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Emerging technologies for vision screening must overcome resistance to reach to more children
Lack of industry support, legislative approval and reimbursement have slowed innovation in vision screening, researchers say. Part 1 of three parts.
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Pediatric vision screening has come a long way from the tumbling E exams in the school nurse’s office.
The late 20th century ushered in a pediatric vision screening movement led by visionary ophthalmologists, pediatricians and public health officials who took a stance on vision screening, wanting to screen all children for conditions such as amblyopia and strabismus at an early age.
Since that time, technological innovations and cutting-edge screening devices have emerged. The advent of the PhotoScreener (Eye Care International), a portable screening camera invented by Howard L. Freedman, MD, that photographs retinal images for remote interpretation, helped to propel the screening initiative by putting vision screening into the hands of lay people. Volunteers, nurses and childcare workers could screen preschool and preverbal children in daycare centers and preschools months or years before the child reached the school nurse’s office.
“It’s an accomplishment. When I look back and see where vision screening was years ago – just 10 years ago – we’ve come a long way,” said Sean P. Donahue, MD, PhD, a pioneer in the field of vision screening who has helped screen more than 140,000 children in his home state of Tennessee, at Vanderbilt University Medical Center’s Operation KidSight.
“The technology is exciting, but it’s still evolving,” agreed Robert S. Gold, MD, Pediatrics/Strabismus Section Editor for Ocular Surgery News. “Years ago, people were skeptical about how mass screenings were going to be done. Today, we know that screening works, and we need to do a great job of screening all children and do it at an earlier age, so that we can get [those who need it] into the doctor’s office for a comprehensive eye exam sooner.”
While progress has been made, proponents of vision screening continue to face obstacles and resistance in the quest to screen every child. To examine these controversies, Ocular Surgery News presents a three-part series on pediatric vision screening beginning in this issue.
The series will explore the factors that have prevented vision screening from becoming a nationwide practice and explain to readers what they can do at a local level to join the lobbying effort for better screening measures.
This first installment begins by discussing issues facing practitioners in large-scale screening programs, including some of the obstacles that have hindered the development of new technologies. Following this, we review some of the established and emerging vision screening technologies to help prepare general and pediatric ophthalmologists to incorporate vision screening measures into their clinics and their communities.
Subsequent articles in the series will address the range of current and proposed state legislation regarding photoscreening and the pluses and minuses of some of the current and pending screening technologies.
Obstacles ahead
“So much of what we do as screeners depends on industry support, on legislation and health care providers backing us and supporting this cause. It’s a slow struggle,” Robert W. Arnold, MD, vision screening chairman of the American Association for Pediatric Ophthalmology and Strabismus, told Ocular Surgery News.
While public service screening projects such as Dr. Arnold’s in Anchorage, Alaska – which has helped screen 20% of Alaskan children through the Alaska Blind Child Discovery project – accomplish a lot on their own, they still struggle to survive.
“The contributions that we receive from Lions Clubs International are wonderful, but they are limited. There is not a bottomless source of funds,” Dr. Donahue said.
“The problem is that no one is on the same page when it comes to vision screening,” said David B. Granet, MD, of the University of California, San Diego’s public screening project and co-developer of the EyeDx photoscreening system. “We need a united voice.”
Dr. Granet said that while ideas and innovations abound, technologic advancement is slowed due to factors that include hesitation from lawmakers, lack of adequate reimbursement for vision screening and disagreement among ophthalmologists themselves.
“Resistance is brought on by ophthalmologists who may agree on screening children but differ on what age to screen, how often, and what characteristics are desirable in a screening tool. While everyone is taking time out to decide what to do, people aren’t screening and, month by month, children are being missed,” he said.
VIP study to find answers
The Vision In Preschoolers (VIP) study, a multicenter project sponsored by the National Eye Institute now planning a third phase, was developed to address some of the questions that physicians, optometrists, vision researchers, industry and academicians have pertaining to vision screening.
“Lots of different screening procedures are being used in different parts of the country. Some states mandate screenings but didn’t specify what type; others didn’t even mandate them. People just wanted to bring a broader perspective and increased scientific rigor to the question of screening preshoolers,” said Graham E. Quinn, MD, MSCE, a member of the VIP executive committee.
In the study, several vision screening tools, including autorefractors, photoscreeners, cover testing, and assessment of visual acuity and stereopsis, have been evaluated to determine which are the most accurate, easiest to use and most effective instruments. The first phase of the study tested the screening methods as used by ophthalmologists and optometrists, a second phase evaluated the efficacy of those tests when administered by pediatric nurses and lay screeners, and the next phase will judge how well the best screening instruments work in different settings on a more general population.
“Phase 3 is, essentially, where the rubber hits the road,” Dr. Donahue said. Since vision screening is meant ideally to be carried out by nonphysician health care workers and the general public, phase 3 of the VIP study will shed some light on the accuracy and efficacy of mass screenings by the general public, he said.
Results may help vision screening advocates approach legislators and key decision-makers to move the screening movement forward, others said.
“A major factor in turning things around will be when the government gets involved, and when providers can bill for screening,” Dr. Freedman said.
Currently, providers who do photoscreening and send camera images in to a central reading center for interpretation can bill for interpretation with code 92285. However, the actual act of photoscreening a patient falls under code 0065T, an “emerging technology” code that carries no reimbursement.
“As soon as legislation is behind us, and physicians are reimbursed, technology companies will line up to help. And they will do a better job than all of us combined,” Dr. Arnold said.
Public health approach
Not all ophthalmologists think that photoscreening with remote diagnosis is the best approach to mass vision screening. Herve M. Byron, MD, suggests that a standard protocol should be followed to ensure the maximum number of children will be accurately and cost effectively screened by the appropriate personnel while still allowing instantaneous results.
He said that screenings should be performed only by health care professionals, such as school nurses or eye technicians, using rapid, child-friendly devices that would allow immediate retesting if the accuracy of the first test is in doubt. The testing instrument should have a high degree of sensitivity to reduce false positives, he added.
Instead of remote diagnosis, Dr. Byron said the protocol should refer any child who tests positive for any ocular abnormality for further examination by a qualified professional to determine the extent of the problem and type of treatment required.
He also said reimbursing for the screening itself may not be the best use of resources.
“I strongly oppose any reimbursements for the initial screenings,” Dr. Byron said. “This is a public health problem and should be treated as such,” he said. “When senior citizens are tested for high blood pressure, glaucoma or diabetes by such organizations as the Lions, no fees are incurred. The same approach should be used for this type of screening.
“I also strongly oppose paying for a photograph to be read at a separate location than where the test was performed. This system would create ... a high percentage of false positives and incur unnecessary costs,” Dr. Byron continued.
“The eye care professional who examines those children with abnormal screening results is reimbursed for their diagnosis and treatment. This will ensure that only those children who actually require glasses will be given them,” he said.
Resistance to photoscreening
Resistance to photoscreening, like many new technologies in medicine, has existed from the start.
“There was slow acceptance among pediatricians and pediatric ophthalmologists for screening early and photoscreening. It took a while for me, and others, to get approval,” Dr. Freedman said.
“I hit brick wall after brick wall. No one wanted to talk to me about the PhotoScreener, but I was convinced of the technology,” said Jeremy P. Feakins, president and chief executive officer of Medical Technology and Innovations (MTI), the company that developed and marketed the PhotoScreener throughout the 1990s.
Dr. Freedman brought the concept of photoscreening to the United States from Europe in the 1970s after seeing an early photoscreening prototype from Finland, developed by Keri Kakinen, MD. Believing in Dr. Kakinen’s idea of using a photorefractor to image the retina with flashes of light, Dr. Freedman and Mr. Feakins developed the PhotoScreener.
“The PhotoScreener tries to approximate the effect of retinoscopy, and it does it in an instant, with someone who doesn’t know anything about it,” Dr. Arnold said. “That was the beauty of the concept.” The off-axis camera produces an instant photograph, designed to be interpreted by an expert on site or at a central reading center. Trained interpreters detect refractive errors, eye misalignment and cataract using the film images.
In 1995, the device became available for commercial use and was marketed as the MTI PhotoScreener. The device went on to become the gold standard for photoscreening, although there has been controversy over its efficacy and its potential to over-refer or under-refer children for eye exams.
In October of last year, the device was acquired by ECI, a discount optical provider, according to the company’s president and chief executive officer, Clark Marcus. ECI plans to install the PhotoScreener in optical shops and provide screenings to its client base. Additionally, plans are under way to update the PhotoScreener to more modern digital technology.
Dr. Donahue was one of the first physicians to incorporate the PhotoScreener into practice and to study it in a large, randomized, multicenter trial. Initial results on 15,000 children screened were successful, and Dr. Donahue continues to use the PhotoScreener today.
“Of kids who are screened, 4% get referred for a comprehensive eye exam. Seventy-five percent of those children receive an exam, and, of this population, more than 70% of children have eye problems,” Dr. Donahue said. He noted that the referral rate for children who are screened and follow up with an eye exam is higher than the statewide immunization rate.
A collaborative and philanthropic effort involving Vanderbilt University, the Lions Clubs International, Operation KidSight, the Vanderbilt Ophthalmic Imaging Center, volunteers, community centers and donors has made Dr. Donahue’s project a model program for photoscreening initiatives throughout the nation.
Other photorefractors
Other technologies have been developed for screening purposes that enlist photorefraction, the technique behind the PhotoScreener. These include the iScreen (Digital Vision Screening Technology), a camera that digitally transfers images to iScreen Central Analysis for interpretation, and the EyeDx, a result-on-demand screener developed by Dr. Granet and his team of researchers at University of California, San Diego.
The EyeDx contains a digital camera that acquires the photoscreening image, interprets the image with computer software and then immediately prints out a “pass” or “refer” report on site.
Dr. Freedman called the EyeDx a “next-generation photoscreener.”
But the device is currently not available for commercial sale. Dr. Granet and colleagues formed the company EyeDx to market and distribute the technology, but they were forced to terminate the company due to lack of follow-up funding.
“Initially we thought that forming a company would be the quickest way to get automated photoscreening into the hands of people. But it didn’t work that way. In many ways our experience was similar to MTI; we hit brick walls,” Dr. Granet said.
Dr. Granet said it was difficult to survive in a market in which few agree on the best manner and method of vision screening, and with optometrists continuing to question whether comprehensive eye exams for every child, though nearly twice the cost of screening, might be more appropriate.
“We have to be very careful not to deny innovation amidst all the study,” Dr. Granet said. “While screening may get better in the future, and perhaps there are things needed to tweak the technology, let’s do something now.”
Dr. Granet and colleagues continue to use the automated photoscreening system in their city-wide screening initiative, which screens thousands of children in San Diego every year.
SureSight, autorefraction promising
Autorefraction is another form of vision testing that has been used in vision screening. Where photorefraction uses flashes of light to instantly image the retina, autorefraction utilizes infrared laser beams to continuously image the retina.
An autorefractor that has shown promise in the VIP study is the SureSight Vision Screener (Welch Allyn). The SureSight gives an immediate estimate of the refractive error, which can be used to give a “pass” or “refer” response in printout form. However, critics complain that the technology is less efficient than other screening devices because it takes only monocular photos.
“As a screener, the SureSight is quite good,” Dr. Arnold said. “It has a big advantage over most photoscreening right now in that the answer occurs on site. There is no need to send photos out for interpretation,” Dr. Arnold said.
For large community-based vision screening programs like Dr. Arnold’s or Dr. Donahue’s, not needing a central reading center is a big advantage, both economically and logistically. Dr. Donahue has already screened more than 2,000 children with the SureSight.
“We plan to screen about 4,000 children with the SureSight and present the results at the Association for Research in Vision and Ophthalmology meeting this spring,” Dr. Donahue said. “So far, the device tends to refer more children than the PhotoScreener would.”
Dr. Donahue has based his specificity and sensitivity for the SureSight on the referral criteria outlined by researchers in the VIP study, who adjusted the Welch Allyn guidelines for the SureSight and have found them to be well-validated in the study.
A second autorefractor that is also being tested in the VIP study is the Retinomax K-plus 2 (Nikon Inc. Instrument Group).
A study appearing in August in Optometry and Vision Science, led by G. Steele, MD, found the Retinomax and SureSight “to agree with each other and with the results of cycloplegic retinoscopy for determining sphere and cylinder. Results suggest that either device may be useful only as a screening tool for assessing refractive error in preschool children.”
On the horizon
Another next-generation screener in development is from Wavetec Vision Systems. The Wavetec screener is designed to detect amblyopia and strabismus in children 3 years of age or older by employing wavefront technology.
“The device is stable, easy to get the children to comply with and yields accurate, consistent results with very few false positives,” said Dr. Byron, a principal investigator in the Wavetec clinical trials. The Wavetec system is not yet available for commercial use but may be available this year, according to company officials.
A second promising device is the Pediatric Vision Screener (PVS) developed by David Hunter, MD, PhD, and teams at Johns Hopkins University and Harvard Medical School.
“This device is different from other screeners because it doesn’t take a flash photograph or continuous image. It checks alignment, and only then will it fire,” Dr. Arnold explained.
The PVS was constructed on the principles of defocus and alignment. The camera uses binocular retinal birefringence scanning to determine when both eyes are aligned, and then scans the retina and records an image.
“This device doesn’t take a recording unless the eye is lined up – this is especially useful when trying to screen a wiggly little kid,” Dr. Arnold said.
Screening wiggly kids, especially wiggly babies, is one of myriad challenges in screening preschool-aged and preverbal children. One device that attempts to remedy this problem in children is the commercially available Enfant Pediatric Vision Testing System (Diopsys). The Enfant uses evoked potential technology to recognize neurological responses to stimuli.
For testing, sensory patches are placed on a child’s head and one eye is patched. Children are shown “attention-catching” images on a computer screen with character faces and music; a response is recorded and then a test outcome is presented on screen, identifying if a patient has passed or failed the screening. In a testing sample of 122 children, up to 5 years old, 94% of children accurately completed the exam and received an appropriate grade.
Subjective, conventional testing
Another computer-based screening measure is currently being developed by James W. O’Neil, MD, a pediatric ophthalmologist in Phoenix, Arizona. The software, called VisionQuest 20/20, allows young children — many of whom are more computer-savvy than their parents — to take a vision test on a computer screen by answering questions related to picture games.
With inventive computer games, neurological sensors, wavefront devices, photoscreeners and autorefractors emerging in the field of vision screening, it appears that the future of screening lies in technology. However, many practitioners still favor traditional subjective methods of screening, such as Teller acuity cards and HOTV eye charts.
Though tried-and-true, many say these methods are time-consuming and defeat the modern screening goal of catching as many at-risk children in as little time as possible, to expedite the process of diagnosing disease and initiating treatment before amblyopia sets in.
Approval brings innovation
Some experts question the efficacy of these old methods. “What we assume has been tested – traditional vision screening – has not, and what we assume has not been validated – photoscreening – has,” Dr. Freedman said. He said that, to date, there are no masked, prospective clinical trials in the literature that validate the accuracy of traditional vision screening as has been done with photoscreening and other new technologies.
“There is little scientific basis to traditional screening, yet few want to challenge the old ways,” Dr. Freedman said.
Dr. Granet agreed that existing common opinion and a strong desire for thorough validation is holding back innovation in the field.
“We shouldn’t let studies and stale technologies become the anchor that slows the development of any new projects,” he said. “Screening will not harm children. It’s not like surgery. If you wait forever for validation, the bar will never be met.”
However, what perhaps has slowed the progression of technology in vision screening lies more in the pockets of health care providers and industry than in the literature.
“If the government gets on board, industry will not be far behind,” Dr. Arnold said.
In the meantime, Dr. Granet said, “venture capital will not get involved in something they cannot make money in. Worse yet, any new technology may now require 5 years of multicentered study to satisfy some researchers before they concur with its efficacy. That also will scare away funding for innovation.”
“There are two areas that could potentially save this: if screening became a regular reimbursable code, and if screening gets onto the HMO’s HEDIS report card, a set of provider criteria required by federal law,” Dr. Arnold said. Only then, will investors open their wallets.
Indeed, screening technology has the potential to thrive under these measures. Experts say there could be a “technological boom” and the movement for vision screening could get on track.
“New technology will win this battle – as soon as it becomes reimbursed,” Dr. Arnold said.
For Your Information:
- Robert W. Arnold, MD, can be reached at Ophthalmic Associates, 542 W. Second Ave., Anchorage, AK 99501; 907-276-1617; fax: 907-278-1705; e-mail: eyedoc@alaska.net. Ocular Surgery News was unable to confirm whether Dr. Arnold has a direct financial interest in any products mentioned in this article or if he is a paid consultant for any companies mentioned.
- Herve M. Byron, MD, is a clinical professor of ophthalmology at the NYU School of Medicine, Department of Ophthalmology. He can be reached at 22 East 82nd St., No. 1, New York, NY 10028; 212-249-8494; e-mail: byronmd@mac.com. Dr. Byron has no direct financial interest in any products mentioned in this article. He is a paid consultant for WaveTec Vision Systems.
- Sean P. Donahue, MD, PhD, can be reached at Department of Ophthalmology, Vanderbilt University Medical Center, 8000 Medical Center East, Nashville, TN, 37232; 617-936-2020; fax: 615-936-1540; e-mail: sean.donahue@vanderbilt.edu. Dr. Donahue has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any companies mentioned.
- Jeremy P. Feakins can be reached at 1200 West Penn Grant Rd., Lancaster, PA 17603; 917-679-2005; e-mail: jfeakins@msn.com.
- Howard L. Freedman, MD, can be reached at 3113 Lake Sammamish Parkway NE, Sammamish, WA 98074; 425-868-0700; 425-785-1447; e-mail: freedmanh@earthlink.net. Dr. Freedman has a direct financial interest in the MTI photoscreener.
- Robert S. Gold, MD, can be reached at 225 W. State Rd. 434, Suite 111, Longwood, FL 32750; 407-767-6411; fax: 407-767-8160; e-mail: rsgeye@aol.com. Dr. Gold has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any companies mentioned.
- David B. Granet, MD, can be reached at the Shiley Eye Center, 9415 Campus Point Dr., La Jolla, CA 92039; 858-534-2020; fax: 858-534-5695. Ocular Surgery News was unable to confirm whether Dr. Granet has a direct financial interest in any products mentioned in this article or if he is a paid consultant for any companies mentioned.
- Graham E. Quinn, MD, MSCE, can be reached at the Wood Center, 1st Floor, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104; 215-590-2791; fax: 267-426-5015. Dr. Quinn has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any companies mentioned.
- Nicole Nader is an OSN Staff Writer who covers all aspects of ophthalmology, specializing in pediatrics/strabismus and neuro-ophthalmology.