For those of us getting older, bifocals keep things in focus. For nearsighted children, bifocal contact lenses may be able to slow the progression of myopia.
"It turns out that these lenses may be beneficial, not for the reason they were originally designed for adults, but because of the types of optical profiles they create on the back of the eye," said David Berntsen, assistant professor in the UH College of Optometry. "That is one of the current theories for why they may be benefiting children."
Berntsen and research colleagues examined 85 children from 6-11 years old for two years. Some were fitted with single vision spectacle lenses; some with bifocal spectacles. Children wearing the bifocals showed a small slowing in the progression of their nearsightedness.
"The results of the study don't suggest we start fitting these particularly myopic children with progressive addition lenses because the benefit was an extremely small amount," he cautions. " But (the benefit) was present, and, after taking them out of the lenses, that small benefit was still present after another year… For any myopia treatment to be helpful to a child, the benefit has to be there after a year that they stop wearing the lenses, and no study before had done that in a fully randomized clinical trial setting."
He says this is an important step in learning how to better design lenses that decrease how nearsighted a child becomes. Berntsen's research was funded in part by the National Institutes of Health National Eye Institute and was in collaboration with The Ohio State University.
"The fact that the benefit, even though it was small, is still present after a year, is an important thing, a promising thing."
David Berntsen is part of what's happening at the University of Houston. I'm Marisa Ramirez.