低中度近视角膜Q值的测量分析及其临床意义

目的研究中国人低中度近视眼角膜Q值及其分布特点。方法采用Allegretto wave topolyzer角膜地形图仪检测122例（244眼）低中度近视眼角膜地形图，根据Lensfitting显示的不同直径范围内的角膜平均偏心率（8）计算平均Q值（Q=-ε^2），并作统计学分析。结果122例低中度近视眼角膜平均Q值（30°、20°、10°）分别为：右眼-0．30±0．15，左眼为-0．31±0．14；-0．18±0．17，-0．18±0．16；-0．11±0．15，-0．11±0．15。左右眼Q值差异均无显著性（P〉0．05），Q值与K值及屈光度无显著相关性（P〉0．05）。结论低中度近视眼角膜由周边区至中央区Q值增大，即角膜前表面形态为非球面，周边平坦而中央近似球面。

Study of the Q-value of myopic corneas in Chinese people

Objective To study corneal asphericity （Q-value） in Chinese people with mild and medium myopia. Methods One hundred twenty-two people （244 eyes） with mild and medium myopia were examined with an Allegretto Wave Topolyzer, and Q-values were calculated （Q=-ε^2）. Statistical analysis （t-test） was performed. Results The average Q-values of the corneas of Chinese people with mild and medium myopia were Q30=-0.30± 0.15 in the right eye and Q30=-0.31±0.14 in the left eye; Q20= -0.18±0.17 in the fight eye, Q20=-0.18±0.16 in left eye; Q10= -0.11±0.15 in right eye, Q10=-0.11±0.15 in left eye. The difference in the Q-value between the right and left eyes was not significant （P〉0.05）. Conclusion The cornea of Chinese people with mild and medium myopia was found to have a prolate spheroid shape.