Caroline Helwick

October 27, 2013

ORLANDO, Florida — Portable vision screening devices can simply and accurately identify vision problems in young children, according to a study that evaluated the sensitivity and specificity of 4 such devices.

"New photoscreeners can hit their target, even in high-risk young and special-needs children," said Robert Arnold, MD, of Alaska Blind Child Discovery in Anchorage.

"Approximately 15% of children aged 3 to 5 have vision problems that can threaten normal visual development," he pointed out here at the American Academy of Pediatrics (AAP) 2013 National Conference and Exhibition.

"With the publication of new AAP photoscreening guidelines and CPT reimbursement code (99174), pediatric practices are pondering which of the new photoscreening devices would work best to reduce amblyopia in their practice environment," Dr. Arnold said.

His team tested the effectiveness of 4 state-of-the-art portable vision screening devices in 108 consecutive pediatric patients in an Alaskan pediatric eye practice. Children were aged 6 months to 10 years, and those with developmental delay were not excluded from the study.

Each child received a comprehensive examination, followed by screening with each of the vision screening devices, including the iScreen, SPOT, Plusoptix, and iCheckKids device, which attaches to a smartphone and will soon be renamed GoCheckKids.

"All 4 photoscreeners were effective," Dr. Arnold reported. "Each device has advantages with adjustable interpretation by Plusoptix and Spot, rapid aim and image with online interpretation with iScreen, and handheld iPod Touch portability with iCheckKids," he explained. "The iScreen is particularly useful in children with difficult fixation and attention. The iCheckKids yielded useful photoscreen images."

The sensitivity and specificity of the devices were comparable, and outcomes were similar for preschool-age and developmentally delayed children.

Table. Photoscreener Sensitivity and Specificity

Device Sensitivity (%) Specificity (%)
iScreen 75 88
Spot 80 85
Plusoptix 83 88
iCheckKids 81 91


All the devices are expected to improve with enhanced interpretation paradigms, Dr. Arnold said. Further efforts to validate the devices will occur in pediatric offices and community screening settings.

"Photoscreening is exquisitely capable of detecting the most common and the most treatable amblyopia risk factors, such as insufficiently accommodated hyperopia or farsightedness," Dr. Arnold noted. "Recent technological developments in devices and interpretation, combined with reimbursement and guidelines, promise to improve early screening for amblyopia."

In a separate presentation, Joannah Vaughan and colleagues from Casey Eye Institute at Oregon Health and Science University in Portland evaluated the iCheckKids photoscreening app used with an iPhone 5 and found "adequate" diagnostic accuracy, but suboptimal quality control.

The app takes standardized flash photographs at a target working distance of 28 inches in 2 modes, portrait and landscape, and measures refraction from the photographs.

Smartphone App

Vaughan and her team examined 23 individuals, 19 of whom had usable data. Of these, 7 were referred by clinical examination ― 5 for astigmatism, 1 for myopia, and 1 for exotropia. The iCheckKids app correctly referred 6 of 7 of these patients, for 86% sensitivity; 1 patient with astigmatism was missed, the researchers report.

Of the 6 patients referred by both clinical and iCheckKids criteria, the diagnosis agreed in 5, but in 1 patient, the clinical examination identified astigmatism whereas iCheckKids identified exotropia. There were no false positive referrals, giving 100% specificity for the photoscreener.

The researchers suggested that diagnostic accuracy was acceptable, but they said they felt that better quality control is needed through training and automation to provide real-time feedback to the operators, particularly with regard to patient fixation and pupil size.

Joel Zaba, MA, OD, from Virginia Beach, Virginia, author of the report, Children's Vision Care in the 21st Century and Its Impact on Education, Literacy, Social Issues, and the Workplace: A Call to Action, told Medscape Medical News that vision problems in childhood have far-reaching consequences throughout life ( J Behav Optom 2011;2:39-41).

"Vision problems are one of the most prevalent handicapping conditions in childhood," he said, "and the failure to detect and treat children's vision disorders affects the rates of adult criminality, literacy, and labor productivity."

He emphasized the need to regularly check schoolchildren for vision problems using multiple tests to identify a wider spectrum of problems, especially those affecting near-vision.

Commenting on the current study, Dr. Zaba said, "It is very important to find the most effective devices to screen for amblyopia. However, one must consider the other significant visual problems, which can be found at the near-point viewing distance in children, which is approximately 13 to 18 inches from their eyes."

He pointed out, "Schoolchildren are using their near-point visual skills for computers, tablets, cell phones, reading, and writing at early stages in the classroom. They are doing more close-up visual work than any other schoolchildren in the history of the educational environment. The same relates to adults as well. Therefore, it is imperative that we consider additional near-point screening evaluations for binocular, accommodative, and eye motility abilities."

Dr. Arnold reports that he is a board member of Glacier Medical Software, which Markets NICU software ROP-Check. Alaska Blind Child Discovery has received discount vision technology from several vendors. Dr. Zaba reports no relevant financial relationships.

American Academy of Pediatrics (AAP) 2013 National Conference and Exhibition. Presented October 26, 2013.


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