Vision Screening in Toddlers Flags Amblyopia Risks

Linda Roach

February 12, 2013

Automated photoscreening can detect amblyogenic risks in young toddlers as reliably it does in older preschoolers, supporting a recommendation that pediatricians initiate such screening in their patients at 1 year of age, Iowa researchers have concluded.

"Our results support screening at an earlier age. You can screen children between ages 1 and 3, and the results will be as reliable as they are for children between 3 and 5 years," Susannah Q. Longmuir, MD, assistant professor of ophthalmology at the Department of Ophthalmology and Visual Sciences, University of Iowa Hospitals and Clinics, Iowa City, said to Medscape Medical News. The study by Dr. Longmuir and colleagues was published online February 11 in Pediatrics.

Their conclusion clashes with that of the US Preventive Services Task Force, which in 2011 declined to recommend vision screening for children younger than 3 years. The task force wrote that "the current evidence is insufficient to assess the balance of benefits and harms of vision screening for children <3 years of age."

Convinced that early detection and treatment are essential, leaders in pediatrics and ophthalmology have been working to reverse that decision since then.

"One of the reasons we wanted to do this study was to support screening at an earlier age than is currently recommended by the task force. Because as pediatric ophthalmologists we want to try to find these kids early," Dr. Longmuir said.

The researchers analyzed 11 years of data from KidSight, a statewide vision screening program for preschoolers that referred children with amblyogenic risk for further evaluation. Between 2000 and 2011, KidSight screened 210,695 children (mean age, 3.4 years) with a single type of automated system. Among those screened were 42,149 children aged 6 months to 3 years.

Photoscreening instruments work by capturing images of the red reflex from both eyes simultaneously and then evaluating them to estimate refractive error and to identify other amblyogenic risk factors, such as ocular alignment, pediatric cataract, and ptosis.

Positive Predictive Value 89%

In the Iowa children, 5.9% of the photoscreens were unreadable, and the overall positive predictive value for the detection of any amblyogenic risk factor was 88.8%. In children between 1 and 3 years of age, the positive predictive value was 87.4% (95% confidence interval [CI], 84.5% - 89.9%), and for 3- to 5-year-olds it was 89.4% (95% CI, 88.3% - 90.4%). The difference was not statistically significant (P = .15).

In an interview with Medscape Medical News, Sean P. Donahue, MD, who was part of an American Association for Pediatric Ophthalmology and Strabismus panel that recently reviewed the literature on photoscreening, praised the Iowa study's rigor.

"This is the most robust data that have been published on this topic in some time," said Dr. Donahue, who is Coleman Professor and chief of pediatric ophthalmology at Vanderbilt Medical Center at Vanderbilt University in Nashville, Tennessee.

This opinion was echoed by the American Association for Pediatric Ophthalmology and Strabismus president, K. David Epley, MD, of Kirkland, Washington, in a separate interview. "This is large study with a huge number of children and a lot of valuable data that suggests that screening can detect these kids at a much younger age than we thought possible before, when their brains are more receptive and they're easier to treat."

The data are strong enough to support having a photoscreening system in every pediatrician's office, Dr. Epley said. Recently, vision screening became a reimbursable service, with its own Current Procedural Terminology billing code, he noted.

"Now is the time to start doing this in your office, because vision screening takes less time than ever before, you can get reimbursed, and you'll be able to detect the 2% to 4% of children who have amblyopia and prevent them from being blind in one eye. That's a huge deal."

The study received no external funding. The authors have disclosed no relevant financial relationships. Dr. Donahue has been a consultant for Rebiscan, Diopsys, PediaVision, and Welch-Allyn.

Pediatrics. Published online February 11, 2013. Abstract