Screening for amblyopia in preverbal children with photoscreening photographs: II. Sensitivity and specificity of the MTI photoscreener.

OBJECTIVE

To determine the sensitivity and specificity of vision screening using the Medical Technology and Innovations (MTI), Inc., PhotoScreener.

DESIGN

Cross-sectional study. PARTICIPANTS AND TESTING: Three hundred ninety-two children less than 4 years of age received a complete ophthalmologic examination and were photographed using the MTI PhotoScreener. One hundred three children had normal examinations, and the remaining 284 children had conditions of interest for pediatric screening: ptosis, media opacity, refractive error, or strabismus. Five children were excluded.

MAIN OUTCOME MEASURES

The grading of the photographs by the manufacturer's representative was compared with the results of the ophthalmologic examinations. Sensitivity and specificity of vision screening were determined.

RESULTS

The analysis of all informative photographs resulted in a sensitivity of 65% and a specificity of 87%. The sensitivity of detection for children with some forms of strabismus was high, up to 95% for esotropia of 10Delta or more. Sensitivities for the detection of ptosis, media opacity, and refractive error were poor in patients where strabismus was not also present.

CONCLUSIONS

The MTI PhotoScreener may play a role in preverbal vision screening; identification of two of three children with amblyopiogenic factors before age 4 would be an exciting advance in public health. However, improvement in the ability to identify children with media opacity and refractive error is necessary. Improvements may be possible with modifications of the examination failure and photograph grading criteria.