Factors influencing occlusion therapy in refractive amblyopia

Abstract

Introduction: Amblyopia is an of important cause of preventable blindness and early detection with timely rehabilitation can prevent blindness in childhood age. It also carries a higher risk of vision loss in fellow eye. The most common method of treatment to recover the monocular function involves patching the good eye in an effort to reinforce the amblyopic eye to improve. In our study we evaluated the factors affecting occlusion therapy in amblyopia patients in terms of age, gender, amount of refractive error and the time period of occlusion as the influential factor in rehabilitation of amblyopia. Methods: In this observational study, all patients between 3 years to 25 years who attended the ophthalmic OPD at Sri Siddhartha Medical College, a tertiary health care centre for ocular evaluation and diagnosed with amblyopia were included in the study. The patients were evaluated for Visual acuity on Snellens visual acuity chart and then subjected to Refractive error evaluation on Unique RK 800 Autorefractometer. Anterior segment was evaluated on Slit lamp and Fundus examination was done on Direct and indirect ophthalmoscope. Post refraction and Post treatment visual acuity was evaluated for the patients on Snellens visual acuity chart. Results: Total of 42 patients were studied out of which 16 were males and 26 were females. All patients were between 3- 35 years of age, with maximum patients 20 (47. 6%) in the age group of 6 to 15 years. 21 patients (50%) were having a baseline visual acuity in the range of 3 meter finger counting to 6/36. The commonest refractive error was astigmatism 23(54.8%) amongst whom compound myopic astigmatism was commonest in 9 patients (21.4%). In our study the post correction visual acuity improvement was 6/24 to 6/6 which was found in maximum patients 31 (73.8%), which further improved in the post occlusion visual acuity in 35 patients (83.3%) from 6/24 to 6/6. Conclusion: In this study we found myopic astigmatism as the commonest refractive error in anisometropic amblyopias. Though we found a female preponderance, the gender association was not found significant in the visual recovery or the treatment response. A good improvement following occlusion treatment as well as refractive adaptation period