Clinical Trials

Inclusion Criteria:

• Age 3 to < 13 years at the time of randomization.
• Amblyopia associated with anisometropia, strabismus, or both.
• Criteria for strabismic amblyopia: At least one of the following must be met: 
  • Presence of a heterotropia on examination at distance or near fixation (with or without optical correction);
  • Documented history of strabismus which is no longer present (which in the judgment of the investigator could have caused amblyopia).
• Criteria for anisometropia: At least one of the following criteria must be met: 
  • ≥ 1.00 D difference between eyes in spherical equivalent (SE); 
  • ≥ 1.50 D difference in astigmatism between corresponding meridians in the two eyes.
• Criteria for combined-mechanism amblyopia: Both of the following criteria must be met: 
  • Criteria for strabismus are met (see above);
  • ≥ 1.00 D difference between eyes in spherical equivalent OR ≥ 1.50 D difference in astigmatism between corresponding meridians in the two eyes. 
• No previous treatment for amblyopia, including no more than 24 hours of spectacle wear.
• Investigator planning to initiate spectacle correction of refractive error meeting the following criteria based on a cycloplegic refraction that has been performed within 30 days: 
  • Full correction of spherical and cylindrical anisometropia;
  • Full correction of astigmatism with the same axis found by the cycloplegic refraction;
  • Allow symmetric reduction of sphere up to 1.50, prescribing such that the most hyperopic meridian is not rendered myopic, in the non-amblyopic eye at baseline;
  • Allow symmetric addition of only -0.25 sphere for participants with plano sphere, spherical myopia, simple or compound myopic astigmatism in the non-amblyopic eye at baseline.
• At enrollment, single VA measured in each eye assessed in trial frames with the spectacle correction the investigator plans to prescribe, using the investigator’s routine method as follows:
  • VA in the amblyopic eye 20/40 to 20/200 inclusive;
  • Age-normal VA in the fellow eye:40,41;
  • 3 years: 0.4 logMAR (20/50) or better; 
  • 4 years: 0.3 logMAR (20/40) or better;
  • 5-6 years: 0.2 logMAR (20/32) or better;
  • 7-12 years: 0.12 logMAR (78 letters) or better; 
  • Interocular difference ≥ 3 logMAR lines (0.3 logMAR) or ≥ 15 letters;
  • When participants return for the Spectacle Baseline / Randomization Visit with their new spectacles, they will need to meet the same criteria as above using the ATS HOTV or E-ETDRS protocol after wearing the new spectacles for at least 10 minutes (based upon the mean of a test and retest of VA in those new spectacles).
• Investigator is willing to prescribe spectacle wear followed sequentially by patching or simultaneous spectacles and patching treatment per protocol.
• Parent and participant willing to forego option of contact lens wear for the duration of the study. 
• Parent understands the protocol and is willing to accept randomization. 
• Parent has phone (or access to phone) and is willing to be contacted by Jaeb Center staff or other study staff. 
• Relocation outside of area of an active PEDIG site for this study within the next 56 weeks is not anticipated.

Exclusion Criteria:

• Previous spectacle wear.
• Previous treatment for amblyopia.