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Effect of astigmatism on refraction in children with high hyperopia
Hao Hu1, Jinhui Dai, Minjie Chen
1Department of Ophthalmology, The First People's Hospital of Wenling.
Drug Discoveries & Therapeutics
|November 29, 2016
Summary
Astigmatism extent and type do not significantly impact refractive error regression or visual acuity improvement in children with high hyperopia. These factors appear independent of visual outcome changes over time.
Area of Science:
- Ophthalmology
- Pediatric Ophthalmology
- Refractive Error Research
Background:
- High hyperopia (+5.00D or greater) in children presents unique challenges for visual development.
- Astigmatism, a common refractive error, may influence the natural progression and correction of hyperopia.
- Understanding these influences is crucial for effective management and prediction of visual outcomes.
Purpose of the Study:
- To investigate if the extent and type of astigmatism affect refractive error regression and best-corrected visual acuity (BCVA) in children with high hyperopia.
- To analyze the relationship between different degrees and components of astigmatism and changes in spherical diopters (DS) and BCVA over time.
Main Methods:
- Retrospective analysis of pediatric patients with high hyperopia (≥ +5.00D) from two hospital databases (June 2005 - December 2015).
- Eyes were categorized based on astigmatism extent (≤ -2D, no astigmatism/≥ -0.5D, ≥ -0.75D and ≤ -1.75D) and component (with-the-rule, against-the-rule, oblique).
- Changes in spherical diopters (DS) and best-corrected visual acuity (BCVA) were compared within and among astigmatism groups during follow-up.
Main Results:
- No statistically significant differences in mean DS or BCVA were observed between groups based on astigmatism extent at the final visit.
- Oblique astigmatism was associated with more severe hyperopia initially compared to with-the-rule astigmatism.
- While initial BCVA varied by astigmatism component, changes over the observation period were not significant among groups.
Conclusions:
- The regression of spherical diopters and improvement in best-corrected visual acuity in children with high hyperopia appear to be independent of the extent and component of astigmatism.
- Astigmatism's role in the long-term visual outcome of high hyperopia in children may be less influential than previously thought.
- Further research could explore other potential factors influencing refractive error progression in this population.
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