Digital Treatment Boosts Visual Acuity in Unilateral Amblyopia

A digital, software-driven therapeutic improved visual acuity in pediatric patients with unilateral amblyopia with anisometropia, strabismus, or both in a phase 3 randomized controlled trial published in Ophthalmology.

“To the best of our knowledge, this is the first successful, adequately powered RCT of a dichoptic therapy for amblyopia,” according to the researchers. “It is also the first successful RCT of a device that leverages a head-mounted display and a broad library of popular video content for amblyopia treatment.”

Patients (n=105, mean age 6.1±1.0 years old) with amblyopia from 21 clinical sites participated in the study. Best-corrected visual acuity (BCVA) was 20/40 to 20/200 in the amblyopic eye (0.54±0.21 logMAR in treatment group 0.50±0.19 logMAR in continued glasses) and at least 20/32 in the fellow eye. Strabismus was less than or equal to 5 prism diopters.

Participants were randomly assigned to treatment and continued glasses (n=51) or solely continued glasses (n=54) for 12 weeks. Examiners were masked. The continued glasses group received placebo.

The treatment group received therapeutic visual stimuli through video content presented through a smartphone and virtual reality headset for 1 hour per day, 6 days per week. Researchers reduced total contrast of images presented to fellow eye to 15% of that for the amblyopic eye and masked images so that patients needed to use both eyes to fully appreciate the video.

After 12 weeks, VA in the amblyopic eye had improved more in the treatment group (1.8 lines 0.18 logMAR; 95% CI 1.4-2.3 lines n=45) compared with in the control group (0.8 lines 0.08 logMAR 95% CI 0.4-1.3 lines n=45 P =.0011). Sixty-two percent (95% CI 47%-76%) of participants in the treatment group and 33% in the continued glasses group (95% CI 20%-49%) had at least 2 lines of VA improvement from baseline in the amblyopic eye (P =.006). The trend held in supportive analyses except for a subgroup of children 5 years of age and younger, which was too small for analysis.

Nearly all parents (34 of 36) of participants in the treatment group who had previously used patches said they were “likely” or “very likely” to choose the therapeutic in place of patching, and 73% were almost certain (9 or 10 on a scale of 0 being very unlikely to 10 being very likely) they would recommend it to someone else.

Total hours of therapeutic use was linked with patient satisfaction (Spearman’s =0.40; P =.006).

No serious adverse events occurred, the researchers reported. Common adverse events included worsening VA (3 in treatment group 4 control individuals), headaches (4 in treatment group, 1 control individual), and new heterotropias (3 in the treatment group, 2 control individuals).

Limitations of the study include unknown durability of the benefit of the therapeutic correction, limited length of the study, and wide confidence intervals.

The researchers said the study’s results should not be generalized beyond the study’s design.

Disclosure: This research was supported by Luminopia, Inc. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Xiao S, Angjeli E, Wu HC, et al. Randomized controlled trial of a dichoptic digital therapeutic for amblyopia. Ophthalmol. Published online September 13, 2021. doi:10.1016/j.ophtha.2021.09.001