Lazy Eye Identified by Age 2 Using New Device
To effectively reverse lazy eye, it is best to identify and treat it before a child is 4 or 5 years old. Now a new device allows doctors to detect this potentially serious eye problem in children as young as age 2 years.
New scanning device could save vision
Lazy eye, also known as amblyopia, is the loss or lack of development of central vision in one eye that is not related to other eye conditions and is not correctable with lenses. The condition affects 3 to 5 percent of young children and if untreated, it can result in permanent vision loss in one eye.
Amblyopia typically starts when one eye is better able to focus than the other eye. This inability to focus properly may be due to nearsightedness, astigmatism (irregular curvature of the cornea), or strabismus (the eye turns inward or outward). Over time, the brain ignores the poorer image, and vision in the affected eye deteriorates.
A new handheld scanning device, called the Pediatric Vision Scanner, was recently tested by ophthalmologists at Children’s Hospital Boston in 202 children ages 2 to 18 years. A total of 154 pediatric patients at Children’s ophthalmology clinic and 48 children with normal vision were screened.
The new device allows clinicians to measure alignment (binocularity) of the eyes using low-power laser scans that take five readings in only about 2.5 seconds. This approach is ideal because young children cannot reliably communicate what they can or cannot see during a vision test, and this device eliminates the need for any input from the child, plus it is quick and painless.
Among children ages 2 to 6 years, binocularity scores averaged 9 percent among those with lazy eye and 8 percent for those with strabismus. (A binocularity score lower than 60 percent indicated a need for further examination.) Binocularity scores among controls was 89 percent.
The scanning device was also able to detect amblyopia in children who did not have measurable strabismus. According to senior author David Hunter, MD, chief of ophthalmology at Children’s, “the fact that the device could detect any form of amblyopia was completely unexpected and a key advance for making more accurate referrals.”
Hunter noted that some states mandate eye exams be performed before children enter school, but this is too late to most effectively treat amblyopia. He hopes the new scanning device will be utilized by pediatricians to screen toddlers and preschoolers, because it “has the potential to give pediatricians the tool they need to quickly and easily identify those kids most in need of a specialist eye exam as soon as they develop a problem.”
Early detection of lazy eye allows physicians to treat it using eyedrops or a patch over the stronger eye, which forces the child to use the weaker eye. However, “once a child reaches school age, treatment is less likely to restore useful vision,” said Hunter.
The new device to identify lazy eye in very young children is the result of two decades of research funded by various agencies. Several independent centers are currently testing a lighter, more user-friendly prototype. Eventually, Hunter hopes health insurers and government entities will accept the test, as it could potentially save sight “in hundreds of thousands of children.”