Long-term results of treatment of amblyopia in children with impaired fixation mechanism using biofeedback

Purpose: to evaluate the long-term results (1 year) of a new method of treating amblyopia in children with unstable central and eccentric fixation using microperimetric biofeedback, as well as to develop a protocol for patients monitoring after treatment and clear criteria for prescribing repeated courses of treatment using microperimetric biofeedback.

Material and methods. The study included 21 patients (21 eyes) aged from 5 to 15 years (ave 8.28 ± 3.08) who were able to perform training sessions on the MP-3 microperimeter (MP, Nidek, Japan). Treatment was carried out on the MP using visual (flickering checkerboard pattern) and sound (sound signal) biofeedback: 10–15 sessions, 10–12 minutes each. All patients were examined before treatment, immediately and 1, 3, 6 and 12 months after the treatment. Dynamic observation of patients and prescription of repeated courses of treatment were carried out in accordance with the developed protocol.

Results. After 1 course of treatment, a significant increase in best-corrected visual acuity (BCVA) was detected in 90.4 % of patients, as well as an improvement in all fixation parameters: a significant increase in density by 2° and 4°, a decrease in amplitude by ≈ 50 %; a tendency to increase the functional parameters of the retina in the macular area. During follow-up (1 year), 13 patients (1 patient with central fixation and 12 patients with eccentric fixation) underwent additional courses of biofeedback therapy in accordance with the developed protocol. In 4 patients with eccentric fixation, mainly peripheral, despite improvement in fixation parameters, no additional positive dynamics in visual acuity were noted after a repeated course of biofeedback therapy. In 8 patients, after a repeated course of treatment of amblyopia using biofeedback therapy, positive dynamics were noted, namely: an increase in density and a decrease in the amplitude of fixation, and an increase in BCVA.

Conclusion. The effectiveness and safety of a previously developed method of treating amblyopia with impaired fixation mechanism using biofeedback therapy has been demonstrated. A protocol for dynamic monitoring of patients with amblyopia after biofeedback therapy and criteria for prescribing additional courses of training sessions have been developed.

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