April 12, 2005 - For kids with lazy eye, a window of opportunity just opened wider.
Doctors always thought that lazy eye, also called amblyopia, had to be treated in the preschool years. Older kids, the thinking went, missed their chance for treatments that force children to use and strengthen their lazy eyes.
Phooey to all this, says an important new study. It shows that 53% of 7- to 12-year-olds with lazy eye respond to treatment regardless of whether they'd been treated before. Moreover, 47% of previously untreated 13- to 17-year-olds also responded to treatment.
Interestingly, about one in four kids saw a lot better merely by getting new prescription eyeglasses.
"Responded to treatment" means the children saw two extra lines on an eye chart. That's significant, but they did not achieve perfect vision. And it's not yet clear whether this improvement will last or whether extra treatment will maintain or improve the kids' vision.
"The opportunity to treat amblyopia does not end with the pre-school years," study co-leader Mitchell M. Scheiman, OD, of the Pennsylvania College of Optometry, says in a news release.
"Previously, patients were told there was nothing that could be done to help them. Now there is something we can do, and it has immediate results," study co-leader Richard W. Hertle, MD, of Children's Hospital of Pittsburgh, says in a news release.
The researchers report their findings in the April issue of Archives of Ophthalmology.
Scheiman, Hertle, and colleagues studied 507 kids with lazy eye, a condition in which the brain gets unequal input from each eye. Affecting up to 3% of U.S. kids, lazy eye may be caused by eyes that cross inward or turn outward, by vision differences between the two eyes, or even by eye injury.
Half the kids simply got new prescription eyeglasses. The other half underwent treatment to strengthen their lazy eyes.
The younger group - those aged 7 to 12 - wore eye patches over their "good" eye for two to six hours a day. Most also got eye drops that blurred the vision in their "good" eye. Then the kids had to perform "near visual activities" -- playing on a GameBoy, doing homework, reading, working on a computer, or using special workbooks with mazes and other activities. All of this helps force the children to use their lazy eye and strengthens the muscles that control the lazy eye.
The older group -- aged 13 to 17 -- wore eye patches for two to six hours a day and performed near visual activities. They did not get eye drops, as the researchers worried that this would cause too much interference with their daily activities.
"Doctors can now feel confident that traditional treatments for amblyopia will work for many older children," Paul A. Sieving, MD, PhD, director of the National Eye Institute, says in a news release. "This is important because ... many of these children do not receive treatment while they are young."
Early Lazy Eye Treatment Still Important
It's still vitally important to treat children with lazy eye as soon as possible, argues David G. Hunter, MD, of Children's Hospital Boston and Harvard Medical School.
In an editorial accompanying the study, Hunter notes that most of the older kids in the study did not benefit from treatment.
"The take-home lesson is that considering how difficult it is to treat older children for amblyopia, it is vitally important to identify and treat amblyopia early in life, well before the age of 7 years," Hunter writes.