Clinical Trial: Observational Study of Optical Correction for Strabismic Amblyopia in Children 3 to <7 Years Old

Study Status: Completed
Recruit Status: Completed
Study Type: Observational

Official Title: An Observational Study of Optical Correction for Strabismic Amblyopia in Children 3 to <7 Years Old

Brief Summary: This study will evaluate the effectiveness of refractive correction alone for the treatment of previously untreated strabismic or combined-mechanism amblyopia in children 3 to <7 years old with visual acuity of 20/40 to 20/400

Detailed Summary:

This study will evaluate the effectiveness of refractive correction alone for the treatment of previously untreated strabismic or combined-mechanism amblyopia in children 3 to <7 years old with visual acuity of 20/40 to 20/400.

A recently completed PEDIG study (ATS5) found that in 3 to < 7-year-old children with previously untreated anisometropic amblyopia, refractive correction alone improved visual acuity by 2 or more lines in 77% of the patients and amblyopia resolved in at least one third of the patients. These results supported previous observations from retrospective and pilot studies as well as Stewart et al's prospective report on 18 children with anisometropic amblyopia whose visual acuity improved after treatment with spectacle correction only.

Improvement in amblyopic eye visual acuity from treatment with optimum refractive correction in cases of anisometropic amblyopia is plausible because the refractive correction treats the underlying amblyogenic condition (i.e., uncorrected unequal refractive error) by providing retinal images of more similar clarity, size, and contrast. Elimination of the dissimilar retinal images, which may act as barriers to normal visual input, allows the amblyopic eye to receive appropriate visual stimulation. In contrast, visual acuity improvement with refractive correction alone in cases of amblyopia associated with strabismus is not expected to occur when the refractive correction does not completely eliminate the strabismus and restore fusion. In such cases, the underlying amblyogenic factor of a manifest ocular deviation remains; consequently, active cortical inhibition is presumably still present. Nonetheless, Stewart and colleagues recently reported finding gains in amblyopic eye visual acuity of children with strabismic and combined-mechanism amblyopia after a period of tr
Sponsor: Jaeb Center for Health Research

Current Primary Outcome: Mean Amblyopic Eye Visual Acuity Improvement With Spectacles [ Time Frame: Enrollment to 18 Weeks ]

Acuity is measured in each eye using the Amblyopia Treatment Study (ATS) visual acuity testing protocol at baseline and at 18wks resulting in a Snellen acuity score that can range from 20/16 to 20/800. The score is converted to logMAR (log of min angle of resolution) for statistical analysis, and a difference between the scores is calculated. A positive difference indicates acuity was better at 18wks than at baseline; a negative difference indicates acuity was worse at 18wks than at baseline.


Original Primary Outcome: Visual acuity [ Time Frame: 18 weeks ]

Current Secondary Outcome:

Original Secondary Outcome:

Information By: Jaeb Center for Health Research

Dates:
Date Received: April 28, 2008
Date Started: May 2008
Date Completion:
Last Updated: July 7, 2016
Last Verified: July 2016