Anisometropic amblyopia: factors influencing the success or failure of its treatment

Aim: To provide an overview of the factors that might influence the success or failure of anisometropic amblyopia treatment. Methods: A literature-based review was conducted using mainly Science Direct. Searches were restricted to English-based publications over the past 10 years, mainly focusing on children before they reach visual maturation. Results: The most common factors considered within the literature are patient age, the degree of anisometropia, the depth of amblyopia, and the type of treatment and its compliance. However, methodological differences could account for the reported differences in treatment outcome. Conclusion: There does not seem to be a general consensus on any factors that could determine why the success rate of anisometropic amblyopia treatment is not as high as expected. This could partly be due to varying definitions in the literature of anisometropia and the success of treatment; or simply the failure to separate strabismics from anisometropes, or hypermetropes from myopes. Potential factors that are not often considered include the presence of aniseikonia, astigmatism and the accommodation response in anisometropic amblyopes.