Standard Amblyopia Therapy in Adults with Longstanding Amblyopia Improves Visual Acuity and Contrast Sensitivity.

Abstract

Perceptual learning or dichoptic training may result in improved acuity in adult amblyopes. However, for amblyopic children (<18 years), most clinicians recommend standard part-time patching. The purpose of this study was to determine if standard amblyopia therapy results in an enhancement in vision in the amblyopic eye of adults. Fifteen amblyopes (20/30 or worse) were recruited and nine (age (SD) 32.9 (16.31)) with anisometropia or anisometropia and strabismus (ie, combined mechanism amblyopia) completed the study. Previous therapy did not exclude subjects. The subjects received a comprehensive eye exam and wore their best correction for at least four weeks prior to baseline testing. The non-amblyopic eye was patched for 2 hours per day (Amblyopia iNET training for 30 minutes and near/distance activities for 1.5 hours). The subjects had a baseline amblyopia evaluation followed by one visit per week for 12 weeks. At 12 weeks, the treatment was tapered off over one month and the subjects had a final amblyopia evaluation at 24 weeks. Contrast sensitivity was measured at baseline and 12 weeks with the Quick CSF system. The subjects had a significant improvement in visual acuity across the weeks (p < 0.001). At baseline, weeks 12 and 24, the average logMAR acuities (SE) were 0.55 (0.09), 0.41 (0.08), and 0.38 (0.09), respectively. Weeks 4 to 24 were significantly different (p < 0.001) from baseline. The average acuity improvement over the 24 weeks was 1.7 logMAR lines. There was a significant increase in the area under the log contrast sensitivity function (p = 0.002) and its estimated acuity (p = 0.036) from baseline to 12 weeks. Standard amblyopia treatment can result in an improvement in visual acuity and contrast sensitivity in adults with longstanding anisometropic or combined mechanism amblyopia even if they had prior therapy.