江西近视手术人群角膜前表面非球性参数调查分析

目的 调查江西近视激光手术人群角膜前表面非球性参数(Q值)的分布特征,并分析Q值与其他参数如屈光度、角膜平均曲率、角膜散光、像差、年龄等凶素的关系.方法 应用Orhscan- Ⅱ角膜 地形图仪(Bausch & Lomb)K＆Q计算软件获得411例近视患者822只眼角膜6mm分析区域的Q值和K值,使用Zywave波前像差仪获取完全的像差分布图像.按性别不同分为男性组(188例376只眼)和女性组(223例446只眼).按照近视程度不同分为轻、中、高度三组.按年龄分为Ⅰ组(17～25岁)、Ⅱ组(26～34岁)、Ⅲ组(35～44岁)三组.并对性别间、不同程度近视、不同年龄组间Q值的差别,总体Q值的分布及与其他参数如屈光度、角膜平均曲率、角膜散光、像差、年龄等因素的相关性进行统计学分析.结果 411例822只近视眼角膜Q值呈正态分布,总体Q值平均为-0.148±0.120,男性为-0.130±0.128,女性为-0.163±0.110,男女间差异有统计学意义(t=4.069,P<0.01).不同程度近视组间角膜Q值差异无统计学意义(F=1.434,r=0.239,P>0.05),Q值与近视屈光不正度数间无明显相关;不同年龄组间Q值的差异有统计学意义(F=4.567,P<0.05),26～ 34岁和35～44岁组间角膜Q值差异有统计学意义(P<0.01);Q值与平均角膜曲率、角膜散光、高阶像差(RMSh)和水平彗差(C8)间均有统计学的相关性,尤其与球差(C12)间存在显著负相关,但与其他参数如总体像差(RMSg)、垂直彗差(C7)、角膜直径、角膜厚度、眼压、年龄之间无明显统计学相关性.结论 适宜激光手术的江西近视人群Q值呈正态分布,大部分人群的角膜曲率由中央到周边逐渐变平.角膜Q值与近视程度无关,个体间变异较大.Q值与平均角膜曲率、角膜散光、高阶像差(RMSh)和水平彗差(C8)相关,Q值和球差之间存在密切相关.性别间角膜Q值有统计学差异性,不同年龄组间的角膜Q值有统计学差异性.

Investigation and analysis of Q value of corneal anterior surface in jiangxi myopia population for laser refractive surgery

Objective To assess the distribution features of Q-value of corneal anterior surface in Jiangxi myopia population for laser refractive surgery and to investigate the relationship between Q-value and other related parameters, such as spherical equivalent (SE), corneal curvature, cornea astigmatism, wavefront data and age. Methods The K&Q calculator of Orbsean- Ⅱ anterior segment system was used to obtain the Q-value of 6 mm optical zone in 411 cases (822 eyes) .There were 188 male subjects (376 eyes) and 223 female subjects (446 eyes). Accnrding to SE, subjects were divided into three groups including low myopia, moderate myopia and high myopia. According to different age, subjects were divided into three groups including group Ⅰ (age from 17 to 25), group Ⅱ (age from 26 to 34) and group Ⅲ (age from 35 to 44). Statistical analysis was used to comprehend the distribution characters of Q-value and its relations with SE, corneal curvature, cornea astigmatism, wavefront data and age. Results The Q-value of 822 eyes (411 cases) distributed as positive normal distribution, the average of Q- value was -0.148± 0.120 (range from -0.73 to 0.56) and -0.130± 0.128for male subjects and -0.163± 0.110 for female ones with statistically significant difference in Q-value in different genders (t=4.069, P <0.01). A significant difference was observed in Q-value among 17-25 years, 26-34 years and 35-44 years groups (F =4.567, P <0.05) as well as between 26-34 years group and 35-44 years group (P =0.004). However, there was no significant difference found between different myopic groups (F =1.434, P >0.05). The Q-value shown significantly negative relationship with C12, the Q-value show poor relationship with cornea curvature, cornea astigmatism, RMSh and C8. But the Q-value was not related with SE, RMSg, C7, cornea thickness, ocular pressure and age. Conclusions In Jiangxi myopia population for refractive surgery corneal curvature of majority population become flatter from center to periphery (Q<0), minority become steeper from center to periphery (Q>0). The Q-value of corneal anterior surface is independent from myopic SE. The Q-value show poor relationship with cornea curvature, cornea astigmatism, RMSh and C8, C12 is the most important related factor of Q-value. The Q-value is significantly greater in males than in females. A significant difference is observed in Q-value between 26-34 years and 35-44 years group.