In this randomized clinical trial conducted at 30 sites across the United States, Canada and Mexico, 175 children with visual acuity of 20/100 to 20/400 in the amblyopic eye were prescribed patching for six-hour or full-time regimens. At least three to four percent of children in the United States suffer from amblyopia, a condition that decreases vision, most often due to crossing of the eyes or having one eye with uncorrected refractive error (i.e. farsightedness, astigmatism or high nearsightedness).
After four months, the improvement in visual acuity in the six-hour group was nearly identical to the improvement in the full-time group. Jonathan M. Holmes, MD, a pediatric ophthalmologist at the Mayo Clinic and co-chair of the Pediatric Eye Disease Investigator Group, said patching for fewer hours eases implementation of the therapy and compliance monitoring for parents. Dr. Holmes, who chaired the study, further explained, "The caveat should be that if the child doesn't respond to six hours per day, then increased patching intensity should be considered. But for severe amblyopia, it is reasonable to start with six hours a day of patching, rather than full-time patching."
"This is the latest in a series of important research results that will help preserve the vision of children with amblyopia," said Paul A. Sieving, M.D., Ph.D., director of the National Eye Institute (NEI), National Institutes of Health, the Federal government agency that funded the study.
According to Academy spokesperson Stuart Dankner, MD, the study shows that children with more severe amblyopia may respond just as well to a shorter six-hour interval of patching therapy of the good eye as those children who previously required full-time patching." Dr. Dankner, MD, a pediatric ophthalmologist in Baltimore and an assistant professor of ophthalmology at Johns Hopkins University and the University of Maryland, School of Medicine, said, "Less than full-time patching may actually lessen the risk of patching-induced amblyopia in the good eye. Many of the children with more severe degrees of amblyopia may benefit from this change in patching therapy, assuming the disease is detected at an early enough age."
"Most children achieved an outcome in the 20/32 to 20/63 range, but it is important to note that this study was not designed to determine the maximal improvement that could be achieved," Dr. Holmes said. "Most children stayed on treatment for many months after the conclusion of the study to further improve their vision."
The American Academy of Ophthalmology is the world's largest association of eye physicians and surgeons--Eye M.D.s--with more than 27,000 members worldwide. For more information about eye health care, visit the Academy's partner Web site, the Medem Network, at www.medem.com/eyemd. To find an Eye M.D. in your area, visit the Academy's Web site at www.aao.org.
Journal
Ophthalmology