Some studies have suggested that hard contact lenses actually improve your eyes, or at least stop them from getting bad quite so fast. Researchers at Ohio State University tested hard and soft contacts in children.

What the researchers wanted to know: How does myopia progress in children using hard and soft contacts?

What they did: Children ages 8 to 11 were eligible to join the study, if their parents gave permission. First there was a run-in period of a few months, during which 147 children wore rigid gas-permeable contacts to see if they could handle them. (Hard contacts can be uncomfortable.) A little under 80 percent of the children adapted to the contacts, and were randomly assigned to wear hard contacts or soft contacts for three years. Obviously, the kids knew whether they were wearing hard or soft contacts, so the treatment wasn't completely secret, but when they went in to have their eyesight checked after one, two, and three years, the person who examined them didn't know which contacts they had (and the children were reminded not to talk about their contacts). Follow-up was unusually good for such a long-term study; every child made it to the three-year exam, although a few missed other visits.

What they found: The children who wore hard contacts had their eyesight decline less than children with soft contacts.

What the study means to you: Wearing hard contacts might help slow the progression of myopia, but the difference between the two kinds of contacts wasn't huge, and the researchers say the improvement may not be permanent; it might wear off if kids stopped wearing hard contacts.

Caveats: Hard contacts aren't for everyone; more than 20 percent of the children in the initial tests found the hard lenses uncomfortable, and many of the children who made it through that phase, then were assigned to wear hard contacts for the study, stopped wearing them.

Find out more: Information on contacts from the American Optometric Association

Read the article: Walline, J.J., et al. "A Randomized Trial of the Effects of Rigid Contact Lenses on Myopia Progression." Archives of Ophthalmology. December 2004, Vol. 122, pp. 1760-1766.

Abstract online: http://archopht.ama-assn.org