Analysis Of The Correlation Between Refractive State And Refractive Parameters In Children Aged 3?12 Years

Objective:To understand the developmental characteristics of refractive state and ocular refractive parameters in 3~12 year old children,and to analyze the relationship between refractive parameters and diopter in different age groups and different refractive states.To provide basis for further research on refractive errors and myopia prevention and control in preschool and school-age children.Methods:1200 eyes of 3~12 year old preschool and school-age children were randomly selected from June 2017 to June 2018 in our ophthalmology clinic.There were 300 males and 300 females with an average age of 7.5±2.87 years.Through 1%atropine ophthalmic gel dilation,3 times a day for 3 days,the static diopter(D),axis length(AL),corneal refractive power(horizontal corneal refractive power K1,vertical corneal refractive power K2),anterior chamber depth(ACD)was obtained by optometry and intraocular len Master(IOL-Master),and calculate corneal curvature radius(CR),axis length/corneal curvature radius ratio(AL/CR)and lens refractive power(LP).They were divided into 3~6 year old,7~9year old and 10~12 year old groups by age.According to SER,divided into hyperopia(>0.50D),emmetropia(0.50D~-0.50D),mild myopia(-0.50D~-3.00D),moderate myopia(-3.25D~-6.00D)and high myopia(<-6.00D).All the data were analyzed by SPSS22.0 statistical software.The counting data were expressed as rates.The incidence and 95%confidence interval of different types of refraction were calculated.The refractive state of different age groups and sex was tested by?2 test.The measurement data were described by~_x±s.The refractive parameters of boys and girls were compared by independent sample T-test.The refractive parameters of different age groups and different refractive groups were compared by one-way ANOVA analysis.Linear regression analysis was used to analyze the correlation between equivalent spherularity and refractive parameters in different age groups and different refractive groups.Comparison of linear regression lines between different age groups and different refractive groups using covariance analysis and F test Analysis.Inspection level P<0.05.Results:(1)emmetropia 212 eyes(17.67%),hyperopia 581 eyes(48.42%),myopia 407 eyes(33.92%).There was a significant difference in refractive state among different age groups(P<0.000).The incidence of myopia was the highest in the 10~12 year old group(251/360,69.72%),the next in the7~9 year old group(124/360,34.44%),and the lowest in the 3~6 year old group(34/480,7.08%).The incidence of hyperopia was the highest in the3~6 year old group(350/480,72.91%),the next in the 7~9 year old group(175/360,48.61%)and the lowest in the 10~12 year old group(54/360,15.00%).While the incidence of myopia in the male group was higher than that in the female group(37.6%VS 30.83%,P=0.021).(2)SER(2.01 D,0.54 D,1.63 D,P<0.000)and LP(27.40 D,23.48 D,19.06 D,P<0.000)gradually decreased with age.AL(22.13 mm,23.13 mm,24.23 mm),ACD(3.23 mm,3.44 mm,3.63 mm,P<0.000)and AL/CR(2.85,2.98,3.13,P<0.000)increased with age.CR(7.78 mm,7.77 mm,7.75 mm,P=0.66)was stable.AL,ACD,CR and AL/CR of boys in different age groups were higher than girls,and LP was lower than girls(P<0.05).(3)In different age groups,AL is highly correlated with SER(R=0.80,R=0.85,R=0.81;P=0.000),ACD is moderate correlated with SER(R=0.39,R=0.57,R=0.56;P=0.000).There was no significant correlation between CR and SER.AL/CR is highly correlated with SER(R=0.70,R=0.90,R=0.92;P=0.000).LP is strongly correlated with SER(R=89,R=0.92,R=0.91;P=0.000).(4)In different diopter groups,AL(22.02mm,22.93mm,24.30mm,25.02mm,26.23mm,P<0.000),ACD(3.23mm,3.37mm,3.67mm,3.75mm,3.83mm,P<0.000),AL/CR(2.83,2.95,3.12,3.26,3.45,P<0.000)increased with SER(3.11D,0.05D,-1.63D,-4.09D,-8.73D,P<0.000),LP(28.09 D,24.17D,19.27D,15.54D,10.48D,P<0.000)decreases with SER,CR(7.79mm,7.79mm,7.78mm,7.68mm,7.60mm,P=0.001)is stable.(5)In hyperopia group,AL,ACD,CR,AL/CR and LP correlated with SER(R=0.66,R=0.40,R=0.29,R=0.62,R=0.84;P<0.000);In emmetropia group,no significant correlation between the refractive parameters and SER.In mild myopia group,AL,ACD,CR,AL/CR and LP correlated with SER(R=0.55,R=0.20,R=0.18,R=0.51,R=0.60;P<0.000);In moderate myopia group,AL,AL/CR and LP correlated with SER(R=0.30,R=0.44,R=0.48;P<0.000);In highmyopia group,AL,AL/CR and LP correlated with SER(R=0.68,R=0.76,R=0.78;P<0.000);In different myopia groups,the difference of linear regression line between AL/CR and SER is statistically significant(P<0.001).(6)Adjusted for age and gender,AL is highly negative correlated with SER(R2=0.725,?=-1.94),ACD is moderate negative correlated with SER(R~2=0.361,?=-6.601),AL/CR is highly negative correlated with SER(R~2=0.71,?=-13.12),LP is strongly negative correlated with SER(R~2=0.843,?=0.516).For the SER variance,AL explained 72.5%,ACD explained 36.1%and LP explained 84.3%after adjusting for age and gender.Conclusion:7~9 years old can be regarded as the main phase from emmetropization to myopization of school-age children.AL and LP are the main factors that affect the development of refractive and myopia.AL/CR can be used as a high risk indicator to measure whether emmetropization into myopia and can be used to classify different grades of myopia.