Methods: Analysis was done with mydriatic and computer optometry to measure corneal curvature and determine the length of the optic axis.
方法：对近视学生采用散瞳验光和电脑验光及测定患者的角膜曲率和用a超测定眼轴长度而进行分析。
2
To measure central corneal thickness, central corneal diopter and eye axis with ultrasonic A and corneal topography.
利用A超、角膜地形图仪测定上述患者的角膜中央厚度、角膜中央屈光力及眼轴长度。
3
The length of the visual axis was the distance from the corneal vertex to the macular fovea, and it was also measured by A-mode ultrasound in sitting position with different ultrasonic velocity.