Choroidal Thickness Measurements And The Relevant Factors In Myopia Eyes

Objectives:Using EDI-OCT technology of Heidelberg to measure macular region choroidal thickness of high, moderate and low myopia,and compare them.To study variation of choroidal thickness among each group and discuss whether these factors such as gender, age, systolic blood pressure, diastolic blood pressure and intraocular pressure influence the choroidal thickness.Exploring effective ways to treat myopia.Methods:Select 116 eyes of 116 myopia (average age 23.92±3.16 years old).All subjects were excluded from anterior segment and fundus lesions. According to the refractive error to divided into three groups --low myopia group (refraction error less than -3.0D,39 eyes), moderate myopia group (-3.0D< refractive error≤-6.0D,61 eyes) and high myopia group (greater than -6.0D,16 eyes). Using EDI-OCT technology to scan choroidal thickness in the subfoveal and 3000μm of the superior,inferior,nasal, temporal position from the fovea,while collect their age, systolic blood pressure, diastolic blood pressure, height, weight, intraocular pressure. Using multiple independent samples rank sum test and multiple 1 inear regression analysi to analyze the variation in choroidal thickness in each group and the factors of choroidal thickness.Results:1.Each group choroidal thickness (unit:μm)in the subfoveal were as follows:In low myopia group, choroidal thickness in the subfoveal,3000μm of the temporal, nasal, superior and inferior position from the fovea were 287.05±68.31、 283.00±66.8、271.03±70.32、282.87±66.09、195.21±52.43. In moderate myopia group,choroidal thickness 251.13±64.40、252.75±58.29、240.21±68.18、249.66±61.00、 168.43±59.24; In high myopia group choroidal thickness were197.00±35.21、 232.63±45.69、203.50±46.43、221.56±38.36、129.56±30.97.2. In the same group, the choroidal thickness of different position showed:The differences of choroidal thickness in nasal 3000μm and other positions was statistically significant(P<0.05),but the differences of choroidal thickness between superior and inferior 3000μm, temporal and inferior 3000μm, temporal and inferior 3000μm were not statistically significant (P> 0.05).The differences of choroidal thickness between fovea and other position were not statistically significant (P> 0.05). Three groups received the same results.3.In the same position of different groups, the analysis of choroidal thickness showed:Between any two groups, the differences of subfoveal choroidal thickness and nasal 3000μm were statistically significant(P< 0.05);Besides choroidal thickness differences moderate myopia and high myopia group in inferior and nasal 3000μm were not statistically significant(P>0.05), between the rest two group were statistically significant(P<0.05); Between the rest two group were statistically significant(P< 0.05), besides choroidal thickness differences low myopia and moderate myopia group in inferior 3000μm was not statistically significant(P>0.05);4. Using multiple linear regression shows subfoveal choroidal thickness was a negative correlation with age, height, intraocular pressure and spherical equivalent (r=-0.551、-0.223、-0.531、-0.426, P<0.05), while there was no correlation with weight, systolic pressure and diastolic pressure.In addition to temporal, nasal and superior and inferior 3000μm were negative correlation with refractive error (r=-0.368,-0.324、-0.261, P<0.05); Temporal, nasal, superior and inferior 3000μm were negative correlation with age and intraocular pressure (r=-0.540、-0.527、-0.461、-0.447, P<0.05) (r=-0.419、-0.445、-0.522、-0.496, P<0.05);5. Choroidal thickness had no significant differences between the different sexes. Conclusion:1.With the increasing of refractive error of myopia, choroidal thickness in macular region becomes thinner.The choroidal thickness of nasal side is thinnest,and superior is thicker than inferior side.In moderate and high myopia group,the choroidal thickness of temporal side is thickest.From temporal to nasal side,choroidal thickness is thinner.2.choroidal thickness in the subfoveal is negatively correlated with spherical equivalent,age,height and intraocular pressure,and has no relevance with sexes,blood pressure and weight.