193nm准分子激光飞点扫描角膜研究

Study on 193 nm Excimer Laser Flying-Spot Scanning Cornea

以近视和散光矫正为例,对193nm准分子激光消融角膜的数学模型进行了推导;研究了193nm准分子激光对角膜的蚀除机理,提出了确定手术中发射的激光脉冲数目以及每个脉冲在角膜上扫描位置的方法,并进行了相应的计算,进而采用间隔N点扫描、随机飞点扫描、连续2点间隔开扫描、连续3点间隔开扫描和分区域扫描等算法,对PMMA板进行了多次扫描实验,并采用裂隙灯对PMMA板表面进行了测量。通过比较,间隔N点扫描和随机飞点扫描算法比较理想,这两种算法已经应用到手术中,并取得了较好的疗效。

Take example for correcting myopia and astigmatism, the mathematical model of corneal ablation with 193 nm excimer laser was deduced. The mechanism of 193 nm excimer laser corneal ablation is studied. The methods to decide the numbers of laser impulse in surgery and every pulse position are put forward and have been done. On the basis of this, a lot of scanning experiments on PMMA have been done by the algorisms of every N points scanning, random flying-spot scanning, two continuous interval points scanning, three continuous interval points scanning and area scanning. The surfaces of PMMA are measured with slit lamp. With comparison, every N points scanning and random flying-spot scanning algorisms are good. Now the two algorisms are used in surgery and the curative effect is nice.