Proportion and characteristic of emmetropia in schoolchildren aged 6-11y: the Shenzhen elementary school eye study
AIM: To investigate the proportion and characteristic of emmetropia in schoolchildren aged 6-11, especially estimate the normal value of ocular biometric parameters of emmetropia. METHODS: A population-based cross-sectional study was conducted on children aged 6-11y in Shenzhen. Totally, 2386 schoo...
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| Format: | Article |
| Language: | English |
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Press of International Journal of Ophthalmology (IJO PRESS)
2020-12-01
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| Series: | International Journal of Ophthalmology |
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| Online Access: | http://ies.ijo.cn/en_publish/2020/12/20201221.pdf |
| _version_ | 1818436643591290880 |
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| author | Xian-Ming Jiang Ying-Ying Lu Xiao Han Qian Tan Jun-Shu Wu |
| author_facet | Xian-Ming Jiang Ying-Ying Lu Xiao Han Qian Tan Jun-Shu Wu |
| author_sort | Xian-Ming Jiang |
| collection | DOAJ |
| description | AIM: To investigate the proportion and characteristic of emmetropia in schoolchildren aged 6-11, especially estimate the normal value of ocular biometric parameters of emmetropia.
METHODS: A population-based cross-sectional study was conducted on children aged 6-11y in Shenzhen. Totally, 2386 schoolchildren from two primary schools were involved. The axial length (AL) and the corneal radius of curvature (CRC) were measured by partial coherence laser interferometry. Noncycloplegic refraction and refractive astigmatism (RA) was measured using autorefraction. The axial length-to-corneal radius of curvature ratio (AL/CRC), corneal astigmatism (CA) and spherical equivalent refraction (SER) were calculated.
RESULTS: The proportion of emmetropia in elementary school students was 41.30%. This percentage decreased gradually from 6 to 11 years of age and decreased rapidly after 9 years of age. The mean and 95%CI of each parameter were provided for boys and girls aged 6 to 11 years of age with emmetropia according to each age group. The change trend of parameters of boys and girls are similar. After 7 years of age, the AL of non-emmetropia started to increase faster than that of emmetropia. The change trend of AL/CRC was the same as that of AL. The other parameters tend to be stable after 7 years of age.
CONCLUSION: The age of 7-9 is an important period for the changes of refractive state and ocular biometric parameters of primary school students, and it is a special focus period for children myopia prevention. The normal value and variation of ocular biometric parameters of emmetropia can provide the basis for the clinical judgment of whether or not children’s ocular biometric parameters obtained by single measurement and changes obtained by multiple measurements are abnormal. |
| first_indexed | 2024-12-14T17:12:02Z |
| format | Article |
| id | doaj.art-930e087540044844ac4324062f7bc3b6 |
| institution | Directory Open Access Journal |
| issn | 2222-3959 2227-4898 |
| language | English |
| last_indexed | 2024-12-14T17:12:02Z |
| publishDate | 2020-12-01 |
| publisher | Press of International Journal of Ophthalmology (IJO PRESS) |
| record_format | Article |
| series | International Journal of Ophthalmology |
| spelling | doaj.art-930e087540044844ac4324062f7bc3b62022-12-21T22:53:32ZengPress of International Journal of Ophthalmology (IJO PRESS)International Journal of Ophthalmology2222-39592227-48982020-12-0113121983198910.18240/ijo.2020.12.21Proportion and characteristic of emmetropia in schoolchildren aged 6-11y: the Shenzhen elementary school eye studyXian-Ming Jiang0Ying-Ying Lu1Xiao Han2Qian Tan3Jun-Shu Wu4Department of Ophthalmology, the Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, Guangdong Province, ChinaScientific Research Center, the Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, Guangdong Province, ChinaDepartment of Ophthalmology, the Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, Guangdong Province, ChinaDepartment of Ophthalmology, the Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, Guangdong Province, ChinaState Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, ChinaAIM: To investigate the proportion and characteristic of emmetropia in schoolchildren aged 6-11, especially estimate the normal value of ocular biometric parameters of emmetropia. METHODS: A population-based cross-sectional study was conducted on children aged 6-11y in Shenzhen. Totally, 2386 schoolchildren from two primary schools were involved. The axial length (AL) and the corneal radius of curvature (CRC) were measured by partial coherence laser interferometry. Noncycloplegic refraction and refractive astigmatism (RA) was measured using autorefraction. The axial length-to-corneal radius of curvature ratio (AL/CRC), corneal astigmatism (CA) and spherical equivalent refraction (SER) were calculated. RESULTS: The proportion of emmetropia in elementary school students was 41.30%. This percentage decreased gradually from 6 to 11 years of age and decreased rapidly after 9 years of age. The mean and 95%CI of each parameter were provided for boys and girls aged 6 to 11 years of age with emmetropia according to each age group. The change trend of parameters of boys and girls are similar. After 7 years of age, the AL of non-emmetropia started to increase faster than that of emmetropia. The change trend of AL/CRC was the same as that of AL. The other parameters tend to be stable after 7 years of age. CONCLUSION: The age of 7-9 is an important period for the changes of refractive state and ocular biometric parameters of primary school students, and it is a special focus period for children myopia prevention. The normal value and variation of ocular biometric parameters of emmetropia can provide the basis for the clinical judgment of whether or not children’s ocular biometric parameters obtained by single measurement and changes obtained by multiple measurements are abnormal.http://ies.ijo.cn/en_publish/2020/12/20201221.pdfaxial lengthcorneal radius of curvaturemyopiaemmetropiachildren |
| spellingShingle | Xian-Ming Jiang Ying-Ying Lu Xiao Han Qian Tan Jun-Shu Wu Proportion and characteristic of emmetropia in schoolchildren aged 6-11y: the Shenzhen elementary school eye study International Journal of Ophthalmology axial length corneal radius of curvature myopia emmetropia children |
| title | Proportion and characteristic of emmetropia in schoolchildren aged 6-11y: the Shenzhen elementary school eye study |
| title_full | Proportion and characteristic of emmetropia in schoolchildren aged 6-11y: the Shenzhen elementary school eye study |
| title_fullStr | Proportion and characteristic of emmetropia in schoolchildren aged 6-11y: the Shenzhen elementary school eye study |
| title_full_unstemmed | Proportion and characteristic of emmetropia in schoolchildren aged 6-11y: the Shenzhen elementary school eye study |
| title_short | Proportion and characteristic of emmetropia in schoolchildren aged 6-11y: the Shenzhen elementary school eye study |
| title_sort | proportion and characteristic of emmetropia in schoolchildren aged 6 11y the shenzhen elementary school eye study |
| topic | axial length corneal radius of curvature myopia emmetropia children |
| url | http://ies.ijo.cn/en_publish/2020/12/20201221.pdf |
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