Comparative efficacy of penalization methods in moderate to mild amblyopia. Atropine penalisation versus occlusion as the primary treatment for amblyopia. Stability of visual acuity improvement following discontinuation of amblyopia treatment in children aged 7 to 12 years.
To compare the efficacy and sensory outcome of pharmacologic and optical penalization in the treatment of moderate to mild amblyopia.
                Randomized clinical trial.
                In an institutional setting, two- to 10-year-old children with strabismic or anisometropic amblyopia (visual acuity in the amblyopic eye at least 20/60) who were cooperative to measure visual acuity using the logarithm of the minimum angle of resolution (logMAR) crowded Glasgow acuity cards were randomized into two groups of therapy (n=35 in each group), 1% atropine, and optical penalization with positive lenses, after stratification by cause of amblyopia. Visual acuity was tested by the logMAR crowded Glasgow acuity cards, after retinoscopic refraction, and deviation angle were measured by the simultaneous prism and cover or Krimsky test. Stereoacuity was determined using the Titmus fly test and Randot preschool or Randot circles stereoacuity test. Change in visual acuity of the amblyopic eye and in interocular difference of visual acuity after six months of amblyopia therapy was the main outcome measure; stereoacuity at six months of therapy was a secondary outcome measure.
                Thirty-one and 32 children completed the outcome examination in the atropine and optical penalization group, respectively. Average improvement in visual acuity of the amblyopic eye was larger in the atropine than in the optical penalization group (3.4 and 1.8 logMAR lines, respectively), as well as average improvement in interocular difference of visual acuity (2.8 and 1.3 logMAR lines, respectively). Better stereoacuity, but nonsignificantly different, was detected in the atropine group.
                Atropine penalization may be considered more effective than optical penalization with positive lenses. Pharmacological penalisation of non-amblyopic eyes is an infrequently used alternative to occlusion for treating amblyopia. The authors compared the efficacy of atropine penalisation and that of occlusion as a primary treatment for amblyopia.
                Thirty six newly diagnosed patients with amblyopia were allocated to two groups for treatment. Eighteen patients in each group were treated either with atropine penalisation (group A) or occlusion therapy (group P).
                There was a statistically significant improvement in visual acuity in both groups treated. In group A improvement of the geometric mean visual acuity of the amblyopic eye was from 6/50 to 6/11 (p < 0.001). In group P improvement of the geometric mean visual acuity was from 6/60 to 6/19 (p < 0.001). In group A non-compliance with treatment was only 6% (2/18). Non-compliance in group P was 45% (8/18) at some stages of the treatment. Neither group produced an incidence of occlusion amblyopia.
                In this study atropine penalisation has been shown to be as effective as occlusion therapy in the treatment of amblyopia. Patient acceptance of atropine penalisation was superior to that for occlusion therapy as was shown by the compliance rate. Atropine treatment was also advantageous in that compliance could be readily checked by inspection. To assess the stability of visual acuity improvement during the first year after cessation of amblyopia treatment other than spectacle wear in children aged 7 to 12 years.
                At the completion of a multicenter randomized trial during which amblyopia treated with patching and atropine improved by at least 2 lines on the electronic Early Treatment of Diabetic Retinopathy Study testing protocol, 80 patients aged 7 to 12 years were followed up while not receiving treatment (other than spectacle wear) for 1 year.
                Ten letters or more (> or =2 lines) worsening of visual acuity (measured using the electronic Early Treatment of Diabetic Retinopathy Study testing protocol) during the year following treatment discontinuation.
                During the year following cessation of treatment, the cumulative probability of worsening visual acuity (> or =2 lines) was 7% (95% confidence interval, 3%-17%); 82% of patients maintained an increase in visual acuity of 10 letters or more compared with their visual acuity before starting treatment.
                Visual acuity improvement occurring during amblyopia treatment is sustained in most children aged 7 to 12 years for at least 1 year after discontinuing treatment other than spectacle wear.
                ClinicalTrials.gov identifier: NCT00094692.
Both conventional occlusion and atropine penalization produce visual acuity improvement in the amblyopic eye. Atropine penalization appears to be as effective as conventional occlusion, although the magnitude of improvement differed among the three trials. Atropine penalization can be used as first line treatment for amblyopia.