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The risk of a person's retina detaching after having a cataract removed is dropping, says a new study.

Australian researchers found that the number of people who needed their retina reattached after their cataract was removed fell from about one in 100 between 1989 and 1993 to one in 400 between 1999 and 2001.

"It makes great sense to me," said Dr. Jack Cioffi, chair of Columbia University Medical Center's department of ophthalmology in New York.

Cioffi, who was not involved with the new study, said he thinks the reduction is most likely thanks to improvements in technology and the ability of doctors to adapt to new procedures.

One such improvement, phacoemulsification extraction, was first adopted in the mid-1980s and is now the preferred procedure for cataract surgery. Cioffi said it was a harder method to learn, but allowed doctors to be less invasive compared to the old procedure.

During cataract removal, a doctor numbs a patient's eye with drops and cuts into the top of the eye. The doctor then replaces the cloudy lens with a clear artificial version.

Cataract removal is one of the five most common outpatient procedures in the United States, according to the Centers for Disease Control and Prevention (CDC). About three million cataract removals are performed every year in the U.S. The procedure costs about $3,000 and is more common in the elderly.

The researchers, led by Dr. Anthony Clark of Curtin University in Perth, said past studies showed retinal detachment is one of the most common sight-threatening complications after cataract surgery.

Cioffi said there is a possibility that doctors can reattach a person's retina - the part of the eye responsible for sending images to the brain - but there is a chance the patient could lose sight in that eye.

How the risks have changed

To see whether the risk of retinal detachment has gone down since phacoemulsification was adopted, the researchers used data to see how many people in Western Australia were hospitalized for retina reattachment surgery after having a cataract removed between January 1989 and December 2001.

They found that of more than 46,000 people, 237 needed retina reattachment surgery after having more than 65,000 cataracts removed.

When the researchers then looked at five-year spans between 1989 and 2001, they found retinal detachments happened more often at the beginning of the study.

Specifically, the incidence of retinal detachment following cataract removal between 1989 and 2003 was about 1 percent. That fell to 0.43 percent between 1994 and 1998, and then again to 0.25 percent between 1999 and 2001.

"What it shows is that our patients are safer now with cataract surgery than they were in the past," said Dr. Jay Erie, chair of the department of ophthalmology at the Mayo Clinic in Rochester, Minnesota.

Erie, who was not involved with the research, told Reuters Health the results are encouraging since the age of the U.S. population - as a whole - will increase in the coming years.

But Dr. Sam Garg, a professor of ophthalmology at the University of California, Irvine, said - like any procedure - cataract removal does have risks, and those should be discussed with a doctor.

For example, the capsule containing the lens could rupture, which requires an additional procedure that the researchers found is linked to an increased risk of retinal detachment.

That complication, however, is not common and the extra procedure was performed on less than 1 percent of the patients in the new study.

They also found that men and younger people were more likely to need their retina reattached after cataract surgery. They say these links have been seen in previous studies and are most likely due to biological differences between the young and old, and men and women.

Overall, Garg, who was not involved with the new research, told Reuters Health that cataract surgery is a very common and very safe procedure. And he said that not all cataracts require surgery.

"Cataracts are one of those things that everyone gets... Does it always cause problems? No. Do you always have to treat it? No," said Garg.

According to the CDC, more than 17 percent of Americans over the age of 40 are living with cataracts, and more than 5 percent have had a cataract removed.