Review of preschool vision screening referrals in South Auckland, New Zealand

Abstract

Background: Limited data are available on the causes of visual impairment in preschool children in New Zealand. We aimed to review demographic and visual parameters in children referred to the Ophthalmology Department, Manukau Super Clinic from vision screening programmes in South Auckland. Methods: Retrospective medical record review of 131 children, aged 3-5, referred from community-based vision screening programmes to the Ophthalmology Department for further assessment. Medical records were reviewed to determine: reason for referral, findings from ophthalmic assessments, treatment received and visual acuity at final visit. The main outcome measures were cause of visual impairment in children referred from preschool vision screening and visual acuity at final follow-up visit. Results: Thirty-eight children (29.0%) were discharged after their initial assessment as false positive referrals. Approximately half (45.5%) of children were prescribed glasses for the correction of refractive error, amblyopia or strabismus. Twenty-nine (22.1%) children were diagnosed with amblyopia with an average follow-up period of 17.5 ± 2.7 months. In general, compliance with amblyopia therapy was poor with 48.3% non-compliant to their prescribed treatment regimen. Despite this, visual outcomes were good with an average final visual acuity in the amblyopic eye of 0.294 ± 0.231 logMAR (Snellen 6/12). Conclusions: The Positive Predictive Value for the Counties-Manukau preschool vision screening programme was 47.4%, suggesting the visual acuity measurements alone produce a significant number of false positive results. In children diagnosed with amblyopia early detection and intervention showed significant improvement in vision in the amblyopic eye, with many children also showing improved binocular function.