眼轴长度对非病理性近视黄斑区视网膜厚度的影响

目的　使用频域光学相干断层扫描（ｏｐｔｉｃａｌｃｏｈｅｒｅｎｃｅｔｏｍｏｇｒａｐｈｙ，ＯＣＴ）研究眼轴长度对非病理性近视黄斑区视网膜厚度的影响。方法　筛选无眼底改变的近视患者９０例９０眼，男４７例，女４３例，年龄１８～３５岁。入选患者根据屈光度数和眼轴长度分为３组:低、中度近视组（ｌｏｗａｎｄｍｅｄｉｕｍｍｙｏｐｉａｇｒｏｕｐ，ＬＭＭＧ），等效球镜度数为－０．５０～＜－６．００Ｄ且眼轴长度为２４～＜２６ｍｍ，共２９眼；高度近视组（ｈｉｇｈｍｙｏｐｉａｇｒｏｕｐ，ＨＭＧ），等效球镜度数为－６．００～＜－１０．００Ｄ且眼轴长度为２６～＜２８ｍｍ，共３７眼；超高度近视组（ｓｕｐｅｒｈｉｇｈｍｙｏｐｉａｇｒｏｕｐ，ＳＨＭＧ），等效球镜度数≥ －１０．００Ｄ且眼轴长度≥２８ｍｍ，共２４眼。根据黄斑区９分区模式使用ＣｉｒｒｕｓＨＤ－ＯＣＴ检测入选患者黄斑区视网膜厚度和体积。使用单因素方差分析比较３组间黄斑区视网膜厚度测量值的差异。使用线性回归分析黄斑区视网膜厚度测量值与屈光度数和眼轴长度的关系。结果　ＨＭＧ的内环下方黄斑厚度（ｉｎｆｅｒｉｏｒｉｎｎｅｒｍａｃｕｌａｒｔｈｉｃｋｎｅｓｓ，ＩＩＭ）、内环颞侧黄斑厚度（ｔｅｍｐｏｒａｌｉｎｎｅｒｍａｃｕｌａｒｔｈｉｃｋｎｅｓｓ，ＴＩＭ）和外环所有象限的视网膜厚度测量值明显小于ＬＭＭＧ，但黄斑中心区厚度（ｃｅｎｔｒａｌｓｕｂｆｉｅｌｄｔｈｉｃｋｎｅｓｓ，ＣＳＴ）测量值明显大于ＬＭＭＧ（均为Ｐ＜０．０５）。ＳＨＭＧ的ＩＩＭ、ＴＩＭ和外环所有象限的视网膜厚度测量值明显小于ＬＭＭＧ，但ＣＳＴ测量值明显大于ＬＭＭＧ（均为Ｐ＜０．０５）。ＳＨＭＧ外环所有象限的视网膜厚度测量值明显小于ＨＭＧ，但ＣＳＴ测量值明显大于ＨＭＧ（均为Ｐ＜０．０５）。ＣＳＴ测量值与屈光度数呈负相关，与眼轴长度呈正相关。内环平均厚度、ＩＩＭ、ＴＩＭ测量值与屈光度数呈正相关，与眼轴长度呈负相关。外环每一象限的厚度、外环平均厚度、黄斑区平均厚度和黄斑体积测量值与屈光度数均呈正相关，与眼轴长度均呈负相关。结论　随着眼轴长度和屈光度数的增加，非病理性近视眼黄斑中心视网膜厚度增加，内环和外环厚度降低。

Effects of axial length on macular retinal thickness of non-pathological myopia

Objective To investigate the effects of axial length on macular retinal thickness of non-pathological myopia using spectral domain optical coherence tomography ( OCT) . Methods A total of 90 eyes of 90 subjects (47 males and 43 females) who without other eye disorders except for myopia were included in the study. Subjects rang in age was from 18 years t0 35 years. Subjects were divided into three groups according to their refractive error/ axial length : low and medium myopia group LMMG , spherical equivalent ( SE) between - 0. 50 D and - 6. 00 D and axial length 24 - 26 mm . n = 29 ] , high myopia group ( HMG, SE between - 6. 00 D and - 10. 00 D and axial length 26 - 28 mm,n = 37) and super high myopia group ( SHMG, SE； - 10. 00 D and axial length≥ 28 mm.n = 34). Cirrus HD-OCT was used to evaluate macular retinal thickness and macular volume. The differences among experimental groups were analyzed by one-factor analysis of variance. Associations between macular thickness and refractive error/axial length were analyzed by Pearson correlation analysis. Results The inferior rnner macular thickness ( IIM ) , temporal inner macular thickness ( TIM ) and all quadrants of outer ring in HMG group were sigruficantly less than those in LMMG group. However,the central subfield thickness ( CST) in HMG group was significantly greater than that in LMMG group ( all P < 0. 05 ) . IIM .TIM and all quadrants of outer ring in SHMG group were significantly less than those in LMMG group. However ,the CST of SHMG group was sigruficantly greater than that in LMMG group ( all P < 0. 05 ) . Retinal thickness in all quadrants of outer ring in SHMG group was sigruficantly less than those in HMG group. However.the CST in SHMG group was significantly greater than that of HMG ( all P < 0. 05 ) . The CST had negative correlations with refractive error and positive correlations with axial length. The IIM , TIM , all the quadrants of outer ring , total average macular thickness and macular volume featured positive correlations with refractive error , and negative correlations with axial length. Conclusion With an rncrease in myopia degree/axial length, the central subfield thickness increases , and the inner/outer macular thickness decreases.