|Title||WAS HIRSCH RIGHT? PREDICTION OF MYOPIA ONSET IN CHILDHOOD|
|Author, Co-Author||Karla Zadnik, Donald Mutti, Nina Friedman, Lisa Jones, Melvin Moeschberger|
|Abstract|| Purpose. The Orinda Longitudinal Study of Myopia was initiated in 1989. Unlike previous studies of myopia, it focuses on incident cases of myopia, seeking to predict new cases of myopia that develop in the Study period using measurements taken prior to myopia onset.
METHODS. Onset of myopia was defined as any one occasion where both meridians of the eye were at least -0.75 D myopic on cycloplegic autorefraction (Canon R-1). A sample was constructed, comprised of 554 children measured through fall 1994 with baseline data from third grade. Of these, 45 children have developed myopia since third grade. The predictive factor examined was mean cycloplegic sphere on autorefraction in third grade.
RESULTS. Among the 458 children with a cycloplegic mean sphere of +0.50 D or more hyperopia, only 14 of them subsequently developed myopia. Of the 96 children with a cycloplegic mean sphere of less hyperopia than +0.50 D, 31 went on to develop myopia (+0.50 D sensitivity = 68.9%, specificity = 87.2%). When examining a cut-off point of +0.75 D, 6 of the 379 children with a cycloplegic mean sphere of +0.75 D or more hyperopia developed myopia, and 39 of the 175 children with a cycloplegic mean sphere of less hyperopia than +0.75 D developed myopia (+0.75 D sensitivity = 86.7%, specificity = 73.3%). In 1964, Monroe Hirsch examined the predictive value of +0.75 D as a cutoff value (noncycloplegic retinoscopy) at age 5 or 6 years for predicting myopia (-0.50 D or more myopia spherical equivalent) and found sensitivity of 81.5% and specificity of 72.1%.
CONCLUSIONS. Cycloplegic autorefraction results in third grade provide slightly improved sensitivity and specificity for prediction of future myopia compared to Hirsch's Ojai data. However, if optical or pharmaceutical treatment of impending myopia becomes a reality, these levels of prediction may be unacceptable. Future analyses will determine the additional predictive value of measures of the ocular components. Supported by NIH-NEI gr
|Affiliation of Co-Authors||The Ohio State University College of Optometry, University of California, University of California, The Ohio State University College of Optometry|