Saturday, November 7, 2026

2:15 PM - 2:30 PM

Ballroom 1 and 2

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Overview

Chantelle Li On Wing

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Details

Purpose: This study aims to report longitudinal changes in heterophoria and the impact of refractive error on ocular alignment. Methods: The Sydney Myopia Study (SMS) is a population-based random cluster sample of school children in two age cohorts. At baseline assessment, the younger cohort was aged 6 years (n=1725) and the older cohort was aged 12 years (n=2340). Follow-up assessment of both cohorts was conducted 5-6 years later. A comprehensive eye examination included visual acuity, orthoptic assessment and cycloplegic autorefraction (cyclopentolate 1%). Results: At baseline, the most common ocular alignment at distance fixation was orthophoria in the younger (83.3%) and older cohort (88.7%). At near fixation exophoria was more common in the younger (57.1%) and older cohort (51.2%). Most children in the younger (77.6%) and older cohort (85.1%) without significant refractive errors at baseline, and who were exophoric or esophoric at distance fixation, became orthophoric by follow-up. Similarly, 100.0% of the younger cohort and 83.3% of the older cohort with myopia and exophoria at baseline became orthophoric by follow-up. However, in children with a hyperopic refraction, the outcomes were more variable. In the younger cohort, only 66.7% of those with an esophoria became orthophoric and two of three children who had exophoria became an exotropia by follow-up. In the older cohort, only 50% of children with an exophoria or esophoria at distance became orthophoric by follow-up. Conclusion: Having no significant refractive error increases the likelihood of orthophorisation regardless of baseline ocular alignment.

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Speaker