Research On Refractive Elements Of The Normal And Myopic Children Aged From 7 To 12 Years Old And Establishment Of Refractive Development Files

Objective: To understand the factors of the refractive elements and the relationship between diopter and them among the normal and myopic children aged from 7 to 12 years old.To establish the refractive development files for the school-age children in order to understand the basic pathogenesis of myopia and prevent and control the children's myopia.Methods:107 normal and myopic children(214 eyes),aged from 7to 12 years old,were randomly selected from outpatients who went to our hospital ophthalmology clinic from June 2013 to June 2014.There are 52 boys and 55 girls in our reserach teams.There are 35 cases(70 eyes)in the normal vision group,72 cases(144eyes)in the myopia group.According to the different dioptre,the myopia group will be divided into low myopia group(45 cases),moderate myopia group(20 cases)and high myopia group(7 cases).All the tested children were measured their naked eye sight,static dioptre,the ocular axial length(AL),anterior chamber depth(ACD),corneal refractive power meter(horizontal corneal refractive power K1,vertical corneal refractive power K2 and average corneal refractive power Kv),the eye lens thickness(L)and glass body cavity depth(V).At the same time the refractive development files of all the tested children were established.SPSS22.0 statistical software analysis should be used in all data,and categorical data using mean±standard deviation(x±s)was described.The refractive factor variance between the different eyes were analysised by paired samples t test.Refractive factor differences between different genders were analysised by independent sample t test.The refractive factor variance between the different ages were analysised by analysis of variance.Different refractive factor differences between diopter group were analysised by variance analysis and LSD multiple comparisons.Diopter and refractive factor correlation analysis as well as the ocular axial length(AL)and average corneal refractive power(Kv)were analysised by Pearson correlation analysis.The influence factors of dioptre were analysised by linear multiple factors regression analysis.All the statistical results with P < 0.05 shows it has obvious statistical significance.Results: 1?Refractive factor comparison between different eyes,the axial length of the right eye is longer than left eye and myopia degree of right eye is deeper than the left one which has the statistically significant difference(P < 0.05).2?Refractive factor comparison between different gender groups,the naked vision of boys is better than girls,equivalent spherical mirrors,the ocular axial length and glass body cavity of boys is deeper than girls,corneal refractive power os boy is smaller than girls which has the statistically significant difference(P < 0.05).3?7-12 refractive factor comparison between different ages,along with the age increasing vision and the degree of the equivalent spherical mirrors gradually reduce,while the ocular axial length and anterior chamber depth were increasing gradually along with the age which has the statistically significant difference(P < 0.05).4 ? Different refractive factor comparison between diopter groups,comparison of naked vision in general and between groups have significant difference(P < 0.05).The ocular axial length and glass body cavity depth have obvious difference(P < 0.05)in general,and the comparision has significant dirrerence(P < 0.05)except for normal vision group and low myopia group.Vertical corneal refractive power in general have obvious difference(P < 0.05),and there is obvious difference between face is compared between moderate and high myopia group and the high myopia group compared with medium and low myopia group also had obvious difference(P < 0.05).Average corneal refractive power in general has obvious difference(P < 0.05),and the comparision has significant dirrerence(P < 0.05)except for the low-grade and moderate myopia group.5?Diopter was positively correlated with the naked eye sight(r=0.816,P<0.01),Diopter and eye axis length showed a negative correlation(r = 0.592,P < 0.001).Diopter and corneal refractive power(level corneal refractive power K1,vertical corneal refractive power K2 and average corneal refractive power Kv)showed a negative correlation(r1 = 0.296,P = 0.002;r2 = 0.306,P = 0.001;the rv = 0.204,P = 0.035),showed a negative correlation between diopter and anterior chamber depth(r = 0.237,P = 0.237),showed a negative correlation between diopter and glass body cavity depth(r = 0.362,P < 0.362).6?The multiple linear regression that made by equationdiopter,eye axis length(AL)and average corneal refractive power(Kv)is D=86.129-1.422*AL-1.249*KV.7?Ocular axial length and average corneal refractive power in the correlation between different dioptre group is that in low myopia group,the ocular axial length and average corneal refractive power showed a negative correlation(r = 0.345,P < 0.05),while in moderate myopia group,the ocular axial length and average corneal refractive power showed a negative correlation(r = 0.217,P < 0.05)and in high myopia group,the ocular axial length and average corneal refractive power no correlation(P > 0.05).Conclusion(s):1?Among the normal and myopic children,aged from 7to 12 years old,the myopia degree of the right eye is higher than the left one in the same individual and the myopia degree of the girls are higher than the boys.2?8-9 years old can be considered as an active development of myopia stage of the school-age children.3?The intraocular refractive parameters can adjust each other to delay the myopia progression in normal vision,low myopia and moderate myopia group,while the compensatory mechanism is broken in high myopia group.Among these factors,the most important is the matching relationship between ocular axial length and corneal refractive power.4?The diopter of the schoolchildren aged from 7 to 12 years old can be predicted by the ocular axial length and corneal refractive power from which can deduces the myopia progression and give the children reasonable prevention of myopia.5?To establish the children refractive development electronic files is conducive to the establishment of the new normal refractive parameter database,and it is of great significance for the prevention and control of myopia and individualized diagnosis and treatment of children as well.