578.2nm激光照射对视网膜功能学损伤的研究

Research on Effects of 578.2 nm Laser on Retina Function

目的从功能学的角度研究激光照射后视网膜功能的改变。方法健康灰兔6只共12只眼,按照激光进入眼底的功率密度分为正常组,阈值下组和阈值上组,每组4只兔眼。应用波长578.2 nm、脉宽20～40 ns的脉冲铜蒸汽激光照射兔眼底视乳头下方的后极部,照光时间100 s,眼底光斑直径2 mm。照光后1周用视觉电生理仪采集视网膜电图(electroretinogram,ERG),判定激光对视网膜功能学的损害。结果暗视ERG中,阈值上组和阈值下组的Ab(uv)与正常组相比存在显著差异;暗适应最大电反应中,阈值上组与正常组的Ab(uv)差异显著,阈值下组与正常组的La(ms)差异显著。结论低于损伤阈值剂量的激光照射视网膜出现视网膜功能的改变。

Objective To observe functional changes to rabbits’ retina by applying the 578.2 nm laser pulse with a pulsewidth of 20-40 ns on retinas of rabbit eyes with different power densities（low and high）.Methods Altogether 12 eyes of 6 rabbits were divided into 3 groups（the normal,low dose,high dose groups） and exposed to the 578.2 nm laser with a spot size of 2 mm for 100 s.The retinas were checked with visual electrophysiology instruments a week later,and the judgment whether they were impaired functionally was made.Results As to the scotopia ERG,both the low dose group and high dose group differed from the normal group in Ab（uv）.In regard to biggest electricity reaction of dark adaptation,both the low dose group and high dose group were different from the normal group in La（ms）.Conclusions The electroretinogram showed that the retinas of the rabbits in the low dose group had changed functionally.