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Refraction in Preschool Children in Kazanlak, Bulgaria
Kiril Slaveykov1, Kalina Trifonova1
1Trakia University, Stara Zagora, Bulgaria.
Insights
Refractive errors like hypermetropia and myopia are common in preschool children. Early ophthalmologist checkups for children under seven are recommended to address these vision issues.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Public Health
Background:
- Eye refractive state changes with axial length, corneal, and lens flattening.
- Infants are typically hyperopic, shifting towards myopia by age 16.
- Understanding refractive error prevalence in young children is crucial for early intervention.
Purpose of the Study:
- To determine the prevalence of refractive errors in preschool children aged 3-6 in Kazanlak, Bulgaria.
- To identify common refractive conditions such as myopia, hyperopia, and astigmatism in this age group.
- To assess the need for early vision screening in preschool populations.
Main Methods:
- A cross-sectional study involving 596 preschool children in Kazanlak, Bulgaria.
- Non-mydriatic refraction screening using a PlusOptix S12c mobile camera.
- Defined myopia (SE ≤ -0.50 D), hyperopia (SE ≥ +2.00 D), and astigmatism (cylindrical diopters ≤ -1.00 D).
Main Results:
- 526 out of 596 children (88.2%) had ametropia or astigmatism.
- Hypermetropia was the most common refractive error (470 children), followed by myopia (46 children).
- Astigmatism was found in 50 children; strabismus, amblyopia, and anisometropia were also noted.
Conclusions:
- The prevalence of refractive errors in Kazanlak preschool children is comparable to other studies.
- Most children presented with emmetropia or mild hyperopia.
- A significant number of children had not seen an ophthalmologist, highlighting the need for mandatory vision checkups before age seven.
Introduction:
The refractive state of the eye changes as the eye's axial length increases and the cornea and lens flatten. In general, eyes are hyperopic at birth, become slightly more hyperopic until the age of 7, which at this point we see a myopic shift toward plano until the eyes reach their adult dimensions, usually by about the age 16.
Aim:
To determine the prevalence of refractive error in preschool children aged 3 - 6 in the city of Kazanlak, Bulgaria.
Materials And Methods:
A cross-sectional study was conducted in a kindergarten based school within the city of Kazanlak, Bul-garia. Out of 15 kindergarten schools, 10 chose to participate in the study. The children underwent non-mydriatic refraction screening using a Plus-Optix S12с mobile camera. Myopia, hyperopia and astigmatism were defined as being a spherical equivalent (SE) ≤ -0.50 D, SE ≥ +2.00 D and cylindrical diopters ≤ -1.00 D.
Results:
A total of 596 children were screened. Out of these 596 children; 526 were with ametropia (470 hypermetropia, 46 myopia) and 50 had astigmatism. Strabismus was found in 12 children, with a further 8 children suffering from amblyopia and finally 8 children were also found to be diagnosed with anisometropia. In 8 cases there were no results due to opacities or due to the small size of the pupil.
Conclusion:
The prevalence of refractive error in preschool children is similar to that found in other research in the field. While most cases fall into the category of emmetropia or mild hypermetropia, most of the children had never been to an ophthalmologist. A manda-tory checkup should be issued for all children below the age of seven.
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