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Published on: March 24, 2020
Strabismus and binocular functions in a sample of Swedish children aged 4-15 years
Eva Aring1, Marita Andersson Grönlund, Susann Andersson
1Institute of Clinical Neuroscience, Section of Ophthalmology, Department of Paediatrics, The Sahlgrenska Academy at Göteborg University, Ostra, SE-416 85 Göteborg, Sweden. eva.aring@vgregion.se
Insights
This study examined vision in 143 Swedish children, finding low rates of strabismus (3.5%) and high stereoacuity. Most children had normal ocular alignment and convergence, suggesting good visual function in this pediatric sample.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Vision Science
Background:
- Strabismus and other binocular vision anomalies are common pediatric concerns.
- Understanding the prevalence of these conditions in specific populations is crucial for early detection and intervention.
Purpose of the Study:
- To assess the prevalence of strabismus, heterophoria, and related visual functions in a sample of Swedish children.
- To evaluate parameters including head posture, nystagmus, stereoacuity, ocular motility, near point of convergence (NPC), and accommodative convergence to accommodation ratio (AC/A).
Main Methods:
- A prospective cross-sectional study involving 143 children aged 4-15 years.
- Utilized a comprehensive battery of clinical tests to assess various visual functions.
Main Results:
- Heterotropia (strabismus) was observed in 3.5% of children (4 esotropia, 1 exotropia).
- Heterophoria was present in 26% of children, more common at near than distance.
- Near point of convergence (NPC) was normal in 97%, and 97% had good stereoacuity (60" or better).
- Median AC/A ratios were 5.6/1 PD/D (heterophoria method) and 1.3/1 PD/D (gradient method).
- No anomalous head postures or nystagmus were detected; all children exhibited normal ocular versions.
Conclusions:
- The study provides normative data for key visual parameters in a cohort of Swedish children.
- Findings align with other population-based studies, supporting their use for clinical comparisons.
- The results indicate generally good binocular vision function and alignment in the studied pediatric group.
Purpose:
To investigate strabismus, head posture, nystagmus, stereoacuity, ocular motility, near point of convergence (NPC) and accommodative convergence to accommodation ratio (AC/A) in a sample of Swedish children.
Methods:
A prospective cross-sectional study was carried out on 143 children, 4-15 years of age.
Results:
Heterotropia was found in five children (3.5%), four with esotropia and one with exotropia. One child with esotropia had a slight overaction of both inferior oblique muscles. Heterophoria was found in 37 children (26%) at near and/or distance fixation and it was four times more common at near than at distance. In 29 children, heterophoria was found at one distance only and orthophoria at the other. Orthophoria at both near and distance fixation was noted in 101 children (70.5%). The near point of convergence was < or =6 cm in 97% of the children and 97% had stereoacuity of 60" or better. In the whole group, the median AC/A ratio calculated with the heterophoria method was 5.6/1 prism diopters/diopters (PD/D) and with the gradient method, 1.3/1 PD/D. No anomalous head postures or nystagmus were observed and all children had normal versions.
Conclusion:
In this study, 143 well-defined children were investigated with a battery of accurately described tests, commonly used in clinical practice. These results are in agreement with those of other studies examining one or few variables in larger populations and the authors therefore conclude that their results may be used for comparisons with different patient groups.
