Factors Influencing the Success of Treatment in Anisometropic Amblyopia

Purpose: To examine factors influencing successful resolution of amblyopia in children with hyperopic and astigmatic anisometropia presenting to a pediatric ophthalmology practice in London, Ontario. Methods: A retrospective chart review was conducted to identify children treated for hyperopic and astigmatic anisometropia from 2008-2016. 39 children ages 12 years and under with hyperopic and astigmatic anisometropia were included. Information regarding referral pattern, presenting findings and outcomes was collected. Presenting degree of anisometropia, compliance, age at presentation and initial visual acuity (VA) were all statistically analyzed to determine effect on final VA. Results: The mean age at referral to pediatric ophthalmology was 5.2 years. 47% presented with dense amblyopia, with the poorer eye having a VA of 6/30 or worse. 51% of children were successfully treated, with a final VA of 6/9 or better in the worse eye, and 5% of children had residual dense amblyopia. Presenting magnitude of anisometropia was the only factor found to have a significant effect on successful treatment, as for every one diopter decrease in magnitude of anisometropia, there was a 40% higher odds of achieving a final VA of 6/9 or better (point estimate 0.62, 95% CI 0.39-0.97, p=0.03). Age at presentation, presenting VA and compliance to treatment all had no significant outcome on treatment success. Conclusions: Magnitude of anisometropia was found to be the only significant factor that influences the final visual acuity of children, confirming the necessity for early detection of amblyogenic refractive errors.