PEDIATRICS Vol. 107 No. 4 April 2001, pp. 809-809

How Young Is Too Young for Amblyopia Screening?

To the Editor.

Kemper et al¹ reviewed studies of available screening tests for amblyopia. Articles in the Medline database from 1966 through January 1999 were searched; 4 articles were included in the final analysis. We read the findings with great interest and offer the following for further discussion.

Our 1988 study² satisfied the inclusion criteria for "high-quality studies" in which: 1) all participants received an ophthalmologic examination, 2) the examiners and screeners were masked from one another's findings, and 3) screening failure criteria were defined. Nonetheless, our study was excluded, presumably because the average age of the children in our study was 18 months, while Kemper et al included only studies where the study population had an average age between 2 and 5 years old.

One major advantage of photoscreening is the ability to screen younger children than can be screened by most other methods. In contrast to traditional Snellen or other acuity-based screening, photoscreening can be done as early as infancy. Early detection of amblyopiogenic factors allows for early treatment. For these reasons, we took on the challenge of evaluating a commercial photoscreening system in children 3 years old. Although the age limits imposed by Kemper et al may be appropriate for acuity-based screening, we recommend that the lower limits of the age requirement be eliminated for photoscreening or other methods that are suitable for screening younger children.

We applaud the authors' recommendation that vision screening tests be tested in primary care settings, a goal our study worked toward.² Three of the 19 photograph graders in our study were primary care pediatricians. We examined the ability of pediatricians, pediatric ophthalmologists, and other health care professionals to grade photoscreening photographs. Variability in sensitivities and specificities among graders was wide,^2,3 indicating inconsistent photograph interpretation skills or deficient screening guidelines or both.

In summary, one major attraction of photoscreening is the ability to provide vision screening to preverbal children. Testing of photoscreening and other vision screening modalities should include primary care settings. Kemper et al described important criteria against which future vision screening studies are to be judged.

Patrick Tong
Wilmer Ophthalmologic Institute
Johns Hopkins University, School of Medicine
Baltimore, MD 21205

Juanita Stumpp Loftus
Department of Pediatrics
Kaiser Permanente Medical Center
Mountain View, CA 94041

REFERENCES

1. Kemper AR, Margolis PA, Dows SM, Bordley WC A systemic review of vision screening tests for the detection of amblyopia. Pediatrics. 1999; 104:1220-1222 [Abstract/Free Full Text]
2. Tong PY, Enke-Miyazaki E, Bassin RE, Screening for amblyopia in preverbal children with photoscreening photographs. Ophthalmology. 1998; 105:856-863 [CrossRef][Medline]
3. Tong PY, Bassin RE, Beauchamp GR, Screening for amblyopia in preverbal children. Ophthalmology. 2000; 107:2-4 [CrossRef]

In Reply.

I would like to thank Drs Tong and Loftus for their comments regarding our review of vision screening for the detection of amblyopia. They are correct in that their study¹ was excluded because it focused on children younger than 2 years old.

Photoscreening can be used to evaluate very young children. Indirect evidence supports the notion that early detection of amblyopia leads to better treatment outcome.² Unfortunately, there is little direct evidence.

Amblyopia is a common and preventable disease. However, the optimum screening strategy, including method and timing, is unclear. There is a great need for pediatricians, ophthalmologists, and optometrists to work together to solve this important problem.

Alex R. Kemper
University of North Carolina
Department of Pediatrics
Chapel Hill, NC 27599-7225

REFERENCES

1. Tong PY, Enke-Miyazaki E, Bassin RE, Screening for amblyopia in preverbal children with photoscreening photographs. Ophthalmology. 1998; 105:856-863
2. Flynn JT, Schiffman J, Feuer W, Corona A The therapy of amblyopia: an analysis of the results of amblyopia therapy utilizing pooled data of published studies. Trans Am Ophthalmol Soc. 1998; 116:431-453