Comparison of Conventional Occlusion and Inverse Occlusion in the Treatment of Amblyopia With Eccentric Fixation

To compare conventional and inverse occlusion in the treatment of amblyopia with eccentric fixation.

This prospective randomized interventional study was conducted at a tertiary care center over a period of 1 year. Sixty patients with amblyopia (refractive or strabismic) with eccentric fixation who were older than 12 years were divided into two groups with systematic randomization: conventional occlusion (occlusion of sound eye for 6 hours/day) and inverse occlusion (occlusion of amblyopic eye for 6 hours/day). Patients with a systemic illness or neurological disorder were excluded. Follow-up data for corrected distance visual acuity (CDVA), stereopsis, and fixation pattern were taken at baseline and 1, 3, and 6 months postoperatively.

At the final follow-up visit, there was significant improvement in CDVA in the amblyopic eye in both the conventional occlusion (P = .007) and inverse occlusion (P < .001) groups. The mean ± standard deviation of CDVA improved from 1.32 ± 0.3 and 1.32 ± 0.32 logMAR at baseline to 1.17 ± 0.15 and 1.10 ± 0.27 logMAR in the conventional occlusion and inverse occlusion groups, respectively. Stereoacuity improved significantly in both groups (P = .013 and .016 in the conventional and inverse occlusion groups, respectively). Improvement in fixation function was statistically significant only in the inverse occlusion group I (P = .002).

Both conventional and inverse occlusion therapy are effective in treating amblyopia with eccentric fixation in terms of improvement of visual acuity and stereopsis. However, for improvement in anomalous fixation pattern, inverse occlusion is preferred with no issues of compliance and functional limitation.