Preventing Infancy Blindness withPhotoscreening

Sophia Hussein

A research paper for PSY 440 (Perception)
Stephen F. Austin State University

 

Poets have strived to capture its beauty in words. Artists havetoiled with brushes in hand to create mere testaments to its glory. Still, most take it for granted as an inherent birth right. HelenKeller once was quoted to have said, "The most pathetic person in theworld is someone who has no vision."

Millions of newborns are unduly robbed of their sight each year asa result of amblyogenic, media opacities, and other treatable oculardiseases (Hartmann, 1998). Performing vision screening in newbornsis substantially difficult as they are unable to provide subjectiveresponses that traditional vision testing requires. Ocularalignment, a measurement of the positions of the optical and visualaxes of both eyes, is also not easily tested as infants do not easilycooperate (Atkinson & OJ, 1984). The necessity for a methodsuitable to newborns gave rise to a vision screening technique calledphotoscreening.

The photoscreening methodology is simple: a flash photograph ofthe subject's eyes is taken. The light reflected from the retina isanalyzed to detect refractive errors, strabismus, and mediaopacities. Other than having to fixate on the appropriate targetlong enough for the photoscreening, little cooperation is needed fromthe infant. Data are then analyzed by the evaluator, reviewingcenter, or computer for amblyogenic factors, which include:hyperopia, myopia, astigmatism, anisometropia, ocular misalignment,and media opacity. Positive findings are noted, and infants who donot pass the test may be referred for a complete eye examination(Ehrlich, Reinecke, & Simons, 1983).

Currently, the technique commonly administered for infant visiontesting is called non-cycloplegic retinoscopy. Non-cycloplegicretinoscopy involves using a lighted instrument called anophthalmoscope to study the retina of the eye. This method does notinclude paralysis of the ciliary muscle, otherwise known as paralysisof accommodation (Maino, Cibis, & Cress, 1984). The argumentamongst many in the pediatric community, namely the American Academyof Pediatrics (AAP), is that photoscreening may likely provide ahigher percentage of identifying ocular diseases in infants comparedto non-cycloplegic retinoscopy (AAP, 1996). Several studies havebeen conducted to determine the sensitivity and specificity of usinga computer-photoscreen and non-cycloplegic retinoscopy in thedetection of amblyopiogenic factors in varying numbers ofinfants.

In 1995, as reported in an article online about comparison ofcomputer-photoscreening with non-cycloplegic retinoscopy, the EyeResearch Institute and University of Medical Sciences in Chinaconducted a study that compared sensitivity and specificity resultsof the two techniques. Three hundred children, nine to fifty monthsold, were screened with a blinded standardized clinical assessment asthe standard. Photoscreen images on the computer monitor screen werereviewed and analyzed immediately by two independent observers forindicators of amblyopiogenic risk factors. Simultaneously, theresults were compared to the findings of a full ophthalmologicexamination.

After the study was complete, it was found that thecomputer-photoscreener displayed a sensitivity of 94.6% and aspecificity of 90.1%, while the non-cycloplegic retinoscopy resultedin sensitivity and specificity of 85.7% and 81.0%, respectively. Theconductors of this study, in the article of an online aboutcomparison of computer-photoscreening with non-cycloplegicretinoscopy, concluded that the computer- photoscreener offered anincreased opportunity to identify problems that limit vision, andcould provide a feasible and sufficiently reliable screeningtechnique in infants to be screened successfully for amblyopiogenicrisk factors.

A similar study, reported in another online article on screeningfor amblyogenic factors on a kidsight.co., was conducted two yearslater by the Medical Technology and Innovations Incorporation (MTI)in Tennessee. The main purpose of the study was to describe theresults from a statewide preschool vision screening program using theMTI PhotoScreener. Participants included a total of 15,059 childrenaged 6 to 47 months who were enrolled in childcare and preschoolsettings throughout the state of Tennessee. Volunteers from thelocal Lions Clubs took photoscreening photographs of children thatwere later interpreted at the Vanderbilt Ophthalmic PhotographyReading Center using predetermined criteria. Children who failed thescreening were referred to community ophthalmologists or optometristswho performed a comprehensive evaluation and forwarded the results tothe authors.

The article states that during the 2 years of the screeningprogram, 15,059 children were screened in 850 screenings. Thescreening referred 1013 children (6.7%), and 704 photographs (4.7%)were unreadable. Of the 531 cases where adequate follow-up resultswere reported, 320 included cases where children who failed thescreening had a significant abnormality (strabismus, anisometropia,high hypermetropia, high astigmatism, or high myopia).

The findings of the studies are most useful when translated intolayman's terms. By comparison to current practices, photoscreeninghas proven to be more likely to identify abnormalities in newbornsthat could later result in blindness. When administered andinterpreted by qualified technicians, it could literally save thesight of countless infants. Essentially, it becomes a matter oftiming. The sooner more research can be conducted proving theefficacy and necessity of photoscreening, the more infants that canbe spared a lifetime of darkness. The AAP favors additional researchof photoscreening devices and other vision screening methods inlarge, controlled studies to elucidate the validity of results,efficacy, and cost-effectiveness for identifying amblyogenic factorsin different age groups as well as subgroups of children (AAP,1996).

Also recognizing an inadequacy in current infancy screeningprograms, the U.S. Congress urged the Maternal and Child HealthBureau in the Health Resources and Services Administration to consultwith the National Eye Institute of the National Institutes of Health,Department of Health and Human Services, and various national andstate agencies, to determine useful screens to competentlydistinguish amblyopia risk factors and other significant problems and to supply and assess the practicality and efficacy of ocularscreening services for young children, including photoscreeningtechnology. As a result of this recommendation, an expect panelconvened in September 1998, and a report from this panel was releasedin May 1999 (Hartmann, 1998).

A major conclusion of the expert panel's deliberations was thatphotoscreening represented one of the most dramatic developments inthe history of preschool vision screening. The panel believed thatthis technique could be applied in early infancy and opened up thepossibility of detecting risk factors in a "latent" period before theonset of amblyopia itself. Photoscreening was shown to have severaladvantages over conventional screening techniques. Most notably, theease with which difficult-to-test individuals could be approachedcompared to typical recognition acuity tests and the resultingphotographs (or video images) providing a quantifiable objectivemeasure (Hartmann, 1998).

Taking into account the recommendations of both the expert paneland AAP, it is apparent that extensive research needs to be conductedto illustrate the full benefits of photoscreening. This research canbe funded by the government or can be raised by concerned citizens incommunities nationwide.

An excellent example of involvement from the private sector is theestablishment of the Children's Eye Photoscreening Program by theLion Club International Foundation. The foundation allows itsmembers to work with local eye care professionals and institutions tohelp make a measurable impact on preventable blindness amongchildren. Members visit day care centers, nursery schools, and otherlocations where young children are located and photograph each childusing the MTI PhotoScreener. Following interpretation by qualifiedtechnicians, children whose photographs show signs of amblyogenicfactors are referred to partnering eye care providers in their owncommunity for further examination and possible treatment (Departmentof Health and Human Services, 2001).

The Louisiana Cubsight Program also actively helps to reduce theincidence of amblyopia in pre-school children. Volunteers aretrained to utilize the MTI Photoscreening camera to screen pre-schoolchildren in Day Care Centers, Headstart Programs, andprivate/parochial schools across Louisiana. Since July 1, 2001, theCubsight Program has screened over 13,130 children and referred over720 children to local eye doctors for complete eye exams (Departmentof Health and Human Services, 2001).

The future of ending needless infancy blindness is bright, withthe pediatric community quickly recognizing the unequivocal potentialafforded by photoscreening. However, several smaller goals must beaccomplished before the ultimate goal of producing the most efficientand reliable screening technique to data can be achieved. First,technicians must be educated to properly administer and interpretresults. Next, the government and private sector can be petitionedfor the funds necessary to conduct additional research ofphotoscreening devices in large, controlled studies. Finally, theresults of all such studies can jointly provide for a comprehensivevision screening technique that is unique in its efficacy andcost-effectiveness for preventing infancy blindness.

It is without question that a society must constantly seekprogression to ensure the survival of its people. Technologicaladvancements have led to a perpetually increasing and improvingquality of life. Still, some principles are inherent in a society,regardless of how advanced or archaic it may be. This universaltruth is manifested in the responsibility of a community to thoseamong them most innocent, helpless, and pure.

References

American Academy of Pediatrics. (1996). Eye examination andvision screening in infants, children, and young adults. Pediatrics,98,153-157.

Atkinson, B., & OJ, D.K. Et al. (1984). Screening forrefractive errors in six to nine month old infants byphotorefraction. Brit J Ophthalmol, 68,105-112.

Department of Health and Human Services. (2001). RetrievedNovember 20, 2003, from http://www.healthyvision2010.org/exams/preschool.htm#cepp

Ehrlich, M.I., Reinecke, R.D., & Simons, K. (1983). Preschoolvision screening for amblyopia and strabismus: programs, methods,guidelines. Surv Ophthalmol, 28, 145-63.

Hartmann, E.E., (Ed). (1998). Vision Screening in the PreschoolChild. US Department of Health and Human Services.

Maino, J., & Cibis, G., Et al. (1984). Non-cycloplegic versuscycloplegic retinoscopy in preschool children. Ann Opththalmol, 16,880-882.

Screening for amblyogenic factors using a volunteer lay networkand the MTI photoscreener. (2000). Retrieved November 20, 2003, fromhttp://www.kidsight.co.il/article6.doc


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