Amblyopia and Visual Development

Background: Amblyopia, ‘lazy’ eye is a unilateral or bilateral reduction in vision for which no organic cause is present by physical examination of the eye with a prevalence of approximately 3.5% of the childhood population. It is commonly associated with a strabismus, refractive error or both. The most common form of treatment is conventional occlusion (daily patching the good eye). Clinical studies have attempted to investigate the optimal treatment of the disease and investigate compliance, however an evidence-base for treatment is still incomplete. Methods: The study included (i) a retrospective study of 322 amblyopic children to assess current visual outcomes in comparison to clinical effort and costs; (ii) A randomised control trial (n=52) comparing prescribed treatments of 0-hours, 3-hours and 6-hours patching per day in which compliance was electronically recorded; (iii) interviews of 25 families to explore reasons behind poor compliance; and (iv) a pilot study of educational material to improve compliance. Results: Current outcomes of amblyopia treatment are mediocre at considerable financial and time-costs. The RCT revealed poor compliance in both patching groups (3-hours and 6-hours) leading to visual improvements that were not significantly better than no patching. However, there was a clear dose-response between visual improvement and effective hours patched (p=0.00013). The interviews demonstrated emotional distress in families, lack of social acceptance, and confusion about amblyopia, its treatment and the role of professionals. Early findings indicate that an educational intervention could reduce the number of poor compliers. Conclusion: Poor compliance leads to poor visual outcomes of occlusion treatment for amblyopia. However, objective monitoring of patching demonstrates that occlusion therapy is effective. An educational intervention could address some of the problems associated with poor compliance such as poor parental understanding, providing feedback of visual improvement to the family and strategies for implementing patching as a normal routine.