Visual Outcome of Occlusion Therapy in Anisometropic Amblyopia

Mohammad Mostafizur Rahman

doi:10.61561/ssbj.v5i2.53

Authors

Mohammad Mostafizur Rahman Assistant Professor, Department of Anesthesia, Shaheed Monsur Ali Medical College Hospital, Dhaka, Bangladesh

DOI:

https://doi.org/10.61561/ssbj.v5i2.53

Keywords:

Anisometropic amblyopia, occlusion therapy, visual acuity, refractive errors, pediatric ophthalmology

Abstract

Background: Amblyopia is a common visual disorder in children, often treated with occlusion therapy. This study aimed to assess the visual outcomes following occlusion therapy in children with anisometropic amblyopia, focusing on improvements in best-corrected visual acuity (BCVA) over a six-month period.

Methods: This cross-sectional study was conducted in Shaheed Monsur Ali Medical College Hospital, Dhaka, Bangladesh during the period from January 2015 to August 2015. Participants underwent occlusion therapy, where the better-seeing eye was covered for varying durations based on initial BCVA. Visual acuity was measured using the Snellen chart and converted to logMAR units at baseline, and after 1, 3, and 6 months of therapy. Statistical analysis was performed using Pearson’s correlation test.

Results: The mean BCVA improved significantly from 0.88±0.28 at baseline to 0.55±0.21 after 1 month, 0.42±0.15 after 3 months, and 0.23±0.12 after 6 months (p < 0.001 for all comparisons). Among the participants, 68% had hypermetropia, 22% had astigmatism, and 10% had myopia. The majority of participants (68%) had anisometropic amblyopia in the right eye. The age distribution was 32% aged 5-7 years, 47% aged 8-9 years, and 21% aged 10-11 years, with a mean age of 8.64 years. Gender distribution was 64% male and 36% female.

Conclusion: Occlusion therapy significantly improves visual acuity in children with anisometropic amblyopia, with early and consistent treatment yielding the best results. These findings support the continued use of occlusion therapy as an effective treatment modality, even when initiated later in childhood. Future research should explore long-term outcomes and complementary treatment approaches.

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