Ocular predictors of the onset of juvenile myopia

PURPOSE. The purpose of this study was to identify reliable predictors of t he onset of juvenile myopia. METHODS. The data from 554 children enrolled in the Orinda Longitudinal Stu dy of Myopia (OLSM) as nonmyopes with baseline data from the third grade we re evaluated to develop a predictive profile for later onset of juvenile my opia. Myopia was defined as at least -0.75 D of myopia in the vertical and horizontal meridians of the right eye as measured by cycloplegic autorefrac tion (n = 45 children). Chosen predictors were refractive error and the ocu lar components: corneal power, Gullstrand crystalline lens power, and axial length. Sensitivity and specificity were calculated. Receiver operating ch aracteristic (ROC) curves were generated to evaluate and compare these pred ictors singly and combined. RESULTS. Refractive error, axial length, Gullstrand lens and pod corneal po wer n ere all significant predictive factors for the onset of juvenile myop ia. The best single predictor of future myopia onset in the right eye was t he right eye's cycloplegic autorefraction spherical refractive error value (mean sphere across 10 readings) at baseline. For a cut point of less than +0.75 D hyperopia in the third grade, sensitivity was 86.7% and specificity was 73.3%, The area under the ROC curve for this mean sphere was 0.880. Pr oducing a logistic model combining mean sphere, corneal power, Gullstrand l ens power, and axial length results in a slight improvement in predictive a bility (area under the ROC curve = 0.893). CONCLUSIONS. Onset of juvenile myopia can be predicted with moderate accura cy using the mean cycloplegic, spherical refractive error in the third grad e. Measurement of other ocular components at this age improves predictive a bility, albeit incrementally. Further improvements in the prediction of myo pia onset will require the use of longitudinal data in addition to one-time measurement of refractive error and the ocular components.