角膜曲率区域分布及随年龄变化趋势分析

Research of Corneal Power Distribution and Age-Related Change in Cornea

目的:探讨以瞳孔为中心2、4、6 mm直径区域的角膜曲率分布特点及随年龄的变化趋势。方法:回顾性系列病例研究。采用随机抽样方法收集2018年4月至2019年10月就诊于潍坊眼科医院并行Pentacam检查的门诊患者138例(254眼),其中20~39岁51例(102眼)作为A组;40~59岁41例(73眼)作为B组;60岁及以上46例(79眼)作为C组。分别收集以瞳孔为中心2、4、6 mm直径区域的模拟角膜曲率(Simk)和全角膜屈光力(TCRP)数值。采用方差分析比较3组间Simk和TCRP差异,并使用Bland-Altman散点图描述Simk与TCRP之间的一致性。角膜曲率随年龄的变化趋势采用回归分析,不同直径区域的Simk与TCRP采用配对样本t检验进行比较。结果:以瞳孔为中心2、4 mm区域Simk与对应区域TCRP差异有统计学意义(t=6.30,P=0.002;t=4.44,P=0.001);而以瞳孔为中心6 mm区域的Simk和TCRP差异无统计学意义(P>0.05)。在以瞳孔为中心2 mm区域下,3组间Simk、TCRP总体差异均有统计学意义(F=4.66,P=0.010;F=3.87,P=0.022),其中A组与B组、C组Simk和TCRP差异均有统计学意义(均P<0.05),余组间差异无统计学意义(P>0.05);在以瞳孔为中心4 mm区域下,3组间Simk、TCRP总体差异均有统计学意义(F=6.85,P=0.001;F=6.07,P=0.003),其中A组与B组、C组Simk和TCRP差异均有统计学意义(均P<0.05),余组间差异无统计学意义(P>0.05);在以瞳孔为中心6 mm区域下,3组间的Simk、TCRP总体差异均有统计学意义(F=9.91,P<0.001;F=10.15,P<0.001),其中A组与B组、C组Simk和TCRP差异均有统计学意义(均P<0.001),余差异无统计学意义(P>0.05)。结论:以瞳孔为中心不同直径区域的模拟角膜曲率与全角膜屈光力的变化及随年龄变化趋势应在人工晶状体计算及屈光手术中引起重视。Simk与TCRP数值均随年龄增加逐渐变陡峭,40岁之后趋于稳定。

Objective:To investigate the distribution characteristics of corneal power of 2 mm,4 mm and 6 mm diameter zones centered on the pupil and age-related change in cornea.Methods:In this retrospective serial case study,a total of 254 eyes were included by randomly,which were divided into three groups by age,including 20-39 age group(Group A,102 eyes),40-59 age group(Group B,73 eyes)and≥60 age group(Group C,79 eyes).Simulated keratometry(Simk),total corneal refractive power(TCRP)were evaluated.Analysis of Variance was used for comparing the difference between Simk and TCRP.Evaluating uniformity of Simk and TCRP was based on Bland-Altman plot.Regression analysis was used for the age-related trend of Simk and TCRP.Paired-samples t test was used to compare the difference between Simk and TCRP in 2,4 and 6 mm.Results:The Simk and TCRP of 2,4 mm diameter zones centered on the pupil were significant differences between them(t=6.30,P=0.002;t=4.44,P=0.001);However,The Simk and TCRP of 6 mm diameter zones centered on the pupil were no statistically significant differences between them(P>0.05).In 2 mm diameter zones centered on the pupil,there were statistically significant differences between three groups(F=4.66,P=0.010;F=3.87,P=0.022),Among them,group A was significant different from B and C(P<0.05).In 4 mm diameter zones centered on the pupil,there were statistically significant differences between three groups(F=6.85,P=0.001;F=6.07,P=0.003).Among them,group A was significant different from B and C(P<0.05).In 6 mm diameter zones centered on the pupil,there were statistically significant differences between three groups(F=9.91,P<0.001;F=10.15,P<0.001),both Simk and TCRP of A group in all corneal diameter zones showed statistically significant differences with B,C group respectively(P<0.001).Conclusion:Simk and TCRP centered on pupil and the age-related change in corneal should be taken seriously in corneal refractive surgery and cataract surgery.Simk and TCRP shows steeper with aging,which may tend to be stable after 40 years old.