Successful persistent strabismic amblyopia treatment using active therapy as an adjuvant to occlusion

Abstract

Purpose A novel protocol to improve long-term results in the treatment of amblyopia was proposed. The protocol combines active home-based therapy through perceptual learning activities (Gabor patch, dichoptic stimulation, and random dot stereograms) with conventional visual therapy in the clinic as an adjunct to patching occlusion in subjects with patch-resistant amblyopia Methods Between 2018 and 2022, a group of patients received treatment for persistent strabismic and combined-mechanism amblyopia according to the novel treatment protocol, consisting of in-clinic orthoptics/visual therapy combined with the use of gamified PL software at home, as an adjunct to occlusion treatment. Results A retrospective analysis of treatment outcomes was subsequently carried out for 53 patients aged 7.75±5.88. Eccentric fixation was present in 17 of the 53 subjects. The distribution of patients presenting with combined-mechanism and strabismic amblyopia was 37 and 16, respectively. Eighteen patients (34 %) demonstrated measurable stereoacuity prior to treatment. Following treatment using the combined treatment protocol, forty-six (87 %) participants achieved a of logMAR 0.1 or better, mean BCVA was significantly improved, from logMAR 0.30±0.23 to logMAR 0.07±0.12 (p < 0.01). Eleven subjects (65 %) of seventeen participants with eccentric fixation achieved central fixation. In addition, stereoacuity was measurable in 43 patients (81 %). Mean stereoacuity improved, from 1200.00±258.69 arc seconds to 539.62±518.69 arc seconds (p < 0.01). These results remained stable six months after completion of the therapy. Conclusion The outcomes of the proposed novel treatment protocol were reduced angle of deviation, and improved BCVA and stereoacuity in patients with persistent strabismic and combined-mechanism amblyopia.