Screening device accurately detects amblyopia (lazy eye): Early detection is key to treating condition that can affect children’s success in school and lifelong visual acuity

According to a study published by the Journal of the American Association for Pediatric Ophthalmology & Strabismus, a handheld screening device that accurately detects subtle misalignment of the eye can identify children with amblyopia (lazy eyes).
The National Eye Institute (NEI), director of research and development, said that the findings suggested that primary care physicians and pediatricians could use the device to catch amblyopia early when it is easier to treat. The National Institutes of Health includes the NEI.

Amblyopia, which is a condition that impairs vision in one eye, is the leading cause for preventable monocular (single-eye) vision loss. It affects three out of every 100 children living in the United States.

Our brains develop in childhood and learn to combine images from both eyes to create vision. When the brain is unable to process visual information from both eyes properly (strabismus), or if one eye has decreased acuity, amblyopia can develop. Contact lenses or glasses cannot correct vision in the weaker eye after a child has reached visual maturity.

Amblyopia can lead to poor school performance, impairments in depth perception, and impaired fine motor skills like handwriting and other handeye-coordinated activities.

To treat amblyopia, a patch is placed over the eye that has the best vision to help the weaker one. As children age, patching becomes less effective. Early detection is crucial. This depends on the timely diagnosis of the child's physician. Most pediatricians are only equipped for basic vision screening tests. These tests are not helpful in detecting amblyopia in young children.


The screening device measures the ability of both eyes to fixate together. The device is held 14 inches away from the child's eyes and the child fixes his smiley face on the screen. A polarized laser is used to scan the retinas using a probe. This area is crucial for central vision. A subtle misalignment in the foveas, called small-angle straboism, can cause brain problems when trying to combine images from both eyes. The device calculates a score called the binocularity score, which indicates whether the child should be referred to an eye doctor for further examination.

The study involved 300 children between 2 and 6 years old with no eye problems. They were recruited at two Kaiser Permanente Southern California pediatric clinics.

The device was used to screen each child by two non-ophthalmic researchers who were trained in its use. They were then compared with the results of an eye exam performed by a pediatric surgeon who was not aware of the device's results. The device detected six cases (100% sensitivity), of amblyopia or strabismus, which had been confirmed by an eye exam. Additional 45 children were also identified by the device as potentially having amblyopia or strabismus. These were later confirmed by an eye exam to be normal (85% specificity).

Shaival S. Shah M.D. is a Kaiser Permanente pediatric ophthalmologist based in Tustin Ranch. "In the hands a trained user it takes 28 seconds for the child to sit down, perform the test and record the results. This is important considering that its adoption in busy pediatric settings will be possible," Shaival S. Shah said. The test takes 2.5 seconds to complete.

The study had a major limitation in that the device could not be compared to other photo-screening devices. These devices detect differences between the light reflexes of each eye and produce images that can help identify risk factors for amblyopia. However, they do not detect amblyopia. This can lead to both under and over detection.

The pediatric vision scanner, on the other hand, detects amblyopia and not the risk factors. This may result in fewer referrals to pediatric eye doctors.

A prototype of blinq was used in the pediatric vision screening. The U.S. Food and Drug Administration approved the device in 2016.

NCT02536963 is the clinical trial identifier. Rebiscan, Inc., a Boston-based company that sells blinq, was awarded NEI grant R44EY025926. The SBIR program is a funding mechanism that allows independently-owned companies with 500 employees or less to bring biomedical technology to the market.

Co-founder of Rebion, David Hunter, M.D., Ph.D., ophthalmologist-in-chief at Boston Children's Hospital, co-invented blinq. with support from NEI grant R01EY012883.