个体化切削和超常视力

Customized ablation and supervision

波前像差引导的准分子激光角膜屈光性手术的出现,使个体化切削成为可能,通过矫正人眼生理系统的高阶像差,人们期望获得超常视力及对比敏感度。但由于像差会受到衍射和散射影响,同时还会随时间、泪膜厚度、瞳孔大小以及调节的变化而波动,从而影响得到无像差的视网膜成像。无像差的视网膜成像还要受到视网膜采样以及大脑神经系统识别等因素的影响。因此,个体化切削不一定能产生超常视力。

The idea of supervision has been introduced with the presence of the customized ablation. The concept is related to the ability of obtaining supernormal visual acuity and contrast sensitivity by correction of higher order aberrations in the biological optics of the human eye. However, there are many problems on the way to supervision, such as diffraction, scattering and changing aberrations fluctuating continuously and dynamically over time with the functional state of several of the individual optical components, including thickness of the tear film, size of the pupil, and the degree of lens accommodation. These temporal variations represent major obstacles for achieving aberration-free images. In addition, the central perception of ideal aberration-free images may be hindered by neuronal limitations in retina and brain. Therefore supervision is not waiting around the corner. ·