ABSTRACT
Aim: To compare the efficacy of part-time versus full-time occlusion for treatment of amblyopia in children aged 7-12 years. Materials and Methods: Prospective interventional case series. One hundred children between 7-12 years of age with anisometropic (57), strabismic (25) and mixed (18) unilateral amblyopia were randomized (simple randomization) into four groups (25 each) to receive two hours, four hours, six hours or full-time occlusion therapy. Children were regularly followed up at six-weekly intervals for a minimum of three visits. Statistical Analysis: Intragroup visual improvement was analyzed using paired t-test while intergroup comparisons were done using ANOVA and unpaired t-test. Results: All four groups showed significant visual improvement after 18 weeks of occlusion therapy ( P < 0.001). Seventy-three (73%) of the total 100 eyes responded to amblyopia therapy with 11 eyes (44%), 17 eyes (68%), 22 eyes (88%) and 23 eyes (92%) being amblyopia responders in the four groups respectively, with the least number of responders in the two hours group. In mild to moderate amblyopia (vision 20/30 to 20/80), there was no significant difference in visual outcome among the four groups ( P =0.083). However, in severe amblyopia (vision 20/100 or worse), six hours ( P =0.048) and full-time occlusion ( P =0.027) treatment were significantly more effective than two hours occlusion. Conclusion: All grades of part-time occlusion are comparable to full-time occlusion in effectiveness of treatment for mild to moderate amblyopia in children between 7-12 years of age unlike in severe amblyopia, where six hours and full-time occlusion were more effective than two hours occlusion therapy.
ABSTRACT
PURPOSE: To analyse results of full time occlusion therapy for amblyopia in children older than 6 years. MATERIALS AND METHODS: This was a retrospective consecutive case series analysis of children treated for amblyopia at a tertiary care center. All children received full time occlusion (FTO) for the dominant eye. RESULTS: Eighty-eight children older than 6 years at the time of initiation of therapy were included. Age at initiation of therapy ranged from 6 to 20 years (9.45 +/- 3.11 years). Forty-two children (47.7%) had strabismic amblyopia, 37 (42.0%) had anisometropic amblyopia and 9 (10.2%) had a combination of strabismic and anisometropic amblyopia. Eighty out of 88 eyes (90.0%) had improvement in visual acuity following FTO. Visual acuity (VA) improved from 0.82 +/- 0.34 at presentation to 0.42 +/- 0.34 (P < 0.001) after FTO. In children with strabismic amblyopia, VA improved from 0.81 +/- 0.42 to 0.42 +/- 0.39 (P <0.001). In children with anisometropic amblyopia, visual acuity of the amblyopic eye improved fron 0.82 +/- 0.24 to 0.36 +/- 0.29 (P< 0.001) following FTO. Out of 13 children older than 12 years, only 6 children (46.1%) had improvement in VA. Mean follow-up after complete stoppage of occlusion was 8.37 +/- 1.78 months. CONCLUSION: Occlusion therapy yields favorable results in strabismic and/or anisometropic amblyopia, even when initiated for the first time after 6 years of age. After 12 years of age, some children may still respond to occlusion of the dominant eye.