About this trial
Amblyopia is a developmental anomaly resulting from abnormal visual experiences in early life. Amblyopia causes reduced visual acuity in the absence of a pathology. Adult sensory systems are believed to be structurally invariant beyond early, critical periods of development. However, recent evidence suggest that visual functions in adults with amblyopia can be improved with optical correction alone. This study aims to investigate whether improvements in best corrected visual acuity and other visual functions can result following appropriate optical correction in adults with amblyopia. Functional measures relating to vision, binocular vision, and eye movements will be used to assess the efficacy of refractive correction for improving vision. This study will help us better understand the improvements in visual functions following optical correction, as well as the mechanisms underlying neuroplasticity in adults with amblyopia.
Eligibility criteria
Qualifiers
18-39 (inclusive) years of age
Anisometropic amblyopia (difference of ≥0.50D spherical equivalent or ≥1.50D astigmatism between eyes) or mixed mechanism amblyopia (strabismus and anisometropia)
Best corrected visual acuity (BCVA) in the amblyopic eye of 0.3 logMAR to 1.0 logMAR (inclusive)
BCVA in the non-amblyopic eye of 0.1 logMAR or better, and an interocular VA difference of 2 logMAR lines or more
Disqualifiers
Other pathological ocular anomalies known to cause reduced visual acuity
Presbyopia (based on amplitude of accommodation)
Inability to tolerate prescribed refractive correction in spectacles (e.g., due to aniseikonia)
Contraindication to cycloplegic eye drops
Trial design
Treatments tested in this trial
- Spectacles
Treatment groups
Sponsors and collaborators
Centre for Eye and Vision Research
Lead sponsor
The Hong Kong Polytechnic University
Collaborator
University of Waterloo
Collaborator