“Not only can cataract surgery give people a better life while they’re living it, they can also live more of it,” Dr. Coleman said in an interview. The women in the study who underwent cataract surgery lived longer even though, over all, they were sicker to begin with — as a group, they had more heart attacks, chronic pulmonary disease, peptic ulcers and glaucoma than those who did not have surgery.

Previous studies had shown a lower mortality risk in men as well as women following cataract surgery, Dr. Coleman said. The new study, while confirming the earlier findings of fewer deaths in women, was also large enough to show just how the operation can extend life. Those who had cataract surgery subsequently had reduced risks of death from cardiovascular, pulmonary, neurological and infectious diseases, as well as cancer and accidents.

In explaining this result, Dr. Coleman said that when people can see better, “they can also move more and get more exercise. They can see their pills better and may be more likely to take them and take the right ones. The surgery also improves visual contrast, which decreases the risk of accidental deaths from falls or driving. It’s important to get the best vision a person can have.”

Although there are some risks associated with removing cataracts, “it’s probably the most successful surgery we have — it has a 98 percent success rate,” Dr. Coleman said. Potential complications, albeit rare, include infection, inflammation, retinal detachment and double or shadow vision.

There have also been extraordinary advances in cataract surgery since the 1980s. Earlier, the surgery was done under general anesthesia and patients spent nights in the hospital and weeks in bed recovering. Today, the procedure is done with a local anesthetic and the incisions are much smaller, often requiring no stitches. One eye is operated upon at a time, with the second one typically done about two weeks later, and recuperation is fast.

As Ms. Quinn put it, the surgery “was quick and easy — maybe five minutes — and it was like a miracle. I couldn’t believe how well I could see right after the first eye was done.”

Specialists now also recognize the wisdom of not waiting until a cataract is “ripe” and vision seriously diminished before urging patients to consider surgery. Dr. Coleman said, “The longer you wait, the more difficult the operation. It’s easier to remove cataracts before they become too dense.”