A Randomized Trial of Increasing Patching for Amblyopia

ObjectiveAfter treatment with refractive correction and patching, some patients have residual amblyopia resulting from strabismus or anisometropia. We conducted a clinical trial to evaluate the effectiveness of increasing prescribed daily patching from 2 to 6 hours in children with stable residual amblyopia.DesignProspective, randomized, multicenter clinical trial.ParticipantsA total of 169 children aged 3 to <8 years (mean, 5.9 years) with stable residual amblyopia (20/32–20/160) after 2 hours of daily patching for at least 12 weeks.InterventionRandom assignment to continue 2 hours of daily patching or increase patching time to an average of 6 hours/day.Main Outcome MeasuresBest-corrected visual acuity (VA) in the amblyopic eye after 10 weeks.ResultsBaseline VA was 0.44 logarithm of the minimum angle of resolution (logMAR) (20/50−2). Ten weeks after randomization, amblyopic eye VA had improved an average of 1.2 lines in the 6-hour group and 0.5 line in the 2-hour group (difference in mean VA adjusted for acuity at randomization = 0.6 line; 95% confidence interval, 0.3–1.0; P = 0.002). Improvement of 2 or more lines occurred in 40% of participants patched for 6 hours versus 18% of those who continued to patch for 2 hours (P = 0.003).ConclusionsWhen amblyopic eye VA stops improving with 2 hours of daily patching, increasing the daily patching dosage to 6 hours results in more improvement in VA after 10 weeks compared with continuing 2 hours daily.Financial Disclosure(s)The author(s) have no proprietary or commercial interest in any materials discussed in this article.