Children's Hospital Boston chief of ophthalmology Dr. David Hunter created technology for detecting amblyopia, known commonly as “lazy eye,” ten years ago, but he wants to make screening for all preschool-age children routine.
Children with “lazy eye,” or amblyopia, have structurally intact eyes that may appear normal. But one eye isn’t used, generally because of a subtle misalignment. Unless someone notices this early enough, the “lazy” eye can slowly go blind, simply because the brain hasn’t received proper stimulation from it. It’s learned to ignore input from that eye.
“While amblyopia is easy to treat if you get to the kids early, it’s hard for us as ophthalmologists to get to the kids early because often the condition isn’t detected in the pediatric office,” says David Hunter, chief of ophthalmology at Children’s Hospital Boston.
Treatment consists of patching the sound eye, forcing the child to use the weaker eye. Ideally, this should be started before age 5, when the brain is still able to relearn; once a child reaches 8 to 10 years it’s often too late to restore his vision.
Over a decade ago, while at Johns Hopkins, Hunter came up with the idea of a device that would measure the eyes’ alignment and focusing ability by scanning the retinas as the child looks at a target (a small smiley face) and analyzing the light coming back from each eye.
He created a prototype of what’s now called the Pediatric Vision Scanner and tested it in children coming to his ophthalmology clinic at Children’s. It was able to detect well over 95 percent of children who had an eye problem. “No one’s ever seen that kind of accuracy in a screening device,” he says.