Early instrument-based vision screenings endorsed for preschool children

Amblyopia is the most common cause of visual impairment among young children, and its onset is both detectable and preventable. Although avoidable, the functional defect affects approximately one to two out of every 100 children, according to the National Eye Institute.

Last year, the American Academy of Pediatrics, the American Academy of Ophthalmology, the American Association for Pediatric Ophthalmology and Strabismus, and the American Association of Certified Orthoptists published updated instrument-based pediatric vision screening guidelines, highlighting the importance of amblyopia detection.

According to the guidelines, “photoscreening and handheld autorefraction may be electively performed in children 6 months to 3 years of age, allowing earlier detection of conditions that may lead to amblyopia.”

To David G. Hunter, MD, PhD, ophthalmologist in chief at Boston Children’s Hospital, the updated vision screening guidelines are exciting and helpful, and they are being welcomed with open arms.

“At long last, there’s recognition that testing vision in young kids is important,” Hunter said. “Testing vision can save a child’s sight by testing and referring early. There’s now an alternative to sending every child for an eye exam, and so it’s going to raise awareness and set the path toward eliminating amblyopia as a cause of vision loss, or at least reducing it.”

Updates to the guidelines

Previous statements released by the American Academy of Pediatrics called instrument-based screenings experimental. The new statement, published in Pediatrics, calls instrument-based screenings the “preferred methodology” in the detection of risk factors for amblyopia and maintains that the automated screenings “are recommended as an alternative to visual acuity screening with vision charts.”

“The goal of vision screening is to detect subnormal vision or risk factors that threaten visual development, preferably at a time when treatment can be initiated to yield the highest benefit,” according to the policy statement.

According Sean P. Donahue, MD, PhD, chief of the pediatric ophthalmology service at Monroe Carell Jr. Children’s Hospital at Vanderbilt, the most exciting change is the ability to screen children who previously could not be adequately screened.

“The new guidelines help because they allow children to be screened at a younger age when treatment is not only easier, but much more likely to be successful,” he said.

It became necessary to update past guidelines because various study data supported advanced technology and screening instruments now available to pediatricians and pediatric ophthalmologists, according to an evidence-based update published in the Journal of AAPOS.

Hunter also acknowledged the numerous data in support of the importance of vision screening guidelines for children.

“It’s especially exciting to see that some of the papers based on this policy statement are now recognizing that this really is meaningful and is going to be helpful to the quality of life of our children,” he said.

Detection of amblyopia

Amblyopia is characterized by visual acuity loss without obvious structural anomalies, such as optic nerve hypoplasia, according to Robert W. Arnold, MD, a member of the AAPOS Vision Screening Committee.

It is associated with early and persistent disruptions in clear, aligned vision, which can be attributed to risk factors including constant strabismus, high anisometropia, high hyperopia and high astigmatism, he said.

“A primary goal of vision screening in young children is the detection of amblyopia or the risk factors for development of amblyopia, a neural deficit in vision that is estimated to be present in 1% to 4% of children,” according to the vision screening guidelines.

Joining the American Academy of Pediatrics, and in another effort to detect amblyopia and its risk factors, the U.S. Preventive Services Task Force now recommends at least one vision screening be performed on all children between the ages of 3 and 5 years.

According to Daniel E. Neely, MD, head of the AAPOS Vision Screening Committee,the guidelines address the urgency of screening children as young as possible.

“We know that the effectiveness of amblyopia therapy decreases after the age of 5; therefore, the new recommendations maximize the opportunity to diagnose amblyopia in the very youngest children when it is most amenable to treatment,” he said.

In support of the new guidelines, the article published in the Journal of AAPOS said amblyopia screening should begin in infancy and be a continuous process that occurs throughout a child’s visual development.

The updated guidelines also lower the referral rate for children by raising the threshold referral values.

“We recognize that this will produce a corresponding decrease in sensitivity to detect low-magnitude refractive pathology (and probably mild amblyopia) but anticipate that it will minimally affect the sensitivity to detect those high-magnitude refractive errors that are potentially most likely to lead to amblyopia,” the authors said in the Journal of AAPOS.

The original guidelines were updated to remove ptosis as an amblyopia risk factor due to the majority of amblyopia-related ptosis occurring in the situation of superimposed anisometropia.

According to Hunter, amblyopia is the No. 1 cause of monocular vision loss in children, even though amblyopia is preventable with early detection and treatment.

“Pediatricians do not have the tools or the time to perform vision screening properly during every well-child visit, and as a result, half of all children with amblyopia go undiagnosed before school age,” he said.

Automated screening vs. traditional screening

Instrument-based screenings are most commonly used to assess risk factors that could produce amblyopia, and traditional vision screening using visual acuity charts measures the presence of impaired vision, according to Neely

Traditional vision charts are ideal for older children who will follow directions and not make an attempt to memorize the letters in order to perform well on their vision test, Hunter said.

Photoscreeners analyze a refractive error-dependent crescent, meaning the device can identify, based on refractive error, children who are at risk for amblyopia.

According to Erin D. Stahl, MD, an OSN Pediatrics/Strabismus Board Member, pre-verbal, uncooperative or developmentally delayed children will benefit the most from photoscreening.

“Instrument-based vision screening devices can augment a traditional screening and provide a fast and accurate assessment of risk factors,” she said.

In addition to instrument-based screenings and traditional screenings, AAPOS has created an official vision screening kit that incorporates recommended versions of optotypes into visual acuity charts.

The kit uses Lea symbols and an HOTV chart, which can be paired with a matching card to use with children who cannot or will not talk, Neely said.

According to Robert W. Hered, MD, a leading expert on vision screenings who specializes in pediatric ophthalmology at Eye Physicians of Central Florida, over-referral is a potential disadvantage of instrument-based screenings.

“There is a tendency for manufacturers to set their instruments at high sensitivity levels, causing many young children with minimal refractive errors to unnecessarily fail screening,” Hered said. “This disadvantage has more to do with the implementation rather than the technology itself. The newer instruments do allow for reduction of over-referrals by adjusting their screening failure parameters, but this often requires local ophthalmologists to give specific guidance to pediatricians using the devices.”

Potential barriers to automated screenings

According to Hunter, the largest barrier between pediatricians and pediatric ophthalmologists is an understanding of the importance of early detection and treatment of amblyopia.

He said pediatricians must perform an entire well-child visit and vision screening in the same amount of time an ophthalmologist has with a child to check just vision.

“Many children are referred for costly and unnecessary eye examinations because of faulty screening or because the pediatrician just isn’t sure if there is a problem or not,” Hunter said. “If we can have faster and more accurate screening, then we can reduce unnecessary referrals.”

Education, training and ensuring all pediatricians have the necessary tools for vision screening will be the most important factors in completing successful screenings, he said.

According to the policy statement, another large barrier is the cost of the screening instruments.

“The instruments themselves often cost thousands of dollars, in addition to the costs of printers and supplies for each test performed,” the statement said. “There are additional indirect costs, including space and staff time required to perform these tests, as well as physician time to interpret them.”

Reimbursement for screenings

The Patient Protection and Affordable Care Act assures that vision screenings for young children are covered by all non-grandfathered insurance companies as part of a pediatric well-child visit, according to the American Academy of Pediatrics Department of Federal Affairs.

This mandate will allow pediatricians to be reimbursed for vision screening, Hunter said, with the hope of private payers covering the same fees the government payers are covering.

“The hope is that pediatric practices will embrace the new technologies and the insurance payers will embrace the new technologies because all these things seem to be coming at the right time where we now have instrumentation that allows physicians to do preschool vision screenings, as well as a mandate to actually perform the screenings,” Donahue said. “Potentially, my concern is that this will become another unfunded mandate by the government that the primary care doctors will have to deal with.”

According to Hered, photoscreening CPT code 99174 was given a relative value unit of 0.69 in 2008, with the adequacy of the RVU dependent upon the cost of the automatic screening device.

“With this new policy statement, in combination with the photoscreening CPT code, the hope is that photoscreening will become a regularly reimbursable activity for primary care physicians,” Hered said.

Although a CPT code is available for photoscreeners, this does not guarantee reimbursement from third-party payers.

“Historically, when such codes increase in frequency, third-party payers simply cease paying them. Additionally, vision screening is often inappropriately bundled into a global fee for the health maintenance visit, despite the fact that this is a separately identifiable service with real costs and established RVUs,” according to the guidelines. “The adoption of any such technology will be highly dependent on the payment decision of third-party payers. Primary care physicians will likely be slow to adopt these new technologies, despite their merit, if they are expected to absorb the cost without adequate payment for their up-front costs and their time.”

Echoing Donahue’s sentiment, Neely said his hope is that the mandate will not only allow more children to be screened, but also allow more physicians to be reimbursed.

“By paying for it separately from the routine primary care office visit, more providers will be willing and able to provide the service, and I expect that there will be a significant increase in the early detection of amblyopia and amblyopia risk factors,” Neely said. “This will save vision in children and help prevent lifelong impairment of one or both eyes.”

Vision screening technologies

Based on refractive error, photoscreeners and refractors can identify children who are at risk for amblyopia; however, unlike visual acuity tests, photoscreeners do not detect amblyopia, and neither vision charts nor photoscreeners can detect strabismus, Hunter said.

In response to this, Hunter and colleagues have developed a prototype device, the Pediatric Vision Scanner (to be marketed by REBIScan), which can detect strabismus and decreased stereopsis through a 5-second binocular retinal scan that detects bifoveal fixation, he said.

Clinical trials of the device found high accuracy in both sensitivity and specificity, he said, and results of the trials were presented at the 2012 AAPOS annual meeting.

Hunter said the device is going through safety testing in anticipation of applying for approval from the U.S. Food and Drug Administration.

Many of the automated vision screeners obtain measurements in less than 1 second.

Donahue said he believes that eventually automated vision screenings will be performed routinely by a nurse as part of a child’s intake to the pediatrician’s office, with a referral already made or known about before the pediatrician even sees the child.

Results of guidelines

According to Arnold, addressing amblyopia detection will be the largest benefit of the guidelines.

“With widespread adoption of photoscreening by pediatricians and children’s medical clinics, many more cases of amblyopia will be detected early enough for therapy to be effective,” Arnold said. “When [disease is] detected early enough, many children can be treated with consistent spectacle therapy and may avoid patching or strabismus surgery. Manufacturers will have motivation to produce even more valid, practical and child-friendly objective vision screening technology in the near future.”

Donahue said he is looking forward to the additional technologies the guidelines will potentially introduce.

“I hope these new guidelines will encourage companies that are developing these technologies to continue their development and continue to support their research to make these the best methods of evaluating children’s vision that are out there,” Donahue said.

Stahl said the guidelines may not be enough to alter current practices.

“I do not think that the guidelines alone will change the current practice of vision screening,” Stahl said. “There are many pediatricians who have chosen to invest in this technology for their patients. There are others who continue to perform traditional screenings and provide high-quality care. Ultimately, I see that reimbursement will drive whether instrument-based testing is available to a greater percentage of the pediatric population.”

According to Hunter, the guidelines, alongside new technologies and the potential for reimbursement, may offer an opportunity for more children to retain their vision.

“Pediatricians have an enormous responsibility to care for every aspect of a child’s health and welfare during a well-child visit. Due to lack of time, expertise and technology, failure to test for amblyopia and strabismus effectively has resulted in needless and permanent monocular vision loss in many millions of children,” he said. “If pediatricians can be reimbursed to perform instrument-based screenings using the best-available technology, it will make it possible for them to get the job done. The result, if the policy is sustained and further enhanced to promote annual vision screenings using current and future instruments designed for this purpose, we may see a day when amblyopia and strabismus are no longer able to silently steal the sight of our children.” – by Ashley Biro

How will the recent joint endorsement of instrument-based pediatric vision screening in preschool-aged children affect referrals to pediatric ophthalmologists for full workup for amblyopia?

Referrals may increase due to false positives

The guidelines will create a moderate to robust increase in referrals because pediatricians who do not have these instruments do not have the technology to be more accurate on when to refer. While these instruments have both false negatives and false positives, it is better to err on the side of referral than err on the side of not referring because 4% of children have amblyopia, and you do not want to miss that.

Also, if you see a child in your office and it is one of these false negatives or false positives and the child has a normal eye examination, often insurance companies will not cover routine eye exams. And, if an insurance company does not cover a routine eye exam, then the patient/family is going to be responsible for payment.

So in our office, we make it very clear to the family when they are referred by a pediatrician for a failed vision screening, whether it is by reading an eye chart of a slightly older child or an instrument-based reading of a younger child, that if the exam is normal and their insurance company does not cover routine exams, then they have to be responsible for payment.

While there may be a moderate to robust increase in referrals, some of these referrals will turn into normal eye examinations because the instrument-based systems are not perfect and they are not 100% accurate.

Robert S. Gold, MD, is the OSN Pedatrics/Strabismus Section Editor. Disclosure: Gold is a consultant and equity shareholder for PediaVision.

Increased referrals means increased detection of amblyopia

Technological advances continue to not only help us treat eye diseases better but also to detect them earlier. Given the limited window of opportunity to best treat amblyopia, advances which allow earlier detection are important. The recent joint American Academy of Pediatrics/AAPOS endorsement of instrument-based pediatric vision screening in children at younger ages is an example of how we are embracing new technology that can help us detect amblyopia in very young children.

This new technology will allow primary care providers to screen younger children with greater accuracy than has been possible in the past. This will mean more screening exams will be performed and more referrals to ophthalmologists will be made. Because no screening test is perfect, some of those referred will be a result of a false positive error.  The numbers of false positive exams will likely increase as younger and less cooperative children are screened. 

However, this increase needs to be viewed relative to the other potential options. Screenings in older, more cooperative children will carry the risk of failing to discover amblyopia in time to provide the best outcome. A full examination in all younger children is both cost prohibitive and unrealistic given the manpower required.  While implementation of this endorsement will lead to more referrals, it represents an improvement in our ability to detect and treat amblyopia in young children.

Scott E. Olitsky, MD, is an OSN Pediatrics/Strabismus Board Member. Disclosure: Olitsky has no relevant financial disclosures.