Apr 23 2005
For decades, vision specialists believed that a condition called amblyopia, or "lazy eye," must be treated before a child turns 7 to be successful. But a new study, involving Vanderbilt Children's Hospital researchers, finds it's not too late for older children.
Amblyopia is a leading cause of vision impairment in children affecting about 2.2 million in the United States.
The National Eye Institute's (NEI) nationwide study, led locally by Sean Donahue, M.D., Chief of Pediatric Ophthalmology for the Monroe Carell Jr. Children's Hospital at Vanderbilt, found that patching the strong eye to allow the weaker eye to `catch up` can work well into the teenage years.
In the study half of the children were given the standard treatment of prescription glasses, while the other half used a patch over the strong eye to `work` the weaker eye two to six hours a day. A total of 507 children ages 7 to 17 were enrolled nationwide. The Tennessee Lion's Eye Center was one of two participating vision centers in the state of Tennessee. The results, which appear in the April issue of Archives of Ophthalmology found more than half of the older children who got the patching treatment improved their vision significantly, while 20 percent of the children with glasses improved their vision.
`What was surprising was that the patching helped many children up to age 17. That suggests the brain is more malleable at a later age than we thought,` Donahue said. `This is big for parents. It demonstrates conclusively that it is a good idea to bring older children with amblyopia in for evaluation of treatment.`
`When I took my son to a doctor in our hometown, he just prescribed glasses and said that after the age of 6 there wasn't anything else we could do,` said Pulaski, Tennessee resident April Rose, mother of 11-year-old Brandon whose lazy eye was not apparent until he began school and noticed he had difficulty reading. But after just two months of using eye drops that blurred the vision of his strong eye, Brandon's eyesight has gone from 20/70, to 20/25.
"Unfortunately, Brandon is typical for a patient with amblyopia,` said Donahue. `Probably 30 or 40 percent of amblyopia patients don't have a visible misalignment, but they fail vision screening in first grade, when we traditionally thought it was too late to patch."