Optical Correction and Visual Functions of Adults With Amblyopia

Last updated: June 13, 2024
Sponsor: Centre for Eye and Vision Research
Overall Status: Active - Recruiting

Phase

N/A

Condition

Eye Disease

Eye Disorders/infections

Vision Loss

Treatment

Spectacles

Clinical Study ID

NCT05394987
SPECTRA
  • Ages 18-39
  • All Genders
  • Accepts Healthy Volunteers

Study Summary

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

Inclusion

Inclusion Criteria:

  • 18-39 (inclusive) years of age

  • Anisometropic amblyopia (difference of ≥0.50D spherical equivalent or ≥1.50Dastigmatism between eyes) or mixed mechanism amblyopia (strabismus andanisometropia)

  • 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 VAdifference of 2 logMAR lines or more

  • Difference of 1.00D or more between current refractive correction and studyprescription

  • Good general health

Exclusion

Exclusion Criteria:

  • 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 toaniseikonia)

  • Contraindication to cycloplegic eye drops

  • Currently under amblyopia treatment/therapy

  • Inability to comprehend test instructions and/or provide consent

  • Eccentric fixation

  • >-6.00DS of myopia in either eye with spectacles

  • Bilateral amblyopia

  • Presence of amblyopia that is not due to strabismus and/or anisometropia

  • Presence of (current or previous) psychiatric, visual, or neurological disorders

Study Design

Total Participants: 36
Treatment Group(s): 1
Primary Treatment: Spectacles
Phase:
Study Start date:
June 13, 2022
Estimated Completion Date:
May 31, 2027

Connect with a study center

  • University of Waterloo

    Waterloo, Ontario N2L 3G1
    Canada

    Active - Recruiting

  • Centre for Eye and Vision Research Limited

    Hong Kong, Guangdong 00000
    Hong Kong

    Active - Recruiting

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