflugfelder said.
"Some older people remember the surgery when it was really invasive," Pflugfelder said. "Patients had to lie down with sandbags on either side of their heads so they couldn't move. Not so anymore."
On the other hand, some people think they must seek out treatment the minute they've been diagnosed with a cataract. But that's not right, either, the experts say.
"The presence of a cataract is not an indication to take it out," Bradford said. Eye physicians often recommend that people wait to pursue treatment until a cataract has begun to interfere with their quality of life or their ability to work.
Cataract treatment is another area fraught with misinformation. Some people think that there are eye drops that cure or treat cataracts by dissolving them or slowing their progress, according to Prevent Blindness America. But the organization says that's just not true.
Surgery is the only proven treatment for cataracts, and its safety record is much better than many people believe. More than 95 percent of cataract surgeries are successful and performed free of complications, according to Prevent Blindness America.
"The surgical treatments are outstanding, and they keep getting better as it becomes less and less invasive," Pflugfelder said. Surgeons today can remove clouded lenses through microscopic incisions as small as 2.2 millimeters, using tiny implements to chop up the lens with ultrasound waves and suction it from the eye. Cataract surgery often is done in about half an hour, and people go home able to see out of the eye the same day.
Replacement lenses also are getting better, but Pflugfelder and Bradford cautioned that they still are not perfect. Multifocal lenses can allow people to see up close as well as at a distance, but many people will still need glasses to help them read after surgery, they said.
"The outcome of current cataract surgery is very good, but we can't promise everyone they won't need glasses," Bradford said.
The American Academy of Ophthalmology has more about cataracts.
For more on cataract surgery, read about one woman's story.