Measurement of stereoacuity outcomes at ages 1 to 24 months: Randot® Stereocards

Purpose: The aim of the present study was to develop a simple, quick, and portable random dot stereoacuity test for measurement of binocular sensory outcomes during the first 24 months of life. Methods: Vertical bar random dot vectographs were adapted for presentation in a “Teller Acuity Card” format, called the “Randot® Stereocards.” A forced-choice preferential looking protocol was used. Study participants included 386 healthy, term infants and children (normative cohort; age range: 1 month to 8 years) and 280 patients with common pediatric ophthalmic disorders (patient cohort; age range: 5 months to 9 years). Results: Overall, the success rate for test completion in the normative cohort was 91.3%. By 4 months of age, normal infants' mean stereoacuity was about 600″ and, by 6 months, 200″. Mean stereoacuity further improved to about 100″ by 12 months and 70″ by 18 months. Normative results were similar to published data obtained with laboratory-based stereoacuity tests. Randot® Stereocard data from normal children aged 2 to 6 years were similar to published normative data for the Preschool Randot® Stereoacuity Test. In the patient cohort, concordance between the Randot® Stereocards and the Preschool Randot® Test was 87%; concordance between the Randot® Stereocards and the Randot® Test was 84%. Conclusion: The Randot® Stereocards provide a simple, reliable, and valid method of obtaining a quantitative assessment of binocular vision in children up to 24 months of age for use in clinical trials and in clinical management.