AIM: To measure and analysis axial length(AL)/corneal radius of curvature(CRC) ratio and other refractive parameters, provide a medical reference range for refractive development evaluation and earlier visual impairme...AIM: To measure and analysis axial length(AL)/corneal radius of curvature(CRC) ratio and other refractive parameters, provide a medical reference range for refractive development evaluation and earlier visual impairment screening of 3 to 4 y kindergarten students.METHODS: Between April and June 2017, a total of 4350 participants aged 3-to 4-year-old(8700 eyes) from 10 cluster random sampling kindergartens in Shanghai, Pudong District were involved. According to the measurement and analysis of the unaided visual acuity(VA), AL, CRC, AL/CRC ratio, astigmatism and other refractive parameters, the data distribution and reference range were obtained.RESULTS: Uncorrected VA of examined children was 0.23±0.08(logMAR, mean±SD) [95% confidence interval(CI) range ≤0.36];AL was 22.10±0.79 mm(95%CI 20.55-23.65);CRC was 7.86±0.26 mm(95%CI, 7.35-8.37);AL/CRC ratio was 2.81±0.12(95%CI, 2.57-3.05). The median of astigmatism was-0.5 D, a total of 56.3% had astigmatism <-0.50 D, 85.3%<-1.00 D, 6.7%>-1.50 D;71% were astigmatism with the rule. Eye-specific analyses were conducted. Statistical difference of VA was in right and left eyes. There were no significant differences between two eyes of AL, CRC, AL/CRC ratio and astigmatism(P>0.05).CONCLUSION: VA and AL/CRC ratio reference could be used to assess refractive development in children and screening uncorrected refractive errors or amblyopia. Astigmatism needs to be considered in the diagnosis.展开更多
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-section...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 6-11 y 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.展开更多
基金Supported by the National Natural Science Foundation of China(No.81371040)Shanghai Smart Medical Special Research Project(No.2018ZHYL0221)+1 种基金Shanghai Municipal Education Commission-Gaofeng Clinical Medicine Grant Support(No.20181810)the Science and Technology Commission of Shanghai(No.17DZ2260100)
文摘AIM: To measure and analysis axial length(AL)/corneal radius of curvature(CRC) ratio and other refractive parameters, provide a medical reference range for refractive development evaluation and earlier visual impairment screening of 3 to 4 y kindergarten students.METHODS: Between April and June 2017, a total of 4350 participants aged 3-to 4-year-old(8700 eyes) from 10 cluster random sampling kindergartens in Shanghai, Pudong District were involved. According to the measurement and analysis of the unaided visual acuity(VA), AL, CRC, AL/CRC ratio, astigmatism and other refractive parameters, the data distribution and reference range were obtained.RESULTS: Uncorrected VA of examined children was 0.23±0.08(logMAR, mean±SD) [95% confidence interval(CI) range ≤0.36];AL was 22.10±0.79 mm(95%CI 20.55-23.65);CRC was 7.86±0.26 mm(95%CI, 7.35-8.37);AL/CRC ratio was 2.81±0.12(95%CI, 2.57-3.05). The median of astigmatism was-0.5 D, a total of 56.3% had astigmatism <-0.50 D, 85.3%<-1.00 D, 6.7%>-1.50 D;71% were astigmatism with the rule. Eye-specific analyses were conducted. Statistical difference of VA was in right and left eyes. There were no significant differences between two eyes of AL, CRC, AL/CRC ratio and astigmatism(P>0.05).CONCLUSION: VA and AL/CRC ratio reference could be used to assess refractive development in children and screening uncorrected refractive errors or amblyopia. Astigmatism needs to be considered in the diagnosis.
基金Supported by the National Natural Science Foundation of China for Youth(No.81500755)。
文摘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 6-11 y 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.
