近视患者与正常人群的角膜光密度的观察分析

Observation and analysis on corneal densitometry in myopic patients and normal population

目的应用Pentacam三维眼前节分析诊断系统分析不同屈光状态的近视患者与正常人群角膜光密度(CD)的变化规律及与等效球镜度数(SE)、角膜内皮细胞密度(ECD)等参数的相关性。方法选取近视患者和正常人群(NP)共389例(共389只眼),其中NP 89例,低度近视(LM)、中度近视(MM)、高度近视(HM)各100例,采用Pentacam三维眼前节分析仪以角膜顶点为中心,分别测量0~2、2~6、6~10、0~12 mm直径范围的前层(120μm)、中间层、后层(60μm)以及总层的CD。进行CD与SE、ECD等参数的相关性分析。结果NP组与近视组比较,不同直径范围及不同深度CD值差异均有统计学意义(P<0.05)。NP组与LM组比较,前层、中间层及总层的0~2、2~6 mm和后层的0~12 mm差异均有统计学意义(P<0.05)。NP组与MM组比较,不同直径范围及不同深度比较差异均有统计学意义(P<0.05)。NP组与HM组、LM组与HM组比较,除中间层6~10 mm直径外,不同直径范围及不同深度差异均有统计学意义(P<0.05)。LM组与MM组比较,不同直径范围及不同深度差异均有统计学意义(P<0.05)。前层、中间层、后层以及0~10 mm所有直径范围的CD与SE负相关(P<0.05);部分参数与年龄正相关,与角膜直径负相关,但和ECD、中央角膜厚度(CCT)以及角膜曲率无明显相关性。结论随着近视屈光度的增加,角膜光密度值不断增大,即角膜透明度不断下降。因此临床上对近视患者,尤其是高度近视患者的角膜光密度改变需要给予更多的关注。

Objective To observe the changes of corneal densitometry(CD)using Pentacam system analysis between myopic patients with different refractive states and normal population,and to analyze the correlation between CD and refraction spherical equivalent(SE)and corneal endothelial cell density(ECD).Methods 389 patients(389 eyes)including patients with low degree of myopia(LM,n=100),moderate myopia(MM,n=100),high myopia(HM,n=100)and 89 normal patients(NP,89 eyes)were selected in this retrospective study.The corneal densitometry was measured with the Pentacam system analysis.The diameter ranges of 0~2 mm,2~6 mm,6~10 mm,0~12 mm as well as the anterior,middle,posterior and full-thickness corneal density with the apex of the cornea were recorded.Pearson and Spearman correlation were used to analyze the correlation between CD and SE along with ECD.Results Compared with the myopia group,there were statistical differences in CD values between the NP group and the myopia group in different diameter range and depth(P<0.05).Compared with the LM group,the 0~2 mm,2~6 mm of the anterior layer,the middle layer and the total layer and the 0~12 mm of the posterior layer were statistically different in NP group and LM group(P<0.05).Compared with the MM group,there were statistical differences in different diameter range and depth(P<0.05).Compared with the HM group and the NP group,the LM group and the HM group,there were statistical differences in different diameter ranges and depths except for the intermediate layer 6-10mm diameter(P<0.05).There were statistically significant differences between LM group and MM group in different diameter range and depth(P<0.05).There was no significant difference between MM group and HM group in diameter range and depth(P>0.05).Correlation analysis results showed that there was a negative correlation between CD and SE in front layer,middle layer,back layer and all diameter ranges of 0~10 mm(P<0.05).Some parameters were positively correlated with age and negatively correlated with corneal diameter,but none significantly correlated with ECD,CCT and corneal curvature.Conclusion The corneal densitometry value increases,the corneal transparency downwards with the diopter of myopia increased.