Long-Term Visual Outcome Following Cessation of Occlusion Therapy in Unilateral Amblyopia

ABSTRACT

PURPOSE: To evaluate a long-term visual outcome following cessation of occlusion therapy in unilateral amblyopia. METHODS: A total of 70 patients who successfully finished occlusion therapy (including maintenance therapy) for unilateral amblyopia and were followed up for at least 1 year after cessation of occlusion were retrospectively reviewed. Even after the success of occlusion therapy, maintenance therapy or regular examinations were performed until the visual development of the normal fellow eye (NE) was completed. The recurrence of amblyopia was defined as a 2 or more logarithm of the minimum angle of resolution (LogMAR) levels of visual acuity (VA) reduction of the amblyopic eye (AE), as compared to the NE, at the last evaluation. RESULTS: Amblyopia was associated with strabismus in 19 patients, anisometropia in 33 patients, and both in 39 patients. The mean age at the cessation of occlusion and at the last evaluation was 7.7 +/- 1.9 years and 11.4 +/- 2.9 years, respectively. The mean VA of the AE was 0.01 +/- 0.03 and mean stereopsis was 101.7 +/- 87.5 seconds of arc at the cessation of occlusion, and both improved at the last evaluation. However, the improvement of mean VA of the AE was not statistically significant (p = 0.21). The mean duration of maintenance therapy was 25.6 +/- 21.0 months, and was 3 times longer than the duration required to achieve success in the treatment of amblyopia. At the last evaluation, the recurrence of amblyopia was not found, while 3 patients (4.3%) lost 1 LogMAR level of VA in the AE, as compared to the NE. CONCLUSIONS: Visual outcome following successful cessation of occlusion therapy for unilateral amblyopia was favorable without recurrence of amblyopia.